Select case function

Hello everyone,

I'm looking for some tips, to enhance the code listed here to simplify with less code the "Select case'.

This code is for a PIC18F25K22 using PortC as a 64 switches matrix scan and PortB as the receiver and decoder and PortA to send the data.

Thanks for any comments.

Code:

---

' PIC18F25K22 64 Keys Encoder
' File :"D:\PIC\PBP3\18F25K22\64 Keys Encoder\64 Keys Encoder.pbp"
' Date : Feb 13 2025
'
' WPUB : p152 PORTB only
' PORTA : Flags
' PORTB : Row Input
' PORTC : Column Out
;----[18F25K22 Hardware Configuration]------------------------------------------
#CONFIG
  CONFIG  FOSC = INTIO67    ; Internal oscillator block
  CONFIG  PLLCFG = ON        ; Oscillator used directly
  CONFIG  PRICLKEN = OFF    ; Primary clock can be disabled by software
  CONFIG  FCMEN = OFF        ; Fail-Safe Clock Monitor disabled
  CONFIG  IESO = OFF        ; Oscillator Switchover mode disabled
  CONFIG  PWRTEN = OFF      ; Power up timer disabled
  CONFIG  BOREN = SBORDIS    ; Brown-out Reset enabled in hardware only (SBOREN is disabled)
  CONFIG  BORV = 190        ; VBOR set to 1.90 V nominal
  CONFIG  WDTEN = ON        ; WDT is always enabled. SWDTEN bit has no effect
  CONFIG  WDTPS = 32768      ; 1:32768
  CONFIG  CCP2MX = PORTC1    ; CCP2 input/output is multiplexed with RC1
  CONFIG  PBADEN = OFF      ; PORTB<5:0> pins are configured as digital I/O on Reset
  CONFIG  CCP3MX = PORTB5    ; P3A/CCP3 input/output is multiplexed with RB5
  CONFIG  HFOFST = ON        ; HFINTOSC output and ready status are not delayed by the oscillator stable status
  CONFIG  T3CMX = PORTC0    ; T3CKI is on RC0
  CONFIG  P2BMX = PORTB5    ; P2B is on RB5
  CONFIG  MCLRE = INTMCLR    ; MCLR pin enabled, RE3 input pin disabled
  CONFIG  STVREN = ON        ; Stack full/underflow will cause Reset
  CONFIG  LVP = OFF          ; Single-Supply ICSP disabled
  CONFIG  XINST = OFF        ; Instruction set extension and Indexed Addressing mode disabled (Legacy mode)
  CONFIG  DEBUG = OFF        ; Disabled
  CONFIG  CP0 = OFF          ; Block 0 (000800-001FFFh) not code-protected
  CONFIG  CP1 = OFF          ; Block 1 (002000-003FFFh) not code-protected
  CONFIG  CP2 = OFF          ; Block 2 (004000-005FFFh) not code-protected
  CONFIG  CP3 = OFF          ; Block 3 (006000-007FFFh) not code-protected
  CONFIG  CPB = OFF          ; Boot block (000000-0007FFh) not code-protected
  CONFIG  CPD = OFF          ; Data EEPROM not code-protected
  CONFIG  WRT0 = OFF        ; Block 0 (000800-001FFFh) not write-protected
  CONFIG  WRT1 = OFF        ; Block 1 (002000-003FFFh) not write-protected
  CONFIG  WRT2 = OFF        ; Block 2 (004000-005FFFh) not write-protected
  CONFIG  WRT3 = OFF        ; Block 3 (006000-007FFFh) not write-protected
  CONFIG  WRTC = OFF        ; Configuration registers (300000-3000FFh) not write-protected
  CONFIG  WRTB = OFF        ; Boot Block (000000-0007FFh) not write-protected
  CONFIG  WRTD = OFF        ; Data EEPROM not write-protected
  CONFIG  EBTR0 = OFF        ; Block 0 (000800-001FFFh) not protected from table reads executed in other blocks
  CONFIG  EBTR1 = OFF        ; Block 1 (002000-003FFFh) not protected from table reads executed in other blocks
  CONFIG  EBTR2 = OFF        ; Block 2 (004000-005FFFh) not protected from table reads executed in other blocks
  CONFIG  EBTR3 = OFF        ; Block 3 (006000-007FFFh) not protected from table reads executed in other blocks
  CONFIG  EBTRB = OFF        ; Boot Block (000000-0007FFh) not protected from table reads executed in other blocks
#ENDCONFIG


define OSC 64                ' OSC 64Mhz
ANSELA = 0                  ' Set all digital
ANSELB = 0                  ' Set all digital
ANSELC = 0                  ' Set all digital
WPUB = $FF                  ' Set Weak PullUP PORTB only


