See more projects using micros:
Elektor,EPE,Silicon Chip

2 Digit Up/Down Counter with PIC12F628 and prototype PC board $25.00 plus $5.00 postage.
To order the kit, [send an email](mailto:colin@elechelp.com?Subject=Buying components for the 2 Digit Up/Down counter&Body=Please e-mail the cost of components for the 2 Digit Up/Down counter on prototype PC board for $25.00 plus postage by air mail to my country:****___**** and send details of how I can pay for it. My name is:____**)** to us and we will reply with the details of how to order etc.

• Page 1 2 digit Up/Down Counter using PIC16F628
• Page 2 adding Dice and Random Number (PIC16F628)
• P3 2 digit Up/Down Counter using PIC12F629
• Page 4 adding RF Link to PIC12F629 version
• Page 5 Car Gears Up/Down counter

Up/Down Counter using a PIC12F629

To take our programming skills further, we can use a PIC12F629 chip to produce a 2-Digit Up/Down Counter.
It might seem impossible to convert a project using an 18 pin chip to an 8-pin micro, but by using multiplexing skills and placing 2 buttons on the input-ONLY line of the chip, we can achieve this.
Most of the program sets up the drive-lines to access the segments. The actual part of the program that produces the “effect” is contained in the Main routine.
The PC board has two 7-segment displays made up of individual LEDs. Each segment consists of 2 LEDs in series. These are placed on an output line so that when the line is HIGH, one segment is illuminated, and when it is LOW, another segment is illuminated.
This allows the micro to illuminate 6 segments with 3 drive-lines.
The circuit is then made more complex by including a set of 4 transistors to select the left-hand or right-hand display.
This requires 2 more drive-lines.
The last line is an input-ONLY line and is used for the buttons.
Segment “g” is driven directly from the transistors in a similar way to an “H-bridge” where two diagonally opposite transistors turns on to produce a drive for the left-hand “g” segment and the other two diagonally opposite transistors turn on for the other “g” segment.
This project is merely a “conceptual” design to prove that noting is impossible in electronics.
PIC chips are less than 50 cents in large qualities and all the other components are less than 1 cent each.
This makes the project viable as the display is 50% larger and cheaper than using 7-segment displays.
The whole aim of the project is to learn programming and interfacing the micro to the outside world.

PIC12F629 2-Digit Counter

How the circuit works

There are a few interesting features in this circuit and they need some explaining.
The first is the illuminating of the LEDs. By connecting 2 LEDs in series and using a 5.5v supply, we can illuminate two LEDs for each segment.
The LEDs are connected to the positive rail via a transistor. This transistor is an NPN device and is acting as an emitter-follower so that when output GP0 or GP5 of the micro is HIGH, the emitter will deliver current to the LEDs via the collector-emitter circuit. The voltage at the emitter is 0.6v less than the base and the micro will rise to nearly rail voltage (about 0.3v below rail voltage), so the positive voltage is approx 6v - 0.6v - 0.6v - 0.3v = 4.5v
The cathode of the LED-pair is connected to one of the output lines GP1, GP2 or GP4 and the voltage on the line will be approx 0.3v. This will provide a supply voltage of approx 4.2v and illuminate the two LEDs. Each LED has a natural voltage drop of approx 1.9v so you can’t allow the battery voltage to drop very much before the display will fail to work. The 47R resistor limits the current though the LEDs.

When a drive-line GP1, GP2 or GP4 is taken HIGH, output GP0 or GP5 of the micro must be LOW to allow the other two LEDs will be illuminated.
To illuminate each segment, the input/output for each line must be allocated to the TRISIO register and each line must be allocated HIGH or LOW if it is an output. The combination of segments produces a digit on either the left display or right display and the instructions are contained in a separate sub-routine.
Once the sub-routine for each character (digit) has been worked out, the program from the previous project was pasted into the program and the only instructions needed changing were those that applied to the output port.
Two separate tables are needed; one for the left display and one for the right display.
The tables have a “goto” instruction at the beginning of each line so that the micro goes immediately to the sub-routine corresponding the chosen digit for either the left or right display. The sub-routine for each digit contains the “retlw” command, to send the micro back to the Main routine.
The project has been produced on Experimental board using surface-mount components with yellow LEDs for the display. It is not for beginners, however a kit of components is available from Talking Electronics for $15.00 plus $5.00 postage. The board must be adapted for the project and this requires cutting 10 of the tracks and fine enamelled wire to connect the components to the micro.

The PIC12F629 2-Digit Counter
Cut 10 tracks as shown in the layout below, so the board suits this project.

Layout for 2 Digit Up/Down Counter
Cut 10 tracks as shown in the layout above, so the board suits this project.

