How to use TM1637 chip for LED Display?

[Balachandar]

Hi All,

For the past 10 days, I have been trying to make the TM1637 work with PBP 2.60C but till now I have not been successful. It's a real low cost module. The price of the TM1637 4-digit 7-segment 0.36" display module is about $ 0.60 in Ali Express. There is a 0.56" version and that costs about $ 1.25.
The module works fine with Arduino, but all the important instructions to interface with TM1637 are in the library file (TM1637Display.h). After spending some time with the library file, I decided to study the datasheet of the chip and write the required code in PBP. The protocol followed by the chip is very similar to I2C with a few differences. Like I2C, it's a two-wire interface but you can have only one slave on the bus and hence there is no slave address. Secondly, while transmitting a byte, the LS bit is sent first.

The code I wrote for PIC 12F1840 is shown below and it is extremely simple. It should make the number '2' appear on the leftmost digit of the display. When I tested the code, the diagnostic LED blinked, but after that nothing happened. I used Saleae Logic Analyzer to check whether the Clock & Data pulses and Ack were all OK. After some tweaking, I managed to get everything correct (Screenshot file attached). The only issue is, the display shows nothing! Since I know that the module is working fine with Arduino, it's my code in PBP that needs to be looked into.

I would highly appreciate any helpful hint, suggestion or sample code.

- Bala


'---------------------------------------------------------------------------
' This code is for using TM1637 with Four-digit 7-segment LED Display
' with PIC12F1840. Osc is set at 16MHz.
'---------------------------------------------------------------------------
'---------------------------------------------------------------------------
'12F1840 Pinout:
' -------------------------------------------------------
' VDD VSS
' PortA.5 = Not_used PortA.0 = LED
' PortA.4 = Not_used PortA.1 = DIO
' PortA.3 = Not_used PortA.2 = CLK
' -------------------------------------------------------

'@ __CONFIG _CONFIG1, _FOSC_INTOSC & _WDTE_ON & _PWRTE_ON & _MCLRE_OFF & _BOREN_OFF
'@ __CONFIG _CONFIG2, _PLLEN_OFF & _BORV_LO & _LVP_OFF

ASM
ifndef __12F1840
error "12F1840 not selected"
endif
ENDASM

OSCCON = %01111000 '16MHz HF, software PLL disabled
DEFINE OSC 16

'Port direction
TRISA = %001000 'A.3 is input, rest are outputs.

CM1CON0 = 0 'Disable comparator
ANSELA = 0 'Disable A to D

'List of Aliases
LED var PortA.0
DIO var PortA.1
CLK var PortA.2
TrisDIO VAR TrisA.1

'List of variables
Cnt var byte
ByteToSend var byte 'Command or Data byte to be sent

DispCmd var byte
dispcmd = 64 'Command byte for displaying characters starting with the leftmost digit (0b01000000)

Brt8Cmd var byte
brt8cmd = 143 'Command byte for display on with maximum brightness (0b10001111)

Dig1Addr var byte
dig1addr = 192 'Address of digit 1 (left most) (0b11000000)

DispNum var byte
dispnum = 146 ' "2" (Common anode) (10010010)

'Diagnostic routine
DiagRoutine:
for cnt = 1 to 4 'Blink LED 4 times.
led = 1 : pause 100
led = 0 : pause 100
next cnt

goto start

'Subroutines
StartCondition:
clk = 0
dio = 1
clk = 1
pauseus 50
dio = 0 'DIO goes low when CLK is high.
pauseus 50
return

SendTheByte:
clk = 0
for cnt = 7 to 0 step -1 'Send 8 bits of data, starting with the LSB.
dio = bytetosend.0(cnt)
pauseus 50
clk = 1
pauseus 50
clk = 0
Next cnt
'dio = 1
Trisdio = 1 ' Set Data pin direction to input to receive ACK.
pauseus 50
clk = 1
pauseus 50
clk = 0
Trisdio = 0 ' Set Data pin direction back to output.
return

StopCondition:
clk = 0
dio = 0
clk = 1
pauseus 50
dio = 1 'DIO goes high when CLK is high.
pauseus 50
return

START:

bytetosend = brt8cmd 'Brt8Cmd (10001111) (143) = Command for Display On with Maximum Brightness
gosub startcondition
gosub sendthebyte
gosub stopcondition

bytetosend = dispcmd 'DispCmd (01000000) (64) = Command byte with auto increment sent before sending the digit data
gosub startcondition
gosub sendthebyte
gosub stopcondition

bytetosend = dig1addr 'Dig1Addr (11000000) (192) = Address of digit 1 (leftmost digit)
gosub startcondition
gosub sendthebyte

bytetosend = dispnum ' Number "2" (10010010) (146) (Common anode)
gosub sendthebyte

gosub stopcondition


END

[mpgmike]

Don't know much about your TM1637, but the one thing that jumped out for me was:



for cnt = 7 to 0 step -1 'Send 8 bits of data, starting with the LSB.
dio = bytetosend.0(cnt)

I think your FOR/NEXT would be shifting MSB first (bit7, bit6, bit5...)

If you're getting bits banging out, maybe I'm wrong, but try:



for cnt = 0 to 7
dio = bytetosend.(cnt)


Haven't tried that code, not even in simulation.

[richard]

Mike is correct
try this , it works on a 12f1822
note leds 2,3 and 4 show random crap since nothing is written to them
and not using lat regs is asking for trouble

nearly forgot dispnum = 146 ' "2" (Common anode) (10010010)
not on my display

dispnum = $5b ' "2" (Common anode) (01011101)




OSCCON = %01111000 '16MHz HF, software PLL disabled
DEFINE OSC 16

'Port direction
TRISA = %001000 'A.3 is input, rest are outputs.

CM1CON0 = 0 'Disable comparator
ANSELA = 0 'Disable A to D

'List of Aliases
LED var PortA.0
DIO var LATA.1
CLK var LATA.2
TrisDIO VAR TrisA.1

'List of variables
Cnt var byte
ByteToSend var byte 'Command or Data byte to be sent

DispCmd var byte
dispcmd = 64 'Command byte for displaying characters starting with the leftmost digit (0b01000000)

Brt8Cmd var byte
brt8cmd = 143 'Command byte for display on with maximum brightness (0b10001111)

Dig1Addr var byte
dig1addr = 192 'Address of digit 1 (left most) (0b11000000)

DispNum var byte
dispnum = $5B' "2" (Common anode) (10010010)

'Diagnostic routine
DiagRoutine:
CLK=1
for cnt = 1 to 4 'Blink LED 4 times.
led = 1 : pause 100
led = 0 : pause 100
next cnt

goto start

'Subroutines
StartCondition:
clk = 0
dio = 1
clk = 1
pauseus 50
dio = 0 'DIO goes low when CLK is high.
pauseus 50
return

SendTheByte:
clk = 0
for cnt = 0 to 7 'Send 8 bits of data, starting with the LSB.
dio = bytetosend.0(cnt)
pauseus 50
clk = 1
pauseus 50
clk = 0
Next cnt
'dio = 1
Trisdio = 1 ' Set Data pin direction to input to receive ACK.
pauseus 50
clk = 1
pauseus 50
clk = 0
Trisdio = 0 ' Set Data pin direction back to output.
return

StopCondition:
clk = 0
dio = 0
clk = 1
pauseus 50
dio = 1 'DIO goes high when CLK is high.
pauseus 50
return

START:



bytetosend = dispcmd 'DispCmd (01000000) (64) = Command byte with auto increment sent before sending the digit data
gosub startcondition
gosub sendthebyte
gosub stopcondition

bytetosend = dig1addr 'Dig1Addr (11000000) (192) = Address of digit 1 (leftmost digit)
gosub startcondition
gosub sendthebyte

bytetosend = dispnum ' Number "2" (10010010) (146) (Common anode)
gosub sendthebyte

gosub stopcondition
bytetosend = brt8cmd 'Brt8Cmd (10001111) (143) = Command for Display On with Maximum Brightness
gosub startcondition
gosub sendthebyte
gosub stopcondition

END

[Balachandar]

Mpgmike & Richard, thanks a lot for your comments and suggestions.

I first tried 'FOR Cnt = 0 to 7'. Since that didn't work, I changed the code to ''FOR Cnt = 7 to 0 STEP -1' to see whether that would make a difference; still the display wouldn't turn on. I agree; if the LSB is to be sent first, it should be 'FOR Cnt = 0 to 7'.

Richard, you are saying, not using LAT registers is asking for trouble. But since the bits for PortA 0, 1 & 2 are cleared in the TRIS register, they have been clearly defined as outputs right in the beginning of the code. Would it make any difference, whether you call it PortA.1 or LATA.1? Are you not referring to the Output in either case? Secondly, referring to the output as LAT results in compilation errors in PBP 2.60C for older PICs like 12F683.