'CMCON0 = 7
TRISA = 000000            ' PORTA Key Output 
TRISB = 111111            ' PORTB Intput Keypad Rows in           
TRISC = 000000            ' PORTC Output Keypad Column out
TRISE = 001000            ' PORTE.3 MCLRE as input '1' other output '0'
OSCCON = $70                ' Internal OSC p:30
OSCTUNE = $40                ' for 64Mhz FOSC p:35


Latch1 var byte              ' Latch1 Flag
Latch1 = 0


LRShift VAR BIT              ' Shift Direction Flag
LRSHIFT = 0


TTL VAR WORD                  'Key val
TTL = 0


TTLadd var word              ' adding to PORTC val
ttladd = 0


PORTKey var byte            ' Key data
portkey = 0


Baud var word                ' Serout2 Baud Rate
Baud = 84
'Baud =  16468


PORTB = 0                    ' PORTB set to 0 Keypad Row
PAUSE 10
PORTC = 000001            ' Keypad Column out to Row PORTB
PORTA.0 = 1                  ' serial port = 1 'avoid random data'
PORTA.1 = 0                  ' Data Available


MAIN:                        ' Main Routine


PAUSE 1                    ' needed for PORTC > PORTB Data transfert
LATB = PORTB                ' Needed to use the value of PORTB


' Output Data to PORTC
IF PORTB > 0 AND Latch1 = 0 THEN
    Latch1 = 1
    LATC = LATB
    PAUSE 5   


' prevent duplicate
IF PORTC = 1 THEN
    TTLADD = 0
endif
IF PORTC = 2 THEN
    TTLADD = 128
endif
IF PORTC = 4 THEN
    TTLADD = 384
endif
IF PORTC = 8 THEN
    TTLADD = 512
endif
IF PORTC = 16 THEN
    TTLADD = 640
endif
IF PORTC = 32 THEN
    TTLADD = 758
endif
IF PORTC = 64 THEN
    TTLADD = 896
endif
IF PORTC = 128 THEN
    TTLADD = 1024
endif
' prevent duplicate


TTL = TTLADD + PORTB


' Select PORTKkey val
Select Case ttl
    case 1
    portkey = 1 : goto P
    case 2
    portkey = 2 : goto P
    case 4
    portkey = 3 : goto P
    case 8
    portkey = 4 : goto P
    case 16
    portkey = 5 : goto P
    case 32
    portkey = 6 : goto P
    case 64
    portkey = 7 : goto P
    case 128
    portkey = 8 : goto P


    case 129
    portkey = 9 : goto P
    case 130
    portkey = 10 : goto P
    case 132
    portkey = 11 : goto P
    case 136
    portkey = 12 : goto P
    case 144
    portkey = 13 : goto P
    case 160
    portkey = 14 : goto P
    case 192
    portkey = 15 : goto P
    case 256
    portkey = 16 : goto P


    case 385
    portkey = 17 : goto P
    case 386
    portkey = 18 : goto P
    case 388
    portkey = 19 : goto P
    case 392
    portkey = 20 : goto P
    case 400
    portkey = 21 : goto P
    case 416
    portkey = 22 : goto P
    case 448
    portkey = 23 : goto P
    case 512
    portkey = 24 : goto P


    case 513
    portkey = 25 : goto P
    case 514
    portkey = 26 : goto P
    case 516
    portkey = 27 : goto P
    case 520
    portkey = 28 : goto P
    case 528
    portkey = 29 : goto P
    case 544
    portkey = 30 : goto P
    case 576
    portkey = 31 : goto P
    case 640
    portkey = 32 : goto P


    case 641
    portkey = 33 : goto P
    case 642
    portkey = 34 : goto P
    case 644
    portkey = 35: goto P
    case 648
    portkey = 36 : goto P
    case 656
    portkey = 37 : goto P
    case 672
    portkey = 38 : goto P
    case 704
    portkey = 39 : goto P
    case 768
    portkey = 40 : goto P


    case 759
    portkey = 41 : goto P
    case 760
    portkey = 42 : goto P
    case 762
    portkey = 43 : goto P
    case 766
    portkey = 44 : goto P
    case 774
    portkey = 45 : goto P
    case 790
    portkey = 46 : goto P
    case 822
    portkey = 47 : goto P
    case 886
    portkey = 48 : goto P


    case 897
    portkey = 49 : goto P
    case 898
    portkey = 50 : goto P
    case 900
    portkey = 51 : goto P
    case 904
    portkey = 52 : goto P
    case 912
    portkey = 53 : goto P
    case 928
    portkey = 54 : goto P
    case 960
    portkey = 55 : goto P
    case 1024
    portkey = 56 : goto P


    case 1025
    portkey = 57 : goto P
    case 1026
    portkey = 58 : goto P
    case 1028
    portkey = 59 : goto P
    case 1032
    portkey = 60 : goto P
    case 1040
    portkey = 61 : goto P
    case 1056
    portkey = 62 : goto P
    case 1088
    portkey = 63 : goto P
    case 1152
    portkey = 64 : goto P
end select
' Select PORTKkey val