The files:

• 12F629Counter.asm
• 12F629Counter.hex
• 12F629Counter.txt
• 12F629Counter-h.txt
• Notepad++ or VS Code
• MPASM - this file comes on the CD with PICkit-2
• PICkit-2 - this “burning” or “programming program” on the CD with PICkit-2.

The program below is the assembly program. This is for viewing ONLY. To modify the program you will need to load this file: 12F629Counter.asm into NotePad2 and make the changes.
The .asm is then compiled via MPASM to produce a .hex file for PICkit-2.

Set up your desktop as follows, with a folder called PICkit-2 files. Inside this folder you can have other folders such as PIC12F629 Counter; then an icon for MPASM and an icon for PICkit-2:

 ;2Digit Counter   12F629.asm
    ;  13-6-2009

    list    p=12F629
    radix   dec
    include "p12f629.inc"

    errorlevel  -302  ;Dont complain about BANK 1 Reg during assembly

    __CONFIG    _MCLRE_OFF & _CP_OFF & _WDT_OFF
            & _INTRC_OSC_NOCLKOUT  ;Internal osc.


temp1       equ     20h ;
temp2       equ     21h ;
temp3       equ     22h ;
SwUp        equ 23h ;
SwDwn       equ 24h ;
units       equ 25h ;
tens        equ 26h ;
Sw_Flag     equ 27h ;
FastCount   equ 28h ;
Count       equ 29h ; counting 00 to 99
File5mS     equ     2Ah     ;
FileXmS     equ     2Bh     ;

;****************************************************************
;Equates
;****************************************************************
status      equ 0x03
rp1     equ 0x06
rp0     equ 0x05
portA       equ     0x05
portB       equ     0x06

status      equ 03h
option_reg  equ     81h

        ; bits on GPIO

pin7    equ 0   ;GP0
pin6    equ 1   ;GP1
pin5    equ 2   ;GP2
pin4    equ 3   ;GP3 input only
pin3    equ 4   ;GP4
pin2    equ 5   ;GP5

        ;bits

rp0 equ 5       ;bit 5 of the status register


Start   org 0x00        ;program starts at location 000
        nop
        nop
        nop
        nop     ;NOPs to get past reset vector address
        nop
        nop


            ;set up to allow counting from external oscillator

SetUp   bsf status, rp0     ;Bank 1
    movlw   b'11110111' ;Turn on T0CKI, prescale for TMR0 = 1:256
    movwf   option_reg
        bcf status, rp0 ;bank 0
    movlw   07h         ;Set up W to turn off Comparator ports
        movwf   CMCON           ;must be placed in bank 0
    clrf    GPIO        ;Clear GPIO of junk
    clrf    units
    clrf    tens
    clrf    Sw_Flag
    goto    Main


Table1  addwf   02,1    ;Add W to the Program Counter to create a jump
    goto    showX0  ;the zero on the right-hand display
    goto    show01
    goto    show02
    goto    show03
    goto    show04
    goto    show05
    goto    show06
    goto    show07
    goto    show08
    goto    show09

Table2  addwf   02,1    ;Add W to the Program Counter to create a jump
    goto    show0X  ;the zero on the left-hand display
    goto    show10
    goto    show20
    goto    show30
    goto    show40
    goto    show50
    goto    show60
    goto    show70
    goto    show80
    goto    show90

    ;Delay 0.005 sec (5mS)

_5mS    movlw   05h
    movwf   File5mS
Del5mS  nop
    decfsz  FileXmS,1   ; ,1 denotes the result of the decrement
    goto    Del5mS
    decfsz  File5mS,1   ;     is placed in the file
    goto    Del5mS
    retlw   00

FastUp  btfss   Sw_Flag,2   ;First time through loop?
    goto    FU_2        ;yes
    btfsc   Sw_Flag,7   ;Has 5Hz bit been set?
    goto    FU_3
FU_1    incfsz  FastCount,1 ;Increment FastCount
    movlw   d'50'       ;determines the time before fast incrementing
    xorwf   FastCount,0
    btfss   status,2    ;reached 50 loops?
    retlw   00
    clrf    FastCount
    bsf Sw_Flag,7   ;set bit for 5Hz incrementing


FU_2    bsf Sw_Flag,2   ;Up button has been pressed
    incf    units,1
    movlw   0Ah     ;put 10 into w
    xorwf   units,0     ;compare units file with 10
    btfss   status,2    ;zero flag in status file. Set if units is 10
    retlw   00
    clrf    units
    incf    tens,1
    movlw   0Ah     ;put 10 into w
    xorwf   tens,0      ;compare units file with 10
    btfsc   status,2    ;zero flag in status file. Set if tens is 10
    clrf    tens
    retlw   00      ;display passes 99 but not below 0


FU_3    incfsz  FastCount,1 ;Increment FastCount
    movlw   d'5'        ;Determines the speed of the increments
    xorwf   FastCount,0
    btfss   status,2    ;reached 5 loops?
    retlw   00
    clrf    FastCount
    goto    FU_2