I corrected the code as per the suggestions given, but the display does not turn on. I also tried the same code with a 12F683 at 8MHz IntOsc. Again, there is no good news to report.

In the absence of any working PBP code for TM1637, my only option seems to be that I need to do an in-depth study of the Arduino library files and get a clear understanding to be able to write a working PBP code.

[richard]

In the absence of any working PBP code for TM1637, my only option seems to be that I need to do an in-depth study of the Arduino library files and get a clear understanding to be able to write a working PBP code.

the corrected version of your code I posted works for me


the code I posted here works
http://www.picbasic.co.uk/forum/showthread.php?t=23417


sheldons code posted here works

http://www.picbasic.co.uk/forum/showthread.php?t=23974
(http://www.picbasic.co.uk/forum/showthread.php?t=23974)

your code is a bit glitchy and about 30 times too slow but it can work

see difference in these pics

[richard]

Richard, you are saying, not using LAT registers is asking for trouble. But since the bits for PortA 0, 1 & 2 are cleared in the TRIS register, they have been clearly defined as outputs right in the beginning of the code. Would it make any difference, whether you call it PortA.1 or LATA.1? Are you not referring to the Output in either case? Secondly, referring to the output as LAT results in compilation errors in PBP 2.60C for older PICs like 12F683.

its all about rmw errors , 12f683 has no lat regs

https://www.microchip.com/webinars.microchip.com/WebinarDetails.aspx?dDocName=en556253

[Balachandar]

Thank you Richard, for the clarity you provided on LAT registers.
Couple of days back, I downloaded PBP 3.1.1 with the idea of trying it out and to compile codes written for Ver 3 and above.
I used your demo code (TM1637-DEMO.pbp.txt), made suitable changes for PIC 18F2620 at 32MHz, configured PortB pins 0, 6 & 7 for LED, DIO & CLK respectively and made the required changes in the ASM section for the same. But on compiling, many errors are reported like "Illegal opcode (FSR0)" and "Found label after column 1".
Attached is my code and the screenshot showing the compilation errors. I am clueless as to where the issue is and your help is appreciated.



define OSC 32 ' (8 x 4 = 32)

; --- *** Oscillator *** ---------------------------------------------------

OSCCON = %01110000 'Int Osc: 8MHz
'(Bits 4, 5 & 6 determine the internal clock speed).
' 111 = 8MHz 110 = 4MHz
'OSCTUNE = %10000000 'PLL is disabled.
OSCTUNE = %11000000 'PLL is enabled.

TRISA = 0
TRISB = 0
TRISC = 0

CMCON = 7 'Disable the comparators of PortA
ADCON0 = 0 'Disable ADC
ADCON1 = 15 'All pins of Port A are digital I/O
' ANSELb = 0
' ANSELA = 0
' ANSELC = 0

LED VAR PORTB.0 ' Assign name "LED" to

USERCOMMAND "DISPLED" ; BUFFER{,COLON }
USERCOMMAND "STRLEN" ; BUFFER
USERCOMMAND "RJUSTBUFF" ; BUFFER

TM_BIT VAR BYTE BANK0
TM_DAT VAR BYTE BANK0
TM_NAK VAR BYTE BANK0 ;set to $80 if tx error occured
TM_DIG VAR BYTE BANK0
TM_BRIGHT VAR BYTE BANK0 ;display pwm level 0 to 7
TM_COLON VAR BYTE BANK0 ;display colon 0/1
TM_TMP VAR BYTE[2] BANK0
str_len VAR BYTE BANK0

CMD_AUTO_ADDR CON $40
START_ADDR CON $c0
NUM_DIGITS CON 4 ;number of 7seg leds
COLON_FLAG CON $80
DISPLAY_ON CON $88
;tm1637 DIO AND CLK NEED TO BE ON SAME PORT
@TM_OUT_PORT = LATB ;TM_DIO OUT
@TM_IN_PORT = PORTB ;TM_DIO IN
@TM_CLK = 6 ;PIN
@TM_DIO = 7 ;PIN
@TM_TRIS = TRISB

BLINK VAR BYTE
LEDBUFF VAR BYTE[NUM_DIGITS +1]
COUNTER VAR byte

GOTO OVERASM

ASM
DISPLED?B macro BUFFER
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
L?CALL _TM_DISP4
endm
DISPLED?BC macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
MOVE?CB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
DISPLED?BB macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
MOVE?BB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm

STRLEN?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
L?CALL STRlen
endm
RJUSTBUFF?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
MOVE?CB low BUF, _TM_TMP ;load low byte
MOVE?CB HIGH BUF, _TM_TMP+1 ;load low byte
L?CALL STRlen
L?CALL _strpad
endm


STRlen ;get buffer usage size
CLRF _str_len
str_tok_chr
MOVIW FSR0 ++ ; Get character
btfsC STATUS,Z
goto exit_str_null ; EXIT ON Null char
INCF _str_len,F ; not null so increment index
goto str_tok_chr
exit_str_null
return

_strpad ;right justify by padding with spaces " "
BANKSEL _str_len
movlw _NUM_DIGITS+1 ;buffer size
subwf _str_len,f ;tx string size
comf _str_len,f ;the difference is number of spaces to SHIFT in
btfsc STATUS, Z
goto expd ;if zero difference then exit
nxpd
movf _TM_TMP,w ;addr of buffer l
MOVWF FSR0
movf _TM_TMP+1,w ;addr of buffer h
MOVWF FSR0+1
movlw _NUM_DIGITS
addwf FSR0,f
movf FSR0,w
movwf FSR1
movf FSR0+1,w
movwf FSR1+1
DECF FSR0,F ;offset pointer 0
BANKSEL _TM_BIT
movlw _NUM_DIGITS
movwf _TM_BIT
nxby ;buffer shift right x 1
MOVIW FSR0 --
MOVWI FSR1 --
DECFSZ _TM_BIT,F
GOTO nxby
movlw 0x20
MOVWI FSR1 -- ;poke a space in buff[0]
BANKSEL _str_len
DECFSZ _str_len,F ;need another one ?
goto nxpd
expd ;nah!
return


SEG_val
CHK?RP _TM_TMP
MOVWF _TM_TMP
SUBLW 0x21
btfsc STATUS, C
retlw 0 ;" "
MOVF _TM_TMP,W
SUBLW 0x2f
btfsc STATUS, C
retlw 64 ;"-"
MOVF _TM_TMP,W
MOVLW 0X40
SUBWF _TM_TMP,W
btfsC STATUS, C
GOTO TM_ALPHA
MOVF _TM_TMP,W
ANDLW 0X0F
GOTO TM_LU
TM_ALPHA
ANDLW 0xdf ;ucase
SUBLW 6
btfsS STATUS, C
retlw 0 ;ERROR
MOVLW 0X37
SUBWF _TM_TMP,W
ANDLW 0xdf ;ucase
TM_LU
BRW
retlw 0X3F ;0
retlw 6
retlw 0X5B
retlw 0X4F
retlw 0X66
retlw 0X6D
retlw 0X7D
retlw 7
retlw 0X7F
retlw 0X67 ;9
retlw 0X77 ;A
retlw 0X7C ;b
retlw 0X39 ;C
retlw 0X5E ;d
retlw 0X79 ;E
retlw 0X71 ;F

TM_START
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
BSF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_CLK
NOP
RETURN

TM_STOP
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
BCF TM_OUT_PORT,TM_DIO
NOP
BSF TM_OUT_PORT,TM_CLK
NOP
BSF TM_OUT_PORT,TM_DIO
NOP
RETURN

TM_WRITE
MOVLW 8
CHK?RP _TM_BIT
MOVWF _TM_BIT
NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP _TM_DAT
BTFSS _TM_DAT,0
GOTO TM_0
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_DIO
GOTO TM_NB
TM_0
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_DIO
TM_NB
CHK?RP _TM_DAT
RRF _TM_DAT,F
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
CHK?RP _TM_BIT
DECFSZ _TM_BIT,F
GOTO NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BSF TM_TRIS,TM_DIO
CHK?RP TM_IN_PORT
BTFSC TM_IN_PORT,TM_DIO
BSF _TM_NAK,7
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
NOP
NOP
NOP
NOP
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
RST?RP
RETURN
_TM_INIT
CHK?RP _TM_COLON
CLRF _TM_COLON
CLRF _TM_BRIGHT
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
BCF TM_TRIS ,TM_CLK
RST?RP
RETURN

_TM_DISP4
MOVLW _CMD_AUTO_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CLRF _TM_NAK
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
MOVLW _NUM_DIGITS
CHK?RP _TM_DIG
MOVWF _TM_DIG
MOVLW _START_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
NXDIG
MOVIW FSR0 ++
CALL SEG_val
CHK?RP _TM_DAT
IORWF _TM_COLON ,W
movwf _TM_DAT
CALL TM_WRITE
CHK?RP _TM_DIG
DECFSZ _TM_DIG,F
GOTO NXDIG
CALL TM_STOP
CHK?RP _TM_BRIGHT
MOVF _TM_BRIGHT ,W
ANDLW 7
IORLW _DISPLAY_ON
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
RST?RP
RETURN
ENDASM