P:
pause 10
PORTA.1 = 1  ' Data Available


'SEROUT2 PORTA.0,Baud,[dec3 LATC," PORTC Bin: ", bin8 LATC,13,10]  ' SW PORTC Column to PORTB Row
'SEROUT2 PORTA.0,Baud,[dec3 LATB," PORTB Bin: ", bin8 LATB," DEC TTL : ",DEC5 TTL," BIN TTL: ",BIN16 TTL,13,10]  '  SW PORTB Row from PORTC Column
sEROUT2 PORTA.0,Baud,[" PORTB Dec :",dec3 LATB," PORTB Bin: ", bin8 LATB," TTL Dec : ",DEC4 TTL," TTL Bin : ",BIN16 TTL," Port Key: ",dec2 portkey," Port Key Bin : ",bin8 portkey,13,10] 


ENDIF


' Wait for Key Release
WHILE PORTB > 0
WEND


' Reset Flag
latch1 = 0                  ' Latch1
PORTA.1 = 0                  ' Data Available
LATC = 0                    ' LATC
TTL = 0
pause 50                    ' Debounce pause


' Shift Direction Flag
IF PORTC = 1 THEN
    lrshift = 0
endif
IF PORTC = 128 THEN
    lrshift = 1
endif


' Shift PORTC
if lrshift = 0 then
    PORTC = PORTC << 1      ' Shift Left
endif
if lrshift = 1 then
    PORTC = PORTC >> 1      ' Shift Right
ENDIF


goto main                    ' restart loop

---

Attachment 0
Attachment 9907

Attachment 0
Attachment 9908

just need to keep ONE GoTo P @ the end of your Select case's after the End Select

your syntax is " not so good " :rolleyes:

Code:

---


' prevent duplicate

IF PORTC = 1 THEN
    TTLADD = 0
endif

IF PORTC = 2 THEN
  TTLADD = 128
endif

IF PORTC = 4 THEN
  TTLADD = 384
endif


---

One more good reason to use " select case " ...

I think you should read carefully the select case page of your Holy Manual ... ( not a C Compiler manual ... )

does the Select function case has to read every case before end select , or it's getting out when found the right one

the Goto P it's there so when a case is match then Goto P, to avoid reading all the case

Quote:

---

Originally Posted by jackberg1

does the Select function case has to read every case before end select , or it's getting out when found the right one

the Goto P it's there so when a case is match then Goto P, to avoid reading all the case

---

I think you should read carefully the select case page of your Holy Manual

for a 8x8 keypad there are 64 possible results
that's an extraordinary convoluted way to get a result


why not

Code:

---

key var byte    ; high nibble column  low nibble row
  if portb then    'look for a 1
      key = ncd portb  'row    look for a 1
      key = key + (ncd portc )<<4
      PORTA.1 = 1  ' Data Available
      WHILE PORTB >0 :wend
  endif

---

Thank you richard

the reason I had to add a value to the portc, was the fact in the 64 key matrix some code were duplicate.
so 2 different key had the same value.

I'll have to test this code.

Attachment 9909

Hello Richard

by inverting portb / portc I found no duplicate

If I may ask, how to know the time it took from the start to end of a for/next loop or select case in a program


Many thanks for your support.

Code:

---


      key = ncd portb  'row    look for a 1
      key = key + (ncd portc )<<4

---

Quote:

---

If I may ask, how to know the time it took from the start to end of a for/next loop or select case in a program

---

Depends on what's available. I usually just set a pin high at the start and low again at the end of the routine I want to measure and then look at the pin using a scope or logic analyzer. Another option is to use one of the hardware timers and send the result to the PC using whatever serial connection is available (DEBUG, SEROUT, HSEROUT) but for longer routines one has to be little bit careful as to not overflow the timer and therefor get misleading values.

/Henrik.

Thank you HenrikOlsson

This is a very usefull solution since I got on hand a logic analyzer + scope.

Hello HenrikOlsson,

I did some timing test for the 'Select case' for key # 1 ~ key # 64

case # 1 : 3.48us and the last of the case key # 64 : 134.9us

Thanks again for this clever trick.

Quote:

---

If I may ask, how to know the time it took from the start to end of a for/next loop or select case in a program

---

the PBP soft way : https://dt.picbasic.co.uk/CODEX/CodeTimer

Hello Richard,

I rewrote my keypad program with the NCD function that you recomended, that help a lot

I changed the column value to the range from 1 ~ 64 with this I'm able to get an

average of 10~12us for the data available output signal.