Dwn btfsc   Sw_Flag,3
    retlw   00
    bsf Sw_Flag,3
    decf    units,1
    movlw   0FFh        ;put FFh into w
    xorwf   units,0     ;compare units file with FFh
    btfss   status,2    ;zero flag in status file. Set if units is 10
    retlw   00
    movlw   09
    movwf   units       ;put 9 into units file
    decf    tens,1
    movlw   0FFh        ;put 0FFh into w
    xorwf   tens,0      ;compare tens file with 0FFh
    btfsc   status,2    ;zero flag in status file. Set if tens is 0FFh
    goto    $+2     ;tens file is 0FFh
    retlw   00
    clrf    tens
    clrf    units
    retlw   00      ;display  not below 0

show01
    bsf status, rp0     ;Bank 1
        movlw   b'00011001' ;Set TRIS  to show seg B
    movwf   TRISIO      ;
    bcf status, rp0 ;bank 0
    movlw   b'00100101' ;
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
        movlw   b'10010011' ;Set TRIS to show seg C
    movwf   TRISIO      ;
    bcf status, rp0 ;bank 0
    movlw   b'00000110'     ;
    movwf   GPIO
    call    _5mS
    retlw   00

show02
    bsf status, rp0     ;Bank 1
        movlw   b'00000101' ;Set TRIS  to show seg A & E
    movwf   TRISIO          ;
    bcf status, rp0 ;bank 0
    movlw   b'00010111' ;
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
        movlw   b'10011000' ;Set TRIS to show seg B & D & G
    movwf   TRISIO      ;
    bcf status, rp0 ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00

show03
    bsf status, rp0     ;Bank 1
        movlw   b'00010001' ;Set TRIS  to show seg A & C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010111'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10011000' ;Set TRIS to show seg B & D & G
    movwf   TRISIO
    bcf status, rp0     ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00


show04
    bsf status, rp0     ;Bank 1
        movlw   b'00010011' ;Set TRIS  to show seg  C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010111'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001100' ;Set TRIS to show seg B & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00

show05
    bsf status, rp0     ;Bank 1
        movlw   b'00010001' ;Set TRIS  to show seg A & C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010111'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001010' ;Set TRIS to show seg D & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00

show06
    bsf status, rp0     ;Bank 1
        movlw   b'00000001' ;Set TRIS  to show seg A & C & E
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010111'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001010' ;Set TRIS to show seg D & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00

show07
    bsf status, rp0     ;Bank 1
        movlw   b'00010001' ;Set TRIS  to show seg A & C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010111'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10011101' ;Set TRIS to show seg B
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00

show08
    bsf status, rp0     ;Bank 1
        movlw   b'00000001' ;Set TRIS  to show seg A & C & E
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010111'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001000' ;Set TRIS to show seg B & D & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00

show09
    bsf status, rp0     ;Bank 1
        movlw   b'00010001' ;Set TRIS  to show seg A & C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010111'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001000' ;Set TRIS to show seg B & D & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00

showX0
    bsf status, rp0     ;Bank 1
        movlw   b'00000001' ;Set TRIS  to show seg A & C & E
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010111'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001001' ;Set TRIS to show seg B & D & F
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100000'
    movwf   GPIO
    call    _5mS
    retlw   00

show0X
    bsf status, rp0     ;Bank 1
        movlw   b'00100000' ;Set TRIS  to show seg A & C & E
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10101000' ;Set TRIS to show seg B & D & F
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100001'
    movwf   GPIO
    call    _5mS
    retlw   00

show10
    bsf status, rp0     ;Bank 1
        movlw   b'00111000' ;Set TRIS  to show seg B
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00100101'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
        movlw   b'10110010' ;Set TRIS to show seg C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000110'
    movwf   GPIO
    call    _5mS
    retlw   00

show20
    bsf status, rp0     ;Bank 1
        movlw   b'00100100' ;Set TRIS  to show seg A & E
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
        movlw   b'10011000' ;Set TRIS to show seg B & D & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000001'
    movwf   GPIO
    call    _5mS
    retlw   00

show30
    bsf status, rp0     ;Bank 1
        movlw   b'00110000' ;Set TRIS  to show seg A & C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10011000' ;Set TRIS to show seg B & D & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000001'
    movwf   GPIO
    call    _5mS
    retlw   00

show40
    bsf status, rp0     ;Bank 1
        movlw   b'00110010' ;Set TRIS  to show seg  C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001100' ;Set TRIS to show seg B & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000001'
    movwf   GPIO
    call    _5mS
    retlw   00

show50
    bsf status, rp0     ;Bank 1
        movlw   b'00110000' ;Set TRIS  to show seg A & C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001010' ;Set TRIS to show seg D & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000001'
    movwf   GPIO
    call    _5mS
    retlw   00