OVERASM:

CALL TM_INIT


ALOOP:
TOGGLE LED
TM_BRIGHT=TM_BRIGHT-1
if TM_BRIGHT>7 then TM_BRIGHT=7
ARRAYWRITE LEDBUFF ,["b- ",#TM_BRIGHT,0]
DISPLED LEDBUFF,0
PAUSE 500
FOR COUNTER=0 TO 255
ARRAYWRITE LEDBUFF ,[hex COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,BLINK
PAUSE 50
NEXT
FOR COUNTER=0 TO 255
IF !(COUNTER//20) THEN BLINK = TM_COLON ^ $80
ARRAYWRITE LEDBUFF ,[sdec COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,BLINK
PAUSE 50
NEXT
goto ALOOP

Screenshot showing errors:
8777

[richard]

MY code is for a pic16 with enhanced core it needs some changes to operate on older chips and/or pic18

moviw fsrx ++ can be replaced with
MOVF INDFx,W
INCF FSRx

brw becomes
addwf PCL, F ; as long as you don't overflow pcl

pic 18 has no rrf code
repl with rrcf



PIC 18F2620 version , not tested did compile ok



#CONFIG
CONFIG OSC=INTIO67, FCMEN=OFF, IESO=OFF, PWRT=OFF, BOREN=SBORDIS, BORV=3
CONFIG WDT=ON, WDTPS=512, CCP2MX=PORTC, PBADEN=OFF, LPT1OSC=OFF, MCLRE=ON
CONFIG STVREN=ON, LVP=OFF, XINST=OFF, DEBUG=OFF, CP0=OFF, CP1=OFF, CP2=OFF
CONFIG CP3=OFF, CPB=OFF, CPD=OFF, WRT0=OFF, WRT1=OFF, WRT2=OFF, WRT3=OFF
CONFIG WRTC=OFF, WRTB=OFF, WRTD=OFF, EBTR0=OFF, EBTR1=OFF, EBTR2=OFF
CONFIG EBTR3=OFF, EBTRB=OFF
#ENDCONFIG


define OSC 32 ' (8 x 4 = 32)
; --- *** Oscillator *** ---------------------------------------------------
OSCCON = %01110000 'Int Osc: 8MHz
'(Bits 4, 5 & 6 determine the internal clock speed).
' 111 = 8MHz 110 = 4MHz
'OSCTUNE = %11000000 'PLL is disabled. what??????????????
OSCTUNE.6 = 1 'PLL is enabled.
TRISA = 0
TRISB = 0
TRISC = 0

'CMCON = 7 'Disable the comparators of PortA
'ADCON0 = 0 'Disable ADC
ADCON1 = 15 'All pins of Port A are digital I/O
' ANSELb = 0
' ANSELA = 0
' ANSELC = 0
LED VAR PORTB.0 ' Assign name "LED" to

USERCOMMAND "DISPLED" ; BUFFER{,COLON }
USERCOMMAND "STRLEN" ; BUFFER
USERCOMMAND "RJUSTBUFF" ; BUFFER

TM_BIT VAR BYTE BANK0
TM_DAT VAR BYTE BANK0
TM_NAK VAR BYTE BANK0 ;set to $80 if tx error occured
TM_DIG VAR BYTE BANK0
TM_BRIGHT VAR BYTE BANK0 ;display pwm level 0 to 7
TM_COLON VAR BYTE BANK0 ;display colon 0/1
TM_TMP VAR BYTE[2] BANK0
str_len VAR BYTE BANK0

CMD_AUTO_ADDR CON $40
START_ADDR CON $c0
NUM_DIGITS CON 4 ;number of 7seg leds
COLON_FLAG CON $80
DISPLAY_ON CON $88
;tm1637 DIO AND CLK NEED TO BE ON SAME PORT
@TM_OUT_PORT = LATB ;TM_DIO OUT
@TM_IN_PORT = PORTB ;TM_DIO IN
@TM_CLK = 6 ;PIN
@TM_DIO = 7 ;PIN
@TM_TRIS = TRISB

BLINK VAR BYTE
LEDBUFF VAR BYTE[NUM_DIGITS +1]
COUNTER VAR byte

GOTO OVERASM

ASM
DISPLED?B macro BUFFER
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
L?CALL _TM_DISP4
endm
DISPLED?BC macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
MOVE?CB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
DISPLED?BB macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
MOVE?BB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
STRLEN?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
L?CALL STRlen
endm
RJUSTBUFF?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
MOVE?CB low BUF, _TM_TMP ;load low byte
MOVE?CB HIGH BUF, _TM_TMP+1 ;load low byte
L?CALL STRlen
L?CALL _strpad
endm


STRlen ;get buffer usage size
CLRF _str_len
str_tok_chr
;MOVIW FSR0 ++ ; Get character
MOVF INDF0,W
INCF FSR0
btfsC STATUS,Z
goto exit_str_null ; EXIT ON Null char
INCF _str_len,F ; not null so increment index
goto str_tok_chr
exit_str_null
return
_strpad ;right justify by padding with spaces " "
BANKSEL _str_len
movlw _NUM_DIGITS+1 ;buffer size
subwf _str_len,f ;tx string size
comf _str_len,f ;the difference is number of spaces to SHIFT in
btfsc STATUS, Z
goto expd ;if zero difference then exit
nxpd
movf _TM_TMP,w ;addr of buffer l
MOVWF FSR0
movf _TM_TMP+1,w ;addr of buffer h
MOVWF FSR0+1
movlw _NUM_DIGITS
addwf FSR0,f
movf FSR0,w
movwf FSR1
movf FSR0+1,w
movwf FSR1+1
DECF FSR0,F ;offset pointer 0
BANKSEL _TM_BIT
movlw _NUM_DIGITS
movwf _TM_BIT
nxby ;buffer shift right x 1
;MOVIW FSR0 --
MOVF INDF0,W
DECF FSR0
;MOVWI FSR1 --
MOVF INDF1,W
DECF FSR1
DECFSZ _TM_BIT,F
GOTO nxby
movlw 0x20
;MOVWI FSR1 -- ;poke a space in buff[0]
MOVF INDF1,W
DECF FSR1
BANKSEL _str_len
DECFSZ _str_len,F ;need another one ?
goto nxpd
expd ;nah!
return

SEG_val
CHK?RP _TM_TMP
MOVWF _TM_TMP
SUBLW 0x21
btfsc STATUS, C
retlw 0 ;" "
MOVF _TM_TMP,W
SUBLW 0x2f
btfsc STATUS, C
retlw 64 ;"-"
MOVF _TM_TMP,W
MOVLW 0X40
SUBWF _TM_TMP,W
btfsC STATUS, C
GOTO TM_ALPHA
MOVF _TM_TMP,W
ANDLW 0X0F
GOTO TM_LU
TM_ALPHA
ANDLW 0xdf ;ucase
SUBLW 6
btfsS STATUS, C
retlw 0 ;ERROR
MOVLW 0X37
SUBWF _TM_TMP,W
ANDLW 0xdf ;ucase
TM_LU
addwf PCL, F
retlw 0X3F ;0
retlw 6
retlw 0X5B
retlw 0X4F
retlw 0X66
retlw 0X6D
retlw 0X7D
retlw 7
retlw 0X7F
retlw 0X67 ;9
retlw 0X77 ;A
retlw 0X7C ;b
retlw 0X39 ;C
retlw 0X5E ;d
retlw 0X79 ;E
retlw 0X71 ;F

TM_START
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
BSF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_CLK
NOP
RETURN

TM_STOP
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
BCF TM_OUT_PORT,TM_DIO
NOP
BSF TM_OUT_PORT,TM_CLK
NOP
BSF TM_OUT_PORT,TM_DIO
NOP
RETURN

TM_WRITE
MOVLW 8
CHK?RP _TM_BIT
MOVWF _TM_BIT
NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP _TM_DAT
BTFSS _TM_DAT,0
GOTO TM_0
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_DIO
GOTO TM_NB
TM_0
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_DIO
TM_NB
CHK?RP _TM_DAT
RRCF _TM_DAT,F
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
CHK?RP _TM_BIT
DECFSZ _TM_BIT,F
GOTO NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BSF TM_TRIS,TM_DIO
CHK?RP TM_IN_PORT
BTFSC TM_IN_PORT,TM_DIO
BSF _TM_NAK,7
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
NOP
NOP
NOP
NOP
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
RST?RP
RETURN
_TM_INIT
CHK?RP _TM_COLON
CLRF _TM_COLON
CLRF _TM_BRIGHT
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
BCF TM_TRIS ,TM_CLK
RST?RP
RETURN