The project served as a replacement of the old MM74C922/3.

Thanks again Richard for your great help.

Code:

---


' PIC18F25K22 64 Keys Encoder
' File      : "D:\PIC\PBP3\18F25K22\64 Keys Encoder\64 Keys Encoder V2.pbp"
' Date      : Feb 16 2025
' Benchmark : PortKey 1~64:~12us
' Used      : 543 bytes
' WPUB      : p152 PORTB only
' PORTA    : Data Available D/A PORTA.7:High
' PORTB    : Row Input
' PORTC    : Column Output
'----[18F25K22 Hardware Configuration]------------------------------------------
#CONFIG
  CONFIG  FOSC = INTIO67    ; Internal oscillator block
  CONFIG  PLLCFG = ON        ; Oscillator multiplied by 4
  CONFIG  PRICLKEN = OFF    ; Primary clock can be disabled by software
  CONFIG  FCMEN = OFF        ; Fail-Safe Clock Monitor disabled
  CONFIG  IESO = OFF        ; Oscillator Switchover mode disabled
  CONFIG  PWRTEN = OFF      ; Power up timer disabled
  CONFIG  BOREN = SBORDIS    ; Brown-out Reset enabled in hardware only (SBOREN is disabled)
  CONFIG  BORV = 190        ; VBOR set to 1.90 V nominal
  CONFIG  WDTEN = OFF        ; Watch dog timer is always disabled. SWDTEN has no effect.
  CONFIG  WDTPS = 32768      ; 1:32768
  CONFIG  CCP2MX = PORTC1    ; CCP2 input/output is multiplexed with RC1
  CONFIG  PBADEN = OFF      ; PORTB<5:0> pins are configured as digital I/O on Reset
  CONFIG  CCP3MX = PORTB5    ; P3A/CCP3 input/output is multiplexed with RB5
  CONFIG  HFOFST = ON        ; HFINTOSC output and ready status are not delayed by the oscillator stable status
  CONFIG  T3CMX = PORTC0    ; T3CKI is on RC0
  CONFIG  P2BMX = PORTB5    ; P2B is on RB5
  CONFIG  MCLRE = INTMCLR    ; RE3 input pin enabled; MCLR disabled
  CONFIG  STVREN = ON        ; Stack full/underflow will cause Reset
  CONFIG  LVP = OFF          ; Single-Supply ICSP disabled
#ENDCONFIG


define OSC 64                ' OSC 64Mhz
ANSELA = 0                  ' Set all digital
ANSELB = 0                  ' Set all digital
ANSELC = 0                  ' Set all digital
'WPUB = $FF                  ' Set Weak PullUP PORTB only
'CMCON0 = 7
TRISA = 000000            ' PORTA Key Data available output 
TRISB = 111111            ' PORTB Intput Keypad Rows in           
TRISC = 000000            ' PORTC Output Keypad Column out
TRISE = 001000            ' PORTE.3 MCLRE as input '1' other output '0'
OSCCON = $70                ' Internal OSC p:30
OSCTUNE = $40                ' for 64Mhz FOSC p:35


' Var for Key & Port
Latch1 var byte              ' Latch1 Flag
Latch1 = 0
LRShift VAR BIT              ' Shift Direction Flag
LRSHIFT = 0


NCDB VAR BYTE                ' NCD PORTB
NCDC VAR BYTE                ' NCD PORTC


PORTKey var byte            ' Key# data
portkey = 0


' Serial Terminal
Baud var word                ' Serout2 Baud Rate
Baud = 84
'Baud =  16468


PAUSE 100
PORTC = 000001            ' Keypad Column out to Row PORTB
PORTA.7 = 0                  ' Data Available
PORTB = 000000            ' PORTB set to 0 Keypad Row


MAIN:                        ' Main Routine


' Output Data to PORTC
IF PORTB > 0 AND Latch1 = 0 THEN
    Latch1 = 1
    'PORTA.1 = 1            ' Benchmark


    ' Get bit position 1~8
    NCDB = NCD PORTB        ' PORTB Row 'in'
    NCDC = NCD PORTC        ' PORTC Column 'out'


    ' Assign new value for PORTC Column
    SELECT CASE NCDC
        CASE 1
        NCDC = 0
        CASE 2
        NCDC = 8
        CASE 3
        NCDC = 16
        CASE 4
        NCDC = 24
        CASE 5
        NCDC = 32
        CASE 6
        NCDC = 40
        CASE 7
        NCDC = 48
        CASE 8
        NCDC = 56
    END SELECT

