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SOTASOTA
- 5th June 2014, 02:30
Hi there!
I have zero knowledge of assembly code. I got this from a website for an IR Remote Control. I used the supplied HEX file to program a 16F684 to success. My application requires I hold down the momentary buttons to perform Volume + and Volume - operations. However, when I use the code, it only transmits for a few seconds. I have to release then re-press the button. Is there anyone who understand assembly how can alter the code to allow continuous pressing of the buttons?

I am using the 8 channel mode.

Thanks for your help!
Here's the code:



list p=16f684
__CONFIG _CP_OFF & _WDT_ON & _PWRTE_ON & _MCLRE_OFF & _INTRC_OSC_NOCLKOUT & _BOD_OFF & _FCMEN_OFF & _IESO_OFF

; toggle or momentary mode, 8 channels
#define MODE_CH8

; ON/OFF latched mode, 4 channels
;define MODE_CH4

#include <p16F684.inc>
#include <irmtxv4.inc>

variables UDATA
; RAM registers
tcnt RES 1
rcnt RES 1
cod RES 1
prevcod RES 1
cod0 RES 1
rowstate RES 1

startup CODE 0
goto main
nop
nop
nop
retfie

prog CODE

main ; program starts here
movlw 7
movwf CMCON0 ; set outputs digital
BANKSEL ANSEL
clrf ANSEL
movlw 0x17
movwf TRISA
clrf TRISC
movwf WPUA
movwf IOCA
clrf TMR0
bcf OPTION_REG, PSA
clrwdt
movlw (0<<NOT_RAPU)|(0<<T0CS)|(0<<INTEDG)|(0<<PSA)|(0x07)
movwf OPTION_REG ; portA pullups enabled
clrwdt

BANKSEL PORTA
clrf PORTA
clrf PORTC
movlw (1<<RAIE); RA int on change enable
movwf INTCON

call mtx_init
clrf mtx_buffer
clrf tcnt

loop0 clrf (mtx_buffer+1)
movlw 0xff
movwf prevcod ; no button was pressed in the previous scan
movlw 0x1c ;c0,c1=0,c3=1
movwf PORTC
movlw 0x00
tris PORTC
movf PORTA, W
bcf INTCON, RAIF
sleep

loop clrf cod
movlw 0x1d
tris PORTC ; select colA (RC1)
clrf PORTC
#ifdef MODE_CH8
clrw
#endif
#ifdef MODE_CH4
movlw 0x20
#endif
call scan
movlw 0x1e
tris PORTC ; select colB (RC0)
#ifdef MODE_CH8
movlw 0x04
#endif
#ifdef MODE_CH4
movlw 0x30
#endif
call scan
movf cod, W
bz loop2 ; if no buton is pressed, skip

subwf prevcod, W ; if the same button is pressed, skip
bz loop2

movf cod, W
movwf prevcod ; a new button is pressed - rcnt=3
movwf (mtx_buffer+1)
movlw 3
movwf rcnt

movlw 0x40 ; new button - new transmission
addwf tcnt, F

loop2 movlw 0x17
tris PORTC ; select ID (RC3)
call scanid
movf cod0, W
movwf (mtx_buffer)

loop3 movf (mtx_buffer+1), W
andlw 0x3f
iorwf tcnt, W
movwf (mtx_buffer+1)

call mtx_send

movf rcnt, W
bz loop_done
decfsz rcnt, F
goto loop

loop_done movf cod, W
btfsc STATUS, Z
goto loop0 ; no button was pressed, go sleep
; if the same button is being hold, repeat the transmission
goto loop

scan movwf cod0
;movlw 0xc0
scandelay ;addlw 1
;bnz scandelay
movlw 0x17
andwf PORTA, W
movwf rowstate

incf cod0, F
btfss rowstate, 2
goto pressed

incf cod0, F
btfss rowstate, 4
goto pressed

incf cod0, F
btfss rowstate, 0
goto pressed

incf cod0, F
btfss rowstate, 1
goto pressed
retlw 0

pressed movf cod0, W
movwf cod
return

scanid clrf cod0
clrw
scandelay2 addlw 1
bnz scandelay2
movlw 0x17
andwf PORTA, W
movwf rowstate

btfss rowstate, 4
bsf cod0, 3
btfss rowstate, 0
bsf cod0, 2
btfss rowstate, 2
bsf cod0, 1
btfss rowstate, 1
bsf cod0, 0
return

end
Dave
- 5th June 2014, 12:13
Sotasota, There apears to be some code missing?
Demon
- 5th June 2014, 13:59
Wonder what's in here.


#include <irmtxv4.inc>

Robert
SOTASOTA
- 5th June 2014, 14:59
Ooops! Sorry, here is the missing code!! :-)



;************************************************* *********************
; *
; Filename: irmtxv4.inc *
;************************************************* *********************
; Notes:
;
; IR transmitter prot.v4 (Manchester)
;************************************************* *********************

EXTERN mtx_buffer, mtx_delay
EXTERN mtx_init, mtx_send


And:



;************************************************* *********************
; *
; Filename: irmtxv4.asm *
;************************************************* *********************
; Notes:
;
; IR transmitter prot.v4.2 (Manchester)
;************************************************* *********************
;
; header : 20xbit1, 1xbit0
; bytes : 8xbitX, 1xbit1, 1xbit0
;
; packet structure: <data0> <data1> <data2> <checksum>
;
; 020 - library version
; untested!
;
; 021 - add half frame variable
; remove buffer initialization
;
; 030-20050102 codec-v4.2:
; checksum with CRC-8
; T=350 usec
; 3-byte buffer length
;
; 031-20050227 same format for IR
; the TX output is fixed, it uses the hardware PWM output pin
;
;************************************************* *********************

list p=16F684
#include <p16F684.inc>

GLOBAL mtx_buffer, mtx_init, mtx_send, mtx_delay

packet_len EQU 2
pwm_freq EQU d'38000'