_TM_DISP4
MOVLW _CMD_AUTO_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CLRF _TM_NAK
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
MOVLW _NUM_DIGITS
CHK?RP _TM_DIG
MOVWF _TM_DIG
MOVLW _START_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
NXDIG
;MOVIW FSR0 ++
MOVF INDF0,W
INCF FSR0
CALL SEG_val
CHK?RP _TM_DAT
IORWF _TM_COLON ,W
movwf _TM_DAT
CALL TM_WRITE
CHK?RP _TM_DIG
DECFSZ _TM_DIG,F
GOTO NXDIG
CALL TM_STOP
CHK?RP _TM_BRIGHT
MOVF _TM_BRIGHT ,W
ANDLW 7
IORLW _DISPLAY_ON
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
RST?RP
RETURN
ENDASM
OVERASM:

CALL TM_INIT


ALOOP:
TOGGLE LED
TM_BRIGHT=TM_BRIGHT-1
if TM_BRIGHT>7 then TM_BRIGHT=7
ARRAYWRITE LEDBUFF ,["b- ",#TM_BRIGHT,0]
DISPLED LEDBUFF,0
PAUSE 500
FOR COUNTER=0 TO 255
ARRAYWRITE LEDBUFF ,[hex COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,BLINK
PAUSE 50
NEXT
FOR COUNTER=0 TO 255
IF !(COUNTER//20) THEN BLINK = TM_COLON ^ $80
ARRAYWRITE LEDBUFF ,[sdec COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,BLINK
PAUSE 50
NEXT
goto ALOOP

[Balachandar]

I used your 18F2620 version of the code for TM1637. It compiles OK, but in the subsequent test with the 18F2620 on a breadboard, the LED lights up and stays lit without anything happening to the LED module. In order to make sure that the PIC is working, I added a For-Next loop to make the LED blink 3 times for 500mS each as a diagnostic routine before the main code executes. Now, the LED blinks correctly telling me that the PIC is working properly at 32MHz. But this is what happens: 3 Blinks, gap of 1 second, 3 blinks and so on. I feel, the PIC is getting reset repeatedly.

Then I tried your original code with 12F1840. The compilation goes through without any errors. But when tested with the LED module, the LED stays lit and the TM1637 LED module does not light up.

Please let me know if you want me to post the code I used for the two PICs.

[richard]

Then I tried your original code with 12F1840. The compilation goes through without any errors. But when tested with the LED module, the LED stays lit and the TM1637 LED module does not light up.

Please let me know if you want me to post the code I used for the two PICs.

this works for me ,its for a 12f1822 and should run on a 12f1840 as is

if you post your code I will look at it,



'************************************************* ***************
'* Name :tm1637-demo.PBP *
'* Author : richard *
'* Notice : *
'* : *
'* Date : *
'* Version : *
'* Notes : PIC12f1822 *
'* : dio on RA1 clk RA2 *
'************************************************* ***************

#CONFIG
__config _CONFIG1, _FOSC_INTOSC & _WDTE_ON & _PWRTE_OFF & _MCLRE_ON & _CP_OFF & _CPD_OFF & _BOREN_ON & _CLKOUTEN_OFF & _IESO_ON & _FCMEN_ON
__config _CONFIG2, _WRT_OFF & _PLLEN_OFF & _STVREN_ON & _BORV_19 & _LVP_OFF
#ENDCONFIG

OSCCON = %01111000 '16MHz HF, software PLL disabled
DEFINE OSC 16
ANSELA=0


USERCOMMAND "DISPLED" ; BUFFER{,COLON } TAKES 150uS FOR 4 DIGITS
USERCOMMAND "STRLEN" ; BUFFER
USERCOMMAND "RJUSTBUFF" ; BUFFER
;ALL NEED TO BE IN SAME BANK
TM_BIT VAR BYTE BANK0
TM_DAT VAR BYTE BANK0
TM_NAK VAR BYTE BANK0 ;set to $80 if tx error occured
TM_DIG VAR BYTE BANK0
TM_BRIGHT VAR BYTE BANK0 ;display pwm level 0 to 7
TM_COLON VAR BYTE BANK0 ;display colon 0/1
TM_TMP VAR BYTE[2] BANK0
str_len VAR BYTE BANK0
;tm1637 CONSTANTS
CMD_AUTO_ADDR CON $40
START_ADDR CON $c0
NUM_DIGITS CON 4 ;number of 7seg leds
COLON_FLAG CON $80
DISPLAY_ON CON $88
;tm1637 DIO AND CLK NEED TO BE ON SAME PORT
@TM_OUT_PORT = LATA ;TM_DIO OUT
@TM_IN_PORT = PORTA ;TM_DIO IN
@TM_CLK = 2 ;PIN
@TM_DIO = 1 ;PIN
@TM_TRIS = TRISA

BLINK VAR BYTE
LEDBUFF VAR BYTE[NUM_DIGITS +1]
COUNTER VAR byte

GOTO OVERASM

ASM
DISPLED?B macro BUFFER
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
L?CALL _TM_DISP4
endm
DISPLED?BC macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
CHK?RP _TM_COLON
MOVE?CB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
DISPLED?BB macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
CHK?RP _TM_COLON
MOVE?BB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
STRLEN?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
L?CALL STRlen
endm
RJUSTBUFF?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
CHK?RP _TM_TMP
MOVE?CB low BUF, _TM_TMP ;load low byte
MOVE?CB HIGH BUF, _TM_TMP+1 ;load low byte
L?CALL STRlen
L?CALL _strpad
endm


STRlen ;get buffer usage size
CHK?RP _str_len
CLRF _str_len
str_tok_chr
MOVIW FSR0 ++ ; Get character
btfsC STATUS,Z
goto exit_str_null ; EXIT ON Null char
INCF _str_len,F ; not null so increment index
goto str_tok_chr
exit_str_null
BANKSEL 0
return
_strpad ;right justify by padding with spaces " "
CHK?RP _str_len
movlw _NUM_DIGITS+1 ;buffer size
subwf _str_len,f ;tx string size
btfsc STATUS, C ;tx string size gotcha
goto expd ;if positive difference then exit buffer overrun will occur ;tx string size gotcha
comf _str_len,f ;the difference is number of spaces to SHIFT in
btfsc STATUS, Z
goto expd ;if zero difference then exit
movlw _NUM_DIGITS ;buffer size
addwf _TM_TMP,f ;add NUM_DIGITS to addr of buffer
nxpd
movf _TM_TMP,w ;low (addr of buffer + NUM_DIGITS )
MOVWF FSR0L
movwf FSR1L
movf _TM_TMP+1,w ;high (addr of buffer + NUM_DIGITS )
MOVWF FSR0H
movwf FSR1H
DECF FSR0L,F ;offset pointer 0
movlw _NUM_DIGITS
movwf _TM_BIT
nxby ;buffer shift right x 1
MOVIW FSR0 --
MOVWI FSR1 --
DECFSZ _TM_BIT,F
GOTO nxby
movlw 0x20
MOVWI FSR1 -- ;poke a space in buff[0]
DECFSZ _str_len,F ;need another one ?
goto nxpd
expd ;nah!
BANKSEL 0
return

SEG_val ;VALID INPUT 0-9 ,A-F, a-f ," " ,-
CHK?RP _TM_TMP
MOVWF _TM_TMP
SUBLW 0x21
btfsc STATUS, C
retlw 0 ;" "
MOVF _TM_TMP,W
SUBLW 0x2f
btfsc STATUS, C
retlw 64 ;"-"
MOVF _TM_TMP,W
MOVLW 0X40
SUBWF _TM_TMP,W
btfsC STATUS, C
GOTO TM_ALPHA
MOVF _TM_TMP,W
ANDLW 0X0F
GOTO TM_LU
TM_ALPHA
ANDLW 0xdf ;ucase
SUBLW 6
btfsS STATUS, C
retlw 0 ;ERROR
MOVLW 0X37
SUBWF _TM_TMP,W
ANDLW 0xdf ;ucase
TM_LU
BRW
retlw 0X3F ;0
retlw 6
retlw 0X5B
retlw 0X4F
retlw 0X66
retlw 0X6D
retlw 0X7D
retlw 7
retlw 0X7F
retlw 0X67 ;9
retlw 0X77 ;A
retlw 0X7C ;b
retlw 0X39 ;C
retlw 0X5E ;d
retlw 0X79 ;E
retlw 0X71 ;F

TM_START
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
BSF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_CLK
;NOP
RETURN

TM_STOP
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
BCF TM_OUT_PORT,TM_DIO
NOP
BSF TM_OUT_PORT,TM_CLK
NOP
BSF TM_OUT_PORT,TM_DIO
;NOP
RETURN