    PORTKey = NCDC + NCDB    ' Key# Data 1~64
    PORTA = PORTKEY          ' Data output
    pause 1                  ' Mandatory pause > 0  for PORTA to set
    PORTA.7 = 1              ' Data available
    'sEROUT2 PORTA.0,Baud,[" PORTB NCD: ",dec1 NCDB," PORTC NCD:",DEC1 NCDC," PORTKey :",DEC2 PORTKey,13,10] 
ENDIF


' Wait for Key Release
WHILE PORTB > 0
WEND
pause 5                      ' Key release debounce


' Reset Flag
latch1 = 0                  ' Latch1
PORTA.7 = 0                  ' Data available
PORTA.1 = 0                  ' Benchmark
PORTKey = 0


' Shift Direction Flag
IF PORTC = 1 THEN
    lrshift = 0
endif
IF PORTC = 128 THEN
    lrshift = 1
endif


' Shift PORTC
if lrshift = 0 then
    PORTC = PORTC << 1      ' Shift Left
endif
if lrshift = 1 then
    PORTC = PORTC >> 1      ' Shift Right
ENDIF
PAUSE 1                      ' Mandatory pause > 0  wait for Shift to set
goto main                    ' restart loop

---

With these errors, I think it cannot work...

Have marked with red the errors.

You should use percent character followed by binary values.

Ioannis

Code:

---


' PIC18F25K22 64 Keys Encoder
' File      : "D:\PIC\PBP3\18F25K22\64 Keys Encoder\64 Keys Encoder V2.pbp"
' Date      : Feb 16 2025
' Benchmark : PortKey 1~64:~12us
' Used      : 543 bytes
' WPUB      : p152 PORTB only
' PORTA    : Data Available D/A PORTA.7:High
' PORTB    : Row Input
' PORTC    : Column Output
'----[18F25K22 Hardware Configuration]------------------------------------------
#CONFIG
  CONFIG  FOSC = INTIO67    ; Internal oscillator block
  CONFIG  PLLCFG = ON        ; Oscillator multiplied by 4
  CONFIG  PRICLKEN = OFF    ; Primary clock can be disabled by software
  CONFIG  FCMEN = OFF        ; Fail-Safe Clock Monitor disabled
  CONFIG  IESO = OFF        ; Oscillator Switchover mode disabled
  CONFIG  PWRTEN = OFF      ; Power up timer disabled
  CONFIG  BOREN = SBORDIS    ; Brown-out Reset enabled in hardware only (SBOREN is disabled)
  CONFIG  BORV = 190        ; VBOR set to 1.90 V nominal
  CONFIG  WDTEN = OFF        ; Watch dog timer is always disabled. SWDTEN has no effect.
  CONFIG  WDTPS = 32768      ; 1:32768
  CONFIG  CCP2MX = PORTC1    ; CCP2 input/output is multiplexed with RC1
  CONFIG  PBADEN = OFF      ; PORTB<5:0> pins are configured as digital I/O on Reset
  CONFIG  CCP3MX = PORTB5    ; P3A/CCP3 input/output is multiplexed with RB5
  CONFIG  HFOFST = ON        ; HFINTOSC output and ready status are not delayed by the oscillator stable status
  CONFIG  T3CMX = PORTC0    ; T3CKI is on RC0
  CONFIG  P2BMX = PORTB5    ; P2B is on RB5
  CONFIG  MCLRE = INTMCLR    ; RE3 input pin enabled; MCLR disabled
  CONFIG  STVREN = ON        ; Stack full/underflow will cause Reset
  CONFIG  LVP = OFF          ; Single-Supply ICSP disabled
#ENDCONFIG


define OSC 64                ' OSC 64Mhz
ANSELA = 0                  ' Set all digital
ANSELB = 0                  ' Set all digital
ANSELC = 0                  ' Set all digital
'WPUB = $FF                  ' Set Weak PullUP PORTB only
'CMCON0 = 7
TRISA = 000000            ' PORTA Key Data available output 
TRISB = 111111            ' PORTB Intput Keypad Rows in           
TRISC = 000000            ' PORTC Output Keypad Column out
TRISE = 001000            ' PORTE.3 MCLRE as input '1' other output '0'
OSCCON = $70                ' Internal OSC p:30
OSCTUNE = $40                ' for 64Mhz FOSC p:35


' Var for Key & Port
Latch1 var byte              ' Latch1 Flag
Latch1 = 0
LRShift VAR BIT              ' Shift Direction Flag
LRSHIFT = 0


NCDB VAR BYTE                ' NCD PORTB
NCDC VAR BYTE                ' NCD PORTC


PORTKey var byte            ' Key# data
portkey = 0


' Serial Terminal
Baud var word                ' Serout2 Baud Rate
Baud = 84
'Baud =  16468


PAUSE 100
PORTC = 000001            ' Keypad Column out to Row PORTB
PORTA.7 = 0                  ' Data Available
PORTB = 000000            ' PORTB set to 0 Keypad Row