;dc_value EQU d'500000' / pwm_freq
;dc1b_value EQU (d'2000000' / pwm_freq) - (4 * dc_value)

; rather use the exact period rate/2 for duty cycle calculation
dc_value EQU (d'1000000' / pwm_freq) >> 1
dc1b_value EQU ( (d'1000000' / pwm_freq) << 1) - (dc_value << 2)

ccp1con_value EQU (1<<CCP1M3) | (1<<CCP1M2) | (dc1b_value << 4)
pr2_value EQU (d'1000000' / pwm_freq) - 1

;***** VARIABLE DEFINITIONS
mtxdata UDATA

count1 res 1
count2 res 1
ncnt res 1
bt res 1
sum res 1
mtx_buffer res 2

mtx_delay res 1 ; half_frame delay

;************************************************* *********************

mtx CODE

mtx_init
BANKSEL T2CON
movlw (1<<TMR2ON) | (0x00)
movwf T2CON ; TMR2 on, 1:1 prescaler
movlw dc_value
movwf CCPR1L ; PWM duty cycle

movlw 0 ; ccp1con_value
movwf CCP1CON ; turn off CCP module

BANKSEL PR2
movlw pr2_value
movwf PR2
BANKSEL PORTA

movlw .117 ; 350 usec
movwf mtx_delay
return
;

mtx_send
; send out buffer
outbuf movlw 0x14 ; 20xbit1, 1xbit0

header movwf count2
head0 call bit1
decfsz count2,F
goto head0
call bit0

movlw mtx_buffer
movwf FSR
movlw packet_len
movwf count1
movlw 0xff
movwf sum
;
outbu0 movf INDF,W
call update_sum
movf INDF,W
call outbyte
incf FSR,F
decfsz count1,F
goto outbu0
movf sum,W
call outbyte
; buffer is sent

return

update_sum ; fast CRC-8 algorithm with poly x^8+x^5+x^4+1
; executes in 23 cycles per update

xorwf sum,f
clrw
btfsc sum,7
xorlw 0x7a
btfsc sum,6
xorlw 0x3d
btfsc sum,5
xorlw 0x86
btfsc sum,4
xorlw 0x43
btfsc sum,3
xorlw 0xb9
btfsc sum,2
xorlw 0xc4
btfsc sum,1
xorlw 0x62
btfsc sum,0
xorlw 0x31
movwf sum
return
;
outbyte movwf bt
movlw 8
movwf count2
outby0 rlf bt,F
btfsc STATUS,C
goto outby1
call bit0
goto outby2
outby1 call bit1
outby2 decfsz count2,F
goto outby0
;
call bit1
; and bit0

bit0 movlw pr2_value-3
movwf TMR2

movlw ccp1con_value ; HIGH
movwf CCP1CON

ndelaya0 movf mtx_delay, W
movwf ncnt
ndelaya1 decfsz ncnt, F
goto ndelaya1

movlw 0 ; to LOW transition
movwf CCP1CON

ndelayb0 movf mtx_delay, W
movwf ncnt
ndelayb1 decfsz ncnt, F
goto ndelayb1

return

bit1 movlw 0 ; LOW
movwf CCP1CON

ndelayc0 movf mtx_delay, W
movwf ncnt
ndelayc1 decfsz ncnt, F
goto ndelayc1

movlw pr2_value-3
movwf TMR2
movlw ccp1con_value ; to HIGH transition
movwf CCP1CON

ndelaye0 movf mtx_delay, W
movwf ncnt
ndelaye1 decfsz ncnt, F
goto ndelaye1

return

end
SOTASOTA
- 5th June 2014, 15:04
The next step once this is figured out will see how I can use Pic Basic 3 to compile and make a HEX file so I can program the pic. I tried to compile already but got lots of errors. But, will cross that bridge later.... :-)
SOTASOTA
- 5th June 2014, 15:07
Also SORRY for the multiple posts. I could not figure out how to delete the other post. Can you let me know how I delete posts? Thanks and my apologies. :-)
Demon
- 5th June 2014, 18:18
Don't worry about double thread, it's closed and you didn't get any infraction. I just posted a "canned reply" that we have available.

Post all your code using code tags in Advanced at bottom right. Also mention which PIC and assembler.

Robert


Edit: oh yeah, and the errors!
SOTASOTA
- 6th June 2014, 03:09
Thanks Robert! I still do not know how to delete a thread. :-)

OK, as for the code, at this stage I need to figure out why a key-press only allows for a 1-2 second burst rather than continuous. Then, once that is figured out, I will then try to compile it. I am using PBP3 and EPIC USB programmer. Thanks!
Archangel
- 6th June 2014, 09:35
The next step once this is figured out will see how I can use Pic Basic 3 to compile and make a HEX file so I can program the pic. I tried to compile already but got lots of errors. But, will cross that bridge later.... :-)That is the job of MPASM. PBP accepts BASIC Mnemonics and creates the Assembly code, mpasm turns the assembly code into the intel hex, which you load into the PIC with your programmer. When you have set up MicroCode Studio correctly it becomes a 1 click operation, unless you have an error in your code or inadvertently choose the wrong PIC.