TM_WRITE
MOVLW 8
CHK?RP _TM_BIT
MOVWF _TM_BIT
NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP _TM_DAT
BTFSS _TM_DAT,0
GOTO TM_0
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_DIO
GOTO TM_NB
TM_0
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_DIO
TM_NB
CHK?RP _TM_DAT
RRF _TM_DAT,F
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
CHK?RP _TM_BIT
DECFSZ _TM_BIT,F
GOTO NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BSF TM_TRIS,TM_DIO
CHK?RP TM_IN_PORT
BTFSC TM_IN_PORT,TM_DIO
BSF _TM_NAK,7
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
NOP
NOP
NOP
NOP
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
BANKSEL 0
RETURN
_TM_INIT
CHK?RP _TM_COLON
CLRF _TM_COLON
CLRF _TM_BRIGHT
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
BCF TM_TRIS ,TM_CLK
BANKSEL 0
RETURN

_TM_DISP4
CHK?RP _TM_DAT
MOVLW _CMD_AUTO_ADDR
MOVWF _TM_DAT
CLRF _TM_NAK
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
MOVLW _NUM_DIGITS
CHK?RP _TM_DIG
MOVWF _TM_DIG
MOVLW _START_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
NXDIG
MOVIW FSR0 ++
CALL SEG_val
CHK?RP _TM_DAT
IORWF _TM_COLON ,W
movwf _TM_DAT
CALL TM_WRITE
CHK?RP _TM_DIG
DECFSZ _TM_DIG,F
GOTO NXDIG
CALL TM_STOP
CHK?RP _TM_BRIGHT
MOVF _TM_BRIGHT ,W
ANDLW 7
IORLW _DISPLAY_ON
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
BANKSEL 0
RETURN
ENDASM
OVERASM:

CALL TM_INIT

ALOOP:

TM_BRIGHT=TM_BRIGHT-1
if TM_BRIGHT>7 then TM_BRIGHT=7
ARRAYWRITE LEDBUFF ,["b- ",#TM_BRIGHT,0]
DISPLED LEDBUFF,0
PAUSE 500
FOR COUNTER=0 TO 255
ARRAYWRITE LEDBUFF ,[dec COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,0
PAUSE 50
NEXT
FOR COUNTER=0 TO 255
IF !(COUNTER//20) THEN BLINK = TM_COLON ^ COLON_FLAG
ARRAYWRITE LEDBUFF ,[sdec COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,BLINK
PAUSE 50
NEXT
GOTO ALOOP

[Balachandar]

Compiled your code for 12F1822 for 12F1840 after adding the 'Blink LED 3 times' routine. Compilation went through without a hitch followed by programming a 12F1840. When tested, the LED blinks 3 times and goes off. Nothing else happens.

Compiled once again, this time changing the uC to 12F1822 in MC Studio. Again, the compilation went through fine. But on testing, the LED blinks and goes off, but the LED module does not come to life.

There is one more strange thing I am encountering. A month back, I bought 5 pieces of 12F1840-I/SN (SOIC package) from Ali Exp for $ 3.22. The laser printing/etching on the chip clearly shows "12F1840" and it works at 5V without any problem. But PICKIT2 identifies it as 12LF1840 and the voltage will not go beyond 3.6V. Of course, even if I use an LF version of the PIC, the TM1637 LED module should work. Every now and then, I connect the module to a Nano and check in order to make sure that there is nothing wrong with the module. Whether the voltage is 5 or 3.3, the module works fine. Understandably, the brightness is less at 3.3V.

Code used with 12F1840:


' 12F1840 Pinout:
' -------------------------------------------------------
' VDD VSS
' PortA.5 = Not_used PortA.0 = LED
' PortA.4 = Not_used PortA.1 = DIO
' PortA.3 = Not_used PortA.2 = CLK
' -------------------------------------------------------

#CONFIG
__config _CONFIG1, _FOSC_INTOSC & _MCLRE_ON & _CP_OFF & _CPD_OFF
__config _CONFIG2, _PLLEN_OFF & _LVP_OFF
#ENDCONFIG

OSCCON = %01111000 '16MHz HF, software PLL disabled
DEFINE OSC 16

'Port direction
TRISA = %001000 'A.3 is input, rest are outputs.

ANSELA = 0 'Disable A to D
CM1CON0 = 0 'Disable comparator


USERCOMMAND "DISPLED" ; BUFFER{,COLON } TAKES 150uS FOR 4 DIGITS
USERCOMMAND "STRLEN" ; BUFFER
USERCOMMAND "RJUSTBUFF" ; BUFFER
;ALL NEED TO BE IN SAME BANK
TM_BIT VAR BYTE BANK0
TM_DAT VAR BYTE BANK0
TM_NAK VAR BYTE BANK0 ;set to $80 if tx error occured
TM_DIG VAR BYTE BANK0
TM_BRIGHT VAR BYTE BANK0 ;display pwm level 0 to 7
TM_COLON VAR BYTE BANK0 ;display colon 0/1
TM_TMP VAR BYTE[2] BANK0
str_len VAR BYTE BANK0

;tm1637 CONSTANTS
CMD_AUTO_ADDR CON $40
START_ADDR CON $c0
NUM_DIGITS CON 4 ;number of 7seg leds
COLON_FLAG CON $80
DISPLAY_ON CON $88
;tm1637 DIO AND CLK NEED TO BE ON SAME PORT
@TM_OUT_PORT = LATA ;TM_DIO OUT
@TM_IN_PORT = PORTA ;TM_DIO IN
@TM_CLK = 2 ;PIN
@TM_DIO = 1 ;PIN
@TM_TRIS = TRISA

BLINK VAR BYTE
LEDBUFF VAR BYTE[NUM_DIGITS +1]
COUNTER VAR byte
Cnt var byte ;for use in loops

LED var LATA.0

'Diagnostic routine
DiagRoutine:
for cnt = 1 to 3 'Blink LED 3 times.
led = 1 : pause 500
led = 0 : pause 500
next cnt


GOTO OVERASM

ASM
DISPLED?B macro BUFFER
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
L?CALL _TM_DISP4
endm
DISPLED?BC macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
CHK?RP _TM_COLON
MOVE?CB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
DISPLED?BB macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
CHK?RP _TM_COLON
MOVE?BB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
STRLEN?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
L?CALL STRlen
endm
RJUSTBUFF?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
CHK?RP _TM_TMP
MOVE?CB low BUF, _TM_TMP ;load low byte
MOVE?CB HIGH BUF, _TM_TMP+1 ;load low byte
L?CALL STRlen
L?CALL _strpad
endm


STRlen ;get buffer usage size
CHK?RP _str_len
CLRF _str_len
str_tok_chr
MOVIW FSR0 ++ ; Get character
btfsC STATUS,Z
goto exit_str_null ; EXIT ON Null char
INCF _str_len,F ; not null so increment index
goto str_tok_chr
exit_str_null
BANKSEL 0
return
_strpad ;right justify by padding with spaces " "
CHK?RP _str_len
movlw _NUM_DIGITS+1 ;buffer size
subwf _str_len,f ;tx string size
btfsc STATUS, C ;tx string size gotcha
goto expd ;if positive difference then exit buffer overrun will occur ;tx string size gotcha
comf _str_len,f ;the difference is number of spaces to SHIFT in
btfsc STATUS, Z
goto expd ;if zero difference then exit
movlw _NUM_DIGITS ;buffer size
addwf _TM_TMP,f ;add NUM_DIGITS to addr of buffer
nxpd
movf _TM_TMP,w ;low (addr of buffer + NUM_DIGITS )
MOVWF FSR0L
movwf FSR1L
movf _TM_TMP+1,w ;high (addr of buffer + NUM_DIGITS )
MOVWF FSR0H
movwf FSR1H
DECF FSR0L,F ;offset pointer 0
movlw _NUM_DIGITS
movwf _TM_BIT
nxby ;buffer shift right x 1
MOVIW FSR0 --
MOVWI FSR1 --
DECFSZ _TM_BIT,F
GOTO nxby
movlw 0x20
MOVWI FSR1 -- ;poke a space in buff[0]
DECFSZ _str_len,F ;need another one ?
goto nxpd
expd ;nah!
BANKSEL 0
return

SEG_val ;VALID INPUT 0-9 ,A-F, a-f ," " ,-
CHK?RP _TM_TMP
MOVWF _TM_TMP
SUBLW 0x21
btfsc STATUS, C
retlw 0 ;" "
MOVF _TM_TMP,W
SUBLW 0x2f
btfsc STATUS, C
retlw 64 ;"-"
MOVF _TM_TMP,W
MOVLW 0X40
SUBWF _TM_TMP,W
btfsC STATUS, C
GOTO TM_ALPHA
MOVF _TM_TMP,W
ANDLW 0X0F
GOTO TM_LU
TM_ALPHA
ANDLW 0xdf ;ucase
SUBLW 6
btfsS STATUS, C
retlw 0 ;ERROR
MOVLW 0X37
SUBWF _TM_TMP,W
ANDLW 0xdf ;ucase
TM_LU
BRW
retlw 0X3F ;0
retlw 6
retlw 0X5B
retlw 0X4F
retlw 0X66
retlw 0X6D
retlw 0X7D
retlw 7
retlw 0X7F
retlw 0X67 ;9
retlw 0X77 ;A
retlw 0X7C ;b
retlw 0X39 ;C
retlw 0X5E ;d
retlw 0X79 ;E
retlw 0X71 ;F