MAIN:                        ' Main Routine


' Output Data to PORTC
IF PORTB > 0 AND Latch1 = 0 THEN
    Latch1 = 1
    'PORTA.1 = 1            ' Benchmark


    ' Get bit position 1~8
    NCDB = NCD PORTB        ' PORTB Row 'in'
    NCDC = NCD PORTC        ' PORTC Column 'out'


    ' Assign new value for PORTC Column
    SELECT CASE NCDC
        CASE 1
        NCDC = 0
        CASE 2
        NCDC = 8
        CASE 3
        NCDC = 16
        CASE 4
        NCDC = 24
        CASE 5
        NCDC = 32
        CASE 6
        NCDC = 40
        CASE 7
        NCDC = 48
        CASE 8
        NCDC = 56
    END SELECT

    PORTKey = NCDC + NCDB    ' Key# Data 1~64
    PORTA = PORTKEY          ' Data output
    pause 1                  ' Mandatory pause > 0  for PORTA to set
    PORTA.7 = 1              ' Data available
    'sEROUT2 PORTA.0,Baud,[" PORTB NCD: ",dec1 NCDB," PORTC NCD:",DEC1 NCDC," PORTKey :",DEC2 PORTKey,13,10] 
ENDIF


' Wait for Key Release
WHILE PORTB > 0
WEND
pause 5                      ' Key release debounce


' Reset Flag
latch1 = 0                  ' Latch1
PORTA.7 = 0                  ' Data available
PORTA.1 = 0                  ' Benchmark
PORTKey = 0


' Shift Direction Flag
IF PORTC = 1 THEN
    lrshift = 0
endif
IF PORTC = 128 THEN
    lrshift = 1
endif


' Shift PORTC
if lrshift = 0 then
    PORTC = PORTC << 1      ' Shift Left
endif
if lrshift = 1 then
    PORTC = PORTC >> 1      ' Shift Right
ENDIF
PAUSE 1                      ' Mandatory pause > 0  wait for Shift to set
goto main                    ' restart loop

---

Thanks Ioannis for pointing this, the % are in fact on my program.
when uploading to the site something I select 'Courrier New' font append, and it's look they just vannish.
here's the upload.

'2nd upload seem to work fine this time'

Code:

---


' PIC18F25K22 64 Keys Encoder
' File      : "D:\PIC\PBP3\18F25K22\64 Keys Encoder\64 Keys Encoder V2.pbp"
' Date      : Feb 16 2025
' Benchmark : PortKey 1~64:~12us
' Used      : 543 bytes
' WPUB      : p152 PORTB only
' PORTA    : Data Available D/A PORTA.7:High
' PORTB    : Row Input
' PORTC    : Column Output
'----[18F25K22 Hardware Configuration]------------------------------------------
#CONFIG
  CONFIG  FOSC = INTIO67    ; Internal oscillator block
  CONFIG  PLLCFG = ON        ; Oscillator multiplied by 4
  CONFIG  PRICLKEN = OFF    ; Primary clock can be disabled by software
  CONFIG  FCMEN = OFF        ; Fail-Safe Clock Monitor disabled
  CONFIG  IESO = OFF        ; Oscillator Switchover mode disabled
  CONFIG  PWRTEN = OFF      ; Power up timer disabled
  CONFIG  BOREN = SBORDIS    ; Brown-out Reset enabled in hardware only (SBOREN is disabled)
  CONFIG  BORV = 190        ; VBOR set to 1.90 V nominal
  CONFIG  WDTEN = OFF        ; Watch dog timer is always disabled. SWDTEN has no effect.
  CONFIG  WDTPS = 32768      ; 1:32768
  CONFIG  CCP2MX = PORTC1    ; CCP2 input/output is multiplexed with RC1
  CONFIG  PBADEN = OFF      ; PORTB<5:0> pins are configured as digital I/O on Reset
  CONFIG  CCP3MX = PORTB5    ; P3A/CCP3 input/output is multiplexed with RB5
  CONFIG  HFOFST = ON        ; HFINTOSC output and ready status are not delayed by the oscillator stable status
  CONFIG  T3CMX = PORTC0    ; T3CKI is on RC0
  CONFIG  P2BMX = PORTB5    ; P2B is on RB5
  CONFIG  MCLRE = INTMCLR    ; RE3 input pin enabled; MCLR disabled
  CONFIG  STVREN = ON        ; Stack full/underflow will cause Reset
  CONFIG  LVP = OFF          ; Single-Supply ICSP disabled
#ENDCONFIG


define OSC 64                ' OSC 64Mhz
ANSELA = 0                  ' Set all digital
ANSELB = 0                  ' Set all digital
ANSELC = 0                  ' Set all digital
'WPUB = $FF                  ' Set Weak PullUP PORTB only
'CMCON0 = 7
TRISA = %00000000            ' PORTA Key Data available output 
TRISB = %11111111            ' PORTB Intput Keypad Rows in           
TRISC = %00000000            ' PORTC Output Keypad Column out
TRISE = %00001000            ' PORTE.3 MCLRE as input '1' other output '0'
OSCCON = $70                ' Internal OSC p:30
OSCTUNE = $40                ' for 64Mhz FOSC p:35


' Var for Key & Port
Latch1 var byte              ' Latch1 Flag
Latch1 = 0
LRShift VAR BIT              ' Shift Direction Flag
LRSHIFT = 0


NCDB VAR BYTE                ' NCD PORTB
NCDC VAR BYTE                ' NCD PORTC


PORTKey var byte            ' Key# data
portkey = 0


' Serial Terminal
Baud var word                ' Serout2 Baud Rate
Baud = 84
PORTA.0 = 1                  ' Avoid garbage on serial


PAUSE 100
PORTC = %00000001            ' Keypad Column out to Row PORTB
PORTA.7 = 0                  ' Data Available
PORTB = %00000000            ' PORTB set to 0 Keypad Row


MAIN:                        ' Main Routine


' Output Data to PORTC
IF PORTB > 0 AND Latch1 = 0 THEN
    Latch1 = 1

    'PORTA.1 = 1            ' Benchmark


    ' Get bit position 1~8
    NCDB = NCD PORTB        ' PORTB Row 'in'
    NCDC = NCD PORTC        ' PORTC Column 'out'


    ' Assign new value for PORTC Column
    SELECT CASE NCDC
        CASE 1
        NCDC = 0
        CASE 8
        NCDC = 56
        CASE 2
        NCDC = 8
        CASE 7
        NCDC = 48
        CASE 3
        NCDC = 16
        CASE 6
        NCDC = 40
        CASE 4
        NCDC = 24
        CASE 5
        NCDC = 32
    END SELECT



    PORTKey = NCDC + NCDB    ' Key# Data 1~64
    'PORTA = PORTKEY          ' Data output


  'PORTA.1 = 0              ' Benchmark 


    pause 2                  ' Mandatory pause > 0  for PORTA to set

    PORTA.7 = 1              ' Data available
    sEROUT2 PORTA.0,Baud,[" PORTB NCD: ",dec1 NCDB," PORTC NCD:",DEC1 NCDC," PORTKey :",DEC2 PORTKey,13,10] 
ENDIF


' Wait for Key Release
WHILE PORTB > 0
WEND
pause 5                      ' Key release debounce


' Reset Flag
latch1 = 0                  ' Latch1
PORTA.7 = 0                  ' Data available
PORTKey = 0


' Shift Direction Flag
IF PORTC = 1 THEN
    lrshift = 0
endif
IF PORTC = 128 THEN
    lrshift = 1
endif



' Shift PORTC
if lrshift = 0 then
    PORTC = PORTC << 1      ' Shift Left
endif
if lrshift = 1 then
    PORTC = PORTC >> 1      ' Shift Right
ENDIF


PAUSE 1                      ' Mandatory pause > 0  wait for Shift to set
goto main                    ' restart loop

---

This is the lasted update, some changes the 'Select case' as been move down

this alone is reducing the response time from 11us to 6us to the data available.

While the propagation time at the D/A of the MM74C922 is 60ns ~ 150ns max.

It will be hard to even get close to 500ns with the PIC18F25K22 unless someone has an idea to share.

I searched the internet for an affordable / alternative solution is to get into the CPLD or FPGA but it's not cost effective + VHDL learning process.

Any constructive comments is welcome.


Attachment 9911

Here's the updated code (when using the '#" Wrap code, if I edit my post and save it, after the '%' or other characters are remove from the listing)