TM_START
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
BSF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_CLK
;NOP
RETURN

TM_STOP
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
BCF TM_OUT_PORT,TM_DIO
NOP
BSF TM_OUT_PORT,TM_CLK
NOP
BSF TM_OUT_PORT,TM_DIO
;NOP
RETURN

TM_WRITE
MOVLW 8
CHK?RP _TM_BIT
MOVWF _TM_BIT
NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP _TM_DAT
BTFSS _TM_DAT,0
GOTO TM_0
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_DIO
GOTO TM_NB
TM_0
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_DIO
TM_NB
CHK?RP _TM_DAT
RRF _TM_DAT,F
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
CHK?RP _TM_BIT
DECFSZ _TM_BIT,F
GOTO NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BSF TM_TRIS,TM_DIO
CHK?RP TM_IN_PORT
BTFSC TM_IN_PORT,TM_DIO
BSF _TM_NAK,7
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
NOP
NOP
NOP
NOP
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
BANKSEL 0
RETURN
_TM_INIT
CHK?RP _TM_COLON
CLRF _TM_COLON
CLRF _TM_BRIGHT
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
BCF TM_TRIS ,TM_CLK
BANKSEL 0
RETURN

_TM_DISP4
CHK?RP _TM_DAT
MOVLW _CMD_AUTO_ADDR
MOVWF _TM_DAT
CLRF _TM_NAK
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
MOVLW _NUM_DIGITS
CHK?RP _TM_DIG
MOVWF _TM_DIG
MOVLW _START_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
NXDIG
MOVIW FSR0 ++
CALL SEG_val
CHK?RP _TM_DAT
IORWF _TM_COLON ,W
movwf _TM_DAT
CALL TM_WRITE
CHK?RP _TM_DIG
DECFSZ _TM_DIG,F
GOTO NXDIG
CALL TM_STOP
CHK?RP _TM_BRIGHT
MOVF _TM_BRIGHT ,W
ANDLW 7
IORLW _DISPLAY_ON
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
BANKSEL 0
RETURN
ENDASM
OVERASM:

CALL TM_INIT

ALOOP:

TM_BRIGHT=TM_BRIGHT-1
if TM_BRIGHT>7 then TM_BRIGHT=7
ARRAYWRITE LEDBUFF ,["b- ",#TM_BRIGHT,0]
DISPLED LEDBUFF,0
PAUSE 500
FOR COUNTER=0 TO 255
ARRAYWRITE LEDBUFF ,[dec COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,0
PAUSE 50
NEXT
FOR COUNTER=0 TO 255
IF !(COUNTER//20) THEN BLINK = TM_COLON ^ COLON_FLAG
ARRAYWRITE LEDBUFF ,[sdec COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,BLINK
PAUSE 50
NEXT
GOTO ALOOP

[richard]

Compiled your code for 12F1822 for 12F1840 after adding the 'Blink LED 3 times' routine. Compilation went through without a hitch followed by programming a 12F1840. When tested, the LED blinks 3 times and goes off. Nothing else happens.

WORKS just fine for me, even at 3v




pic18 version [can't believe how many changes it needed]


'************************************************* ***************
'* Name :tm1637-demo.PBP *
'* Author : richard *
'* Notice : *
'* : *
'* Date : *
'* Version : *
'* Notes : PIC18F45K20 *
'* : dio on RB0 clk RB1 *
'************************************************* ***************

#CONFIG
CONFIG FOSC = INTIO67
CONFIG FCMEN = OFF
CONFIG IESO = OFF
CONFIG PWRT = OFF
CONFIG BOREN = SBORDIS
CONFIG BORV = 18
CONFIG WDTEN = ON
CONFIG WDTPS = 512
CONFIG CCP2MX = PORTC
CONFIG PBADEN = OFF
CONFIG LPT1OSC = OFF
CONFIG HFOFST = ON
CONFIG MCLRE = ON
CONFIG STVREN = ON
CONFIG LVP = OFF
CONFIG XINST = OFF
CONFIG DEBUG = OFF
CONFIG CP0 = OFF
CONFIG CP1 = OFF
CONFIG CP2 = OFF
CONFIG CP3 = OFF
CONFIG CPB = OFF
CONFIG CPD = OFF
CONFIG WRT0 = OFF
CONFIG WRT1 = OFF
CONFIG WRT2 = OFF
CONFIG WRT3 = OFF
CONFIG WRTC = OFF
CONFIG WRTB = OFF
CONFIG WRTD = OFF
CONFIG EBTR0 = OFF
CONFIG EBTR1 = OFF
CONFIG EBTR2 = OFF
CONFIG EBTR3 = OFF
CONFIG EBTRB = OFF
#ENDCONFIG
DEFINE OSC 32

osccon=$60 '32 mhz
OSCTUNE.6=1

trisb.4=0
ANSELH=0
LED VAR PORTB.4 ' Assign name "LED" to

USERCOMMAND "DISPLED" ; BUFFER{,COLON }
USERCOMMAND "STRLEN" ; BUFFER
USERCOMMAND "RJUSTBUFF" ; BUFFER

TM_BIT VAR BYTE BANK0
TM_DAT VAR BYTE BANK0
TM_NAK VAR BYTE BANK0 ;set to $80 if tx error occured
TM_DIG VAR BYTE BANK0
TM_BRIGHT VAR BYTE BANK0 ;display pwm level 0 to 7
TM_COLON VAR BYTE BANK0 ;display colon 0/1
TM_TMP VAR BYTE[2] BANK0
str_len VAR BYTE BANK0

CMD_AUTO_ADDR CON $40
START_ADDR CON $c0
NUM_DIGITS CON 4 ;number of 7seg leds
COLON_FLAG CON $80
DISPLAY_ON CON $88
;tm1637 DIO AND CLK NEED TO BE ON SAME PORT
@TM_OUT_PORT = LATB ;TM_DIO OUT
@TM_IN_PORT = PORTB ;TM_DIO IN
@TM_CLK = 1 ;PIN
@TM_DIO = 0 ;PIN
@TM_TRIS = TRISB

BLINK VAR BYTE
LEDBUFF VAR BYTE[NUM_DIGITS +1]
COUNTER VAR BYTE

GOTO OVERASM

ASM
DISPLED?B macro BUFFER
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
L?CALL _TM_DISP4
endm
DISPLED?BC macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
MOVE?CB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
DISPLED?BB macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
MOVE?BB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
STRLEN?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
L?CALL STRlen
endm
RJUSTBUFF?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
MOVE?CB low BUF, _TM_TMP ;load low byte
MOVE?CB HIGH BUF, _TM_TMP+1 ;load low byte
L?CALL STRlen
L?CALL _strpad
endm





STRlen ;get buffer usage size
CLRF _str_len
str_tok_chr
;MOVIW FSR0 ++ ; Get character
MOVF INDF0,W
INFSNZ FSR0L
incf FSR0H
btfsC STATUS,Z
goto exit_str_null ; EXIT ON Null char
INCF _str_len,F ; not null so increment index
goto str_tok_chr
exit_str_null
return


_strpad ;right justify by padding with spaces " "
BANKSEL 0
MOVLW 5
;ADDWF _str_field_size,w ;buffer size
subwf _str_len,f ;tx string size
btfsc STATUS, C ;tx string size gotcha
goto expd ;if positive difference then exit buffer overrun will occur ;tx string size gotcha
comf _str_len ;the difference is number of spaces to SHIFT in
btfsc STATUS, Z
goto expd ;if zero difference then exit
moVLW 4 ;buffer size
addwf _TM_TMP,f ;add NUM_DIGITS to addr of buffer
;btfsc STATUS, C
;INCF _STR_TMP+1,f
nxpd
movf _TM_TMP,w ;low (addr of buffer + NUM_DIGITS )
MOVWF FSR0L
movwf FSR1L
DECF FSR0L,F ;offset pointer 0
;btfsc STATUS, C
;DECF FSR0H,F
movf _TM_TMP+1,w ;high (addr of buffer + NUM_DIGITS )
MOVWF FSR0H
movwf FSR1H
MOVLW 4
movwf _TM_BIT
nxby ;buffer shift right x 1
ifdef TBLPTRL ;fsr
movf POSTDEC0, W ;[pic18]
MOVWF POSTDEC1
else
MOVIW FSR0 --
MOVWI FSR1 --
endif
DECFSZ _TM_BIT,F
GOTO nxby
movlw 0x20
ifdef TBLPTRL ;fsr
MOVWF POSTDEC1
else
MOVWI FSR1 --
endif
DECFSZ _str_len,F ;need another one ?
goto nxpd
expd ;nah!
BANKSEL 0
return
SEG_val
CHK?RP _TM_TMP
MOVWF _TM_TMP
CLRF _TM_TMP +1
SUBLW 0x21
btfsc STATUS, C
retlw 0 ;" "
MOVF _TM_TMP,W
SUBLW 0x2f
btfsc STATUS, C
retlw 64 ;"-"
MOVF _TM_TMP,W
MOVLW 0X40
SUBWF _TM_TMP,W
btfsC STATUS, C
GOTO TM_ALPHA
MOVF _TM_TMP,W
ANDLW 0X0F
GOTO TM_LU
TM_ALPHA
ANDLW 0xdf ;ucase
SUBLW 6
btfsS STATUS, C
retlw 0 ;ERROR
MOVLW 0X37
SUBWF _TM_TMP,W
ANDLW 0xdf ;ucase
TM_LU
addlw LOW TABLE_START
movwf TBLPTRL
rlcf _TM_TMP +1 ,w
addlw HIGH TABLE_START
movwf TBLPTRH
movlw UPPER TABLE_START
movwf TBLPTRU
tblrd *+
movf TABLAT,w
return