' PIC18F25K22 64 Keys Encoder V3
' File : "D:\PIC\PBP3\18F25K22\64 Keys Encoder\64 Keys Encoder V3.pbp"
' Date : Feb 19 2025
' Benchmark : PortKey 1~64: 3.988us ~ 6.25us
' Used : 621 bytes
' WPUB : p152 PORTB only
' PORTA : Data Available D/A PORTA.7:High
' PORTB : Row Input
' PORTC : Column Output
'----[18F25K22 Hardware Configuration]------------------------------------------
#CONFIG
CONFIG FOSC = INTIO67 ; Internal oscillator block
CONFIG PLLCFG = ON ; Oscillator multiplied by 4
CONFIG PRICLKEN = OFF ; Primary clock can be disabled by software
CONFIG FCMEN = OFF ; Fail-Safe Clock Monitor disabled
CONFIG IESO = OFF ; Oscillator Switchover mode disabled
CONFIG PWRTEN = OFF ; Power up timer disabled
CONFIG BOREN = SBORDIS ; Brown-out Reset enabled in hardware only (SBOREN is disabled)
CONFIG BORV = 190 ; VBOR set to 1.90 V nominal
CONFIG WDTEN = OFF ; Watch dog timer is always disabled. SWDTEN has no effect.
CONFIG WDTPS = 32768 ; 1:32768
CONFIG CCP2MX = PORTC1 ; CCP2 input/output is multiplexed with RC1
CONFIG PBADEN = OFF ; PORTB<5:0> pins are configured as digital I/O on Reset
CONFIG CCP3MX = PORTB5 ; P3A/CCP3 input/output is multiplexed with RB5
CONFIG HFOFST = ON ; HFINTOSC output and ready status are not delayed by the oscillator stable status
CONFIG T3CMX = PORTC0 ; T3CKI is on RC0
CONFIG P2BMX = PORTB5 ; P2B is on RB5
CONFIG MCLRE = INTMCLR ; RE3 input pin enabled; MCLR disabled
CONFIG STVREN = ON ; Stack full/underflow will cause Reset
CONFIG LVP = OFF ; Single-Supply ICSP disabled
#ENDCONFIG


define OSC 64 ' OSC 64Mhz
ANSELA = 0 ' Set all digital
ANSELB = 0 ' Set all digital
ANSELC = 0 ' Set all digital
'WPUB = $FF ' Set Weak PullUP PORTB only
'CMCON0 = 7
TRISA = %00000000 ' PORTA Key Data available output
TRISB = %11111111 ' PORTB Intput Keypad Rows in
TRISC = %00000000 ' PORTC Output Keypad Column out
TRISE = %00001000 ' PORTE.3 MCLRE as input '1' other output '0'
OSCCON = $70 ' Internal OSC p:30
OSCTUNE = $40 ' for 64Mhz FOSC p:35


' Var for Key & Port
Latch1 var byte ' Latch1 Flag
Latch1 = 0
LRShift VAR BIT ' Shift Direction Flag
LRSHIFT = 0


NCDC VAR BYTE ' PORTC Bit Position 1~8
PORTKey var byte ' Key# data
portkey = 0


Baud var word ' Serout2 Baud Rate
Baud = 84


PORTA.0 = 1 ' Avoid random char on serial


PAUSE 100
PORTC = %00000001 ' Keypad Scan Column out to PORTB
PORTA.7 = 0 ' Data available / Benchmark
PORTB = %00000000 ' PORTB Keypad Row


MAIN: ' Main Routine


IF PORTB > 0 AND Latch1 = 0 THEN ' Detect Press Switch and Latch
Latch1 = 1


' PORTA.7 = 1 ' Benchmark Start


PORTKey = NCDC + NCD PORTB ' add bit position 1~8
'PORTA = PORTKEY ' Set PORTA / Disable for SEROUT2


' PORTA.7 = 0 ' Benchmark End


PAUSE 5 ' pause before D/A PORTA.7
PORTA.7 = 1 ' Data available / Disable for Benchmark


SEROUT2 PORTA.0,Baud,[" PORTB NCD: ",dec1 NCD PORTB," PORTC NCD:",DEC1 NCD PORTC," D/A PORTKey :",DEC2 PORTKey,13,10]
ENDIF


' Wait for Key Release
WHILE PORTB > 0
WEND
pause 5 ' Key release debounce


' Reset Flag
latch1 = 0 ' Latch1
PORTA.7 = 0 ' Data available after Key release
PORTKey = 0


' Shift Direction Flag
IF PORTC = 1 THEN
lrshift = 0
endif
IF PORTC = 128 THEN
lrshift = 1
endif

' Shift PORTC
if lrshift = 0 then
PORTC = PORTC << 1 ' Shift Left
endif
if lrshift = 1 then
PORTC = PORTC >> 1 ' Shift Right
ENDIF
PAUSEUS 20 ' pauseus wait for Shift to set


SELECT CASE NCD PORTC ' Assign new value for PORTC Column
CASE 1
NCDC = 0
CASE 8
NCDC = 56
CASE 2
NCDC = 8
CASE 7
NCDC = 48
CASE 3
NCDC = 16
CASE 6
NCDC = 40
CASE 4
NCDC = 24
CASE 5
NCDC = 32
END SELECT


goto main ' restart loop

While trying to correct my previous listing the 'Administrator is preventing me to edit after 30 minutes'

Dear Administrator read my previous post about the characters missing or changes after uploading to your site.

thank you

\ (when using the '#" Wrap code, if I edit my post and save it, after the '%' or other characters are remove from the listing

even some characters are show in lower case instead of upper case)\