TABLE_START
db 0X3F,6,0X5B,0X4F,0X66,0X6D,0X7D,7,0X7F,0X67,0X77 ,0X7C ,0X39 ,0X5E ,0X79 ,0X71


TM_START
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
BSF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_CLK
NOP
RETURN

TM_STOP
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
BCF TM_OUT_PORT,TM_DIO
NOP
BSF TM_OUT_PORT,TM_CLK
NOP
BSF TM_OUT_PORT,TM_DIO
NOP
RETURN

TM_WRITE
MOVLW 8
CHK?RP _TM_BIT
MOVWF _TM_BIT
NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP _TM_DAT
BTFSS _TM_DAT,0
GOTO TM_0
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_DIO
GOTO TM_NB
TM_0
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_DIO
TM_NB
CHK?RP _TM_DAT
RRCF _TM_DAT,F
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
CHK?RP _TM_BIT
DECFSZ _TM_BIT,F
GOTO NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BSF TM_TRIS,TM_DIO
CHK?RP TM_IN_PORT
BTFSC TM_IN_PORT,TM_DIO
BSF _TM_NAK,7
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
NOP
NOP
NOP
NOP
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
RST?RP
RETURN
_TM_INIT
CHK?RP _TM_COLON
CLRF _TM_COLON
CLRF _TM_BRIGHT
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
BCF TM_TRIS ,TM_CLK
RST?RP
RETURN

_TM_DISP4
MOVLW _CMD_AUTO_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CLRF _TM_NAK
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
MOVLW _NUM_DIGITS
CHK?RP _TM_DIG
MOVWF _TM_DIG
MOVLW _START_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
NXDIG
;MOVIW FSR0 ++
MOVF INDF0,W
INFSNZ FSR0L
incf FSR0H
CALL SEG_val
CHK?RP _TM_DAT
IORWF _TM_COLON ,W
movwf _TM_DAT
CALL TM_WRITE
CHK?RP _TM_DIG
DECFSZ _TM_DIG,F
GOTO NXDIG
CALL TM_STOP
CHK?RP _TM_BRIGHT
MOVF _TM_BRIGHT ,W
ANDLW 7
IORLW _DISPLAY_ON
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
RST?RP
RETURN


_TM_DISP1 ; WRITES TO A DISP POSN TM_TMP HOLDS DATA FOR TM_DIG IS POSN 0-3
CHK?RP _TM_DAT
MOVLW _CMD_AUTO_ADDR
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
MOVLW _START_ADDR
addwf _TM_DIG,W
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CHK?RP _TM_TMP
MOVF _TM_TMP,W
movwf _TM_DAT
CALL TM_WRITE
CALL TM_STOP
BANKSEL 0
RETURN







ENDASM
OVERASM:
FOR COUNTER=0 TO 3
TOGGLE LED
PAUSE 500
next
CALL TM_INIT
BLINK=0

ALOOP:
TOGGLE LED
TM_BRIGHT=TM_BRIGHT-1
if TM_BRIGHT>7 then TM_BRIGHT=7
ARRAYWRITE LEDBUFF ,["B- ",#TM_BRIGHT]

DISPLED LEDBUFF,0


PAUSE 500
FOR COUNTER=0 TO 255
ARRAYWRITE LEDBUFF ,[hex COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,0
PAUSE 50
NEXT
FOR COUNTER=0 TO 255
IF !(COUNTER//20) THEN BLINK = TM_COLON ^ $80
ARRAYWRITE LEDBUFF ,[sdec COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,BLINK
PAUSE 50
NEXT
goto ALOOP

[Balachandar]

WOW! FINALLY, IT HAPPENED!!

The TM1637 LED display module came alive!!!
I used your revised code for 18F devices and after I made a few changes in the CONFIG section, the compilation for 18F2620 was successful.
I programmed and inserted the PIC in the breadboard and powered it up. After the LED blinked 3 times, it was a real pleasant sight to see the digits appear on the LED module.
Thanks a lot Richard, for your patience and helping nature.

The code I used for 18F2620 is reproduced below.
OSCCON = $60; OSCTUNE.6 = 1 - These two settings in your code make the Osc 16Mhz (4MHz x 4). So, I changed the Osc speed from 32 to 16MHz. Later, I tried the code at 8MHz and 4MHz. It works beautifully at those speeds too.


'-------------------------------------------------------------------------------
'PIC used: 18F2620
'Pinout
' ---------
' E.3 = 1 28 B.7 =
' A.0 = 2 27 B.6 =
' A.1 = 3 26 B.5 =
' A.2 = 4 25 B.4 = LED
' A.3 = 5 24 B.3 =
' A.4 = 6 23 B.2 =
' A.5 = 7 22 B.1 = CLK
' Gnd 8 21 B.0 = DIO
' A.7 = 9 20 +5V
' A.6 = 10 19 Gnd
' C.0 = 11 18 C.7 =
' C.1 = 12 17 C.6 =
' C.2 = 13 16 C.5 =
' C.3 = 14 15 C.4 =
' ---------
'-------------------------------------------------------------------------------
#CONFIG
CONFIG OSC = INTIO67 ; CONFIG FOSC = INTIO67
CONFIG FCMEN = OFF
CONFIG IESO = OFF
CONFIG PWRT = OFF
CONFIG BOREN = SBORDIS
CONFIG BORV = 2 ; CONFIG BORV = 18
CONFIG WDT = ON ; CONFIG WDTEN = ON
CONFIG WDTPS = 512
CONFIG CCP2MX = PORTC
CONFIG PBADEN = OFF
CONFIG LPT1OSC = OFF
; CONFIG HFOFST = ON ;Not applicable to 18F2620
CONFIG MCLRE = ON
CONFIG STVREN = ON
CONFIG LVP = OFF
CONFIG XINST = OFF
CONFIG DEBUG = OFF
CONFIG CP0 = OFF
CONFIG CP1 = OFF
CONFIG CP2 = OFF
CONFIG CP3 = OFF
CONFIG CPB = OFF
CONFIG CPD = OFF
CONFIG WRT0 = OFF
CONFIG WRT1 = OFF
CONFIG WRT2 = OFF
CONFIG WRT3 = OFF
CONFIG WRTC = OFF
CONFIG WRTB = OFF
CONFIG WRTD = OFF
CONFIG EBTR0 = OFF
CONFIG EBTR1 = OFF
CONFIG EBTR2 = OFF
CONFIG EBTR3 = OFF
CONFIG EBTRB = OFF
#ENDCONFIG

OSCCON = $60 '4 mhz
OSCTUNE.6 = 1 'PLL Enabled

DEFINE OSC 16 '16MHz (4X4 = 16)

TRISB.4=0
' ANSELH=0 'Not applicable to 18F2620
ADCON1 = 15 'Disable ADC

LED VAR PORTB.4 ' Assign name "LED" to

USERCOMMAND "DISPLED" ; BUFFER{,COLON }
USERCOMMAND "STRLEN" ; BUFFER
USERCOMMAND "RJUSTBUFF" ; BUFFER

TM_BIT VAR BYTE BANK0
TM_DAT VAR BYTE BANK0
TM_NAK VAR BYTE BANK0 ;set to $80 if tx error occured
TM_DIG VAR BYTE BANK0
TM_BRIGHT VAR BYTE BANK0 ;display pwm level 0 to 7
TM_COLON VAR BYTE BANK0 ;display colon 0/1
TM_TMP VAR BYTE[2] BANK0
str_len VAR BYTE BANK0

CMD_AUTO_ADDR CON $40
START_ADDR CON $c0
NUM_DIGITS CON 4 ;number of 7seg leds
COLON_FLAG CON $80
DISPLAY_ON CON $88
;tm1637 DIO AND CLK NEED TO BE ON SAME PORT
@TM_OUT_PORT = LATB ;TM_DIO OUT
@TM_IN_PORT = PORTB ;TM_DIO IN
@TM_CLK = 1 ;PIN
@TM_DIO = 0 ;PIN
@TM_TRIS = TRISB

BLINK VAR BYTE
LEDBUFF VAR BYTE[NUM_DIGITS +1]
COUNTER VAR BYTE

GOTO OVERASM

ASM
DISPLED?B macro BUFFER
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
L?CALL _TM_DISP4
endm
DISPLED?BC macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
MOVE?CB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
DISPLED?BB macro BUFFER ,COLON
movlw low BUFFER
movwf FSR0L
movlw high BUFFER
movwf FSR0H
MOVE?BB COLON ,_TM_COLON
L?CALL _TM_DISP4
endm
STRLEN?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
L?CALL STRlen
endm
RJUSTBUFF?B macro BUF
MOVE?CB high BUF, FSR0H ;load highbyte
MOVE?CB low BUF, FSR0L ;load low byte
MOVE?CB low BUF, _TM_TMP ;load low byte
MOVE?CB HIGH BUF, _TM_TMP+1 ;load low byte
L?CALL STRlen
L?CALL _strpad
endm





STRlen ;get buffer usage size
CLRF _str_len
str_tok_chr
;MOVIW FSR0 ++ ; Get character
MOVF INDF0,W
INFSNZ FSR0L
incf FSR0H
btfsC STATUS,Z
goto exit_str_null ; EXIT ON Null char
INCF _str_len,F ; not null so increment index
goto str_tok_chr
exit_str_null
return


_strpad ;right justify by padding with spaces " "
BANKSEL 0
MOVLW 5
;ADDWF _str_field_size,w ;buffer size
subwf _str_len,f ;tx string size
btfsc STATUS, C ;tx string size gotcha
goto expd ;if positive difference then exit buffer overrun will occur ;tx string size gotcha
comf _str_len ;the difference is number of spaces to SHIFT in
btfsc STATUS, Z
goto expd ;if zero difference then exit
moVLW 4 ;buffer size
addwf _TM_TMP,f ;add NUM_DIGITS to addr of buffer
;btfsc STATUS, C
;INCF _STR_TMP+1,f
nxpd
movf _TM_TMP,w ;low (addr of buffer + NUM_DIGITS )
MOVWF FSR0L
movwf FSR1L
DECF FSR0L,F ;offset pointer 0
;btfsc STATUS, C
;DECF FSR0H,F
movf _TM_TMP+1,w ;high (addr of buffer + NUM_DIGITS )
MOVWF FSR0H
movwf FSR1H
MOVLW 4
movwf _TM_BIT
nxby ;buffer shift right x 1
ifdef TBLPTRL ;fsr
movf POSTDEC0, W ;[pic18]
MOVWF POSTDEC1
else
MOVIW FSR0 --
MOVWI FSR1 --
endif
DECFSZ _TM_BIT,F
GOTO nxby
movlw 0x20
ifdef TBLPTRL ;fsr
MOVWF POSTDEC1
else
MOVWI FSR1 --
endif
DECFSZ _str_len,F ;need another one ?
goto nxpd
expd ;nah!
BANKSEL 0
return
SEG_val
CHK?RP _TM_TMP
MOVWF _TM_TMP
CLRF _TM_TMP +1
SUBLW 0x21
btfsc STATUS, C
retlw 0 ;" "
MOVF _TM_TMP,W
SUBLW 0x2f
btfsc STATUS, C
retlw 64 ;"-"
MOVF _TM_TMP,W
MOVLW 0X40
SUBWF _TM_TMP,W
btfsC STATUS, C
GOTO TM_ALPHA
MOVF _TM_TMP,W
ANDLW 0X0F
GOTO TM_LU
TM_ALPHA
ANDLW 0xdf ;ucase
SUBLW 6
btfsS STATUS, C
retlw 0 ;ERROR
MOVLW 0X37
SUBWF _TM_TMP,W
ANDLW 0xdf ;ucase
TM_LU
addlw LOW TABLE_START
movwf TBLPTRL
rlcf _TM_TMP +1 ,w
addlw HIGH TABLE_START
movwf TBLPTRH
movlw UPPER TABLE_START
movwf TBLPTRU
tblrd *+
movf TABLAT,w
return


TABLE_START
db 0X3F,6,0X5B,0X4F,0X66,0X6D,0X7D,7,0X7F,0X67,0X77 ,0X7C ,0X39 ,0X5E ,0X79 ,0X71


TM_START
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
BSF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_DIO
NOP
BCF TM_OUT_PORT,TM_CLK
NOP
RETURN

TM_STOP
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
BCF TM_OUT_PORT,TM_DIO
NOP
BSF TM_OUT_PORT,TM_CLK
NOP
BSF TM_OUT_PORT,TM_DIO
NOP
RETURN

TM_WRITE
MOVLW 8
CHK?RP _TM_BIT
MOVWF _TM_BIT
NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP _TM_DAT
BTFSS _TM_DAT,0
GOTO TM_0
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_DIO
GOTO TM_NB
TM_0
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_DIO
TM_NB
CHK?RP _TM_DAT
RRCF _TM_DAT,F
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
CHK?RP _TM_BIT
DECFSZ _TM_BIT,F
GOTO NXBT
CHK?RP TM_OUT_PORT
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BSF TM_TRIS,TM_DIO
CHK?RP TM_IN_PORT
BTFSC TM_IN_PORT,TM_DIO
BSF _TM_NAK,7
CHK?RP TM_OUT_PORT
BSF TM_OUT_PORT,TM_CLK
NOP
NOP
NOP
NOP
BCF TM_OUT_PORT,TM_CLK
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
RST?RP
RETURN
_TM_INIT
CHK?RP _TM_COLON
CLRF _TM_COLON
CLRF _TM_BRIGHT
CHK?RP TM_TRIS
BCF TM_TRIS ,TM_DIO
BCF TM_TRIS ,TM_CLK
RST?RP
RETURN

_TM_DISP4
MOVLW _CMD_AUTO_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CLRF _TM_NAK
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
MOVLW _NUM_DIGITS
CHK?RP _TM_DIG
MOVWF _TM_DIG
MOVLW _START_ADDR
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
NXDIG
;MOVIW FSR0 ++
MOVF INDF0,W
INFSNZ FSR0L
incf FSR0H
CALL SEG_val
CHK?RP _TM_DAT
IORWF _TM_COLON ,W
movwf _TM_DAT
CALL TM_WRITE
CHK?RP _TM_DIG
DECFSZ _TM_DIG,F
GOTO NXDIG
CALL TM_STOP
CHK?RP _TM_BRIGHT
MOVF _TM_BRIGHT ,W
ANDLW 7
IORLW _DISPLAY_ON
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
RST?RP
RETURN


_TM_DISP1 ; WRITES TO A DISP POSN TM_TMP HOLDS DATA FOR TM_DIG IS POSN 0-3
CHK?RP _TM_DAT
MOVLW _CMD_AUTO_ADDR
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CALL TM_STOP
MOVLW _START_ADDR
addwf _TM_DIG,W
CHK?RP _TM_DAT
MOVWF _TM_DAT
CALL TM_START
CALL TM_WRITE
CHK?RP _TM_TMP
MOVF _TM_TMP,W
movwf _TM_DAT
CALL TM_WRITE
CALL TM_STOP
BANKSEL 0
RETURN







ENDASM
OVERASM:
FOR COUNTER=0 TO 3
TOGGLE LED
PAUSE 500
next
CALL TM_INIT
BLINK=0

ALOOP:
TOGGLE LED
TM_BRIGHT=TM_BRIGHT-1
if TM_BRIGHT>7 then TM_BRIGHT=7
ARRAYWRITE LEDBUFF ,["B- ",#TM_BRIGHT]

DISPLED LEDBUFF,0


PAUSE 500
FOR COUNTER=0 TO 255
ARRAYWRITE LEDBUFF ,[hex COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,0
PAUSE 50
NEXT
FOR COUNTER=0 TO 255
IF !(COUNTER//20) THEN BLINK = TM_COLON ^ $80
ARRAYWRITE LEDBUFF ,[sdec COUNTER,0]
RJUSTBUFF LEDBUFF
DISPLED LEDBUFF,BLINK
PAUSE 50
NEXT
goto ALOOP

[richard]

WOW! FINALLY, IT HAPPENED!!

The TM1637 LED display module came alive!!!
I used your revised code for 18F devices and after I made a few changes in the CONFIG section, the compilation for 18F2620 was successful.


very good. you would have to wonder why the 12f1840 did not work



I changed the Osc speed from 32 to 16MHz. Later, I tried the code at 8MHz and 4MHz. It works beautifully at those speeds too.

the code works up t0 64mhz and can write the 4 digits in less than 50uS