show60
    bsf status, rp0     ;Bank 1
        movlw   b'00100000' ;Set TRIS  to show seg A & C & E
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001010' ;Set TRIS to show seg D & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000001'
    movwf   GPIO
    call    _5mS
    retlw   00

show70
    bsf status, rp0     ;Bank 1
        movlw   b'00110000' ;Set TRIS  to show seg A & C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10111100' ;Set TRIS to show seg B
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000001'
    movwf   GPIO
    call    _5mS
    retlw   00

show80
    bsf status, rp0     ;Bank 1
        movlw   b'00100000' ;Set TRIS  to show seg A & C & E
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001000' ;Set TRIS to show seg B & D & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000001'
    movwf   GPIO
    call    _5mS
    retlw   00

show90
    bsf status, rp0     ;Bank 1
        movlw   b'00110000' ;Set TRIS  to show seg A & C
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00010110'
    movwf   GPIO
    call    _5mS
    bsf status, rp0     ;Bank 1
    movlw   b'10001000' ;Set TRIS to show seg B & D & F & G
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000001'
    movwf   GPIO
    call    _5mS
    retlw   00


;****************************************************************
;* Main                             *
;****************************************************************

Main    bsf status, rp0     ;Bank 1
        movlw   b'11111101' ;Set TRIS
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000000' ;Set GP1 low
    movwf   GPIO
    btfsc   GPIO,3
    call    FastUp      ;UP switch pressed
    bsf status, rp0     ;Bank 1
        movlw   b'11111101' ;Set TRIS
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000010' ;Set GP1 High
    movwf   GPIO
    btfss   GPIO,3      ;down produces 90
    call    Dwn     ;Down switch pressed
    clrf    GPIO
    movf    units,0     ;copy unit value into w
    call    table1      ;unit display value will return in w
    movf    tens,0      ;copy tens value into w
    call    table2      ;tens display value will return in w
    bsf status, rp0     ;Bank 1
        movlw   b'11111101' ;Set TRIS
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000010' ;Set GP1 High
    movwf   GPIO
    btfsc   GPIO,3      ;bit will be zero when sw is pressed - down
    bcf Sw_Flag,3   ;button not pressed. Clear down flag
    bsf status, rp0     ;Bank 1
        movlw   b'11111101' ;Set TRIS
    movwf   TRISIO
    bcf status, rp0 ;bank 0
    movlw   b'00000000' ;Set GP1 low  Testing for UP switch
    movwf   GPIO
    btfsc   GPIO,3      ;UP will be High when pressed
    goto    Main
    bcf Sw_Flag,2   ;button not pressed. Clear Up flag
    bcf Sw_Flag,7   ;Clear Up repeat flag
    clrf    FastCount
    goto    Main

        ;oscillator calibration
    call    03ffh
    movwf   OSCCAL

    end

PARTS LIST

PIC12F629 version with SM LEDs

RESISTORS

(All surface mount 1/10th watt)

• 5 - 47R marked as 470
• 1 - 1k ” ” 102
• 1 - 22k ” ” 223

CAPACITORS

• 1 - 100n surface mount
• 1 - 10u tantalum surface mount (106)

SEMICONDUCTORS

• 1 - surface mount diode 1N4148 (a6p)
• 2 - BC847 - surface mount (1F)
• 2 - BC856 - surface mount (3B)
• 1 - PIC12F629 Micro (00-99 Counter)
• 1 - on/off slide switch
• 2 - tactile switches
• 1 - 8 pin IC socket
• 5 - machine pins
• 28 - yellow surface mount LEDs (30)
• Orange screen 4.5cm x 3cm
• 30cm - fine solder
• 20cm - fine tinned copper wire
• 50cm - 0.025mm enamelled wire
• 1 - 2 Digit Counter PC Board (Experimenter Board)

You will also need the 6 pin to 5 pin adapter for “In Circuit Programming” to connect between the PICkit-2 programmer and the Project ($1.50): A PC board is being produced for the adapter.

GOING FURTHER

Now that you know how to access each of the segments i the left and right displays, you can produce all sots of programs.
Some of the ideas we have in the pipeline include a timer. How many times have you burnt something or forgotten to ring someone back after an hour?
This handy timer has a few buttons and by simply pressing a button it will count down and sound a piezo when the time has expired.
This will be one of the next projects but you can get in first and try your hand at programming.
All you need do is add a buffer to drive a piezo and since all the lines are fully occupied, this will require a clever bit of interfacing.
I will give you a clue how to do it.
The output of one of the lines will contain a delay circuit (say 0.2 second) and when this is kept low, the other line can be used to drive the buffer transistor, as shown in the following diagram:

To order the kit, [send an email](mailto:colin@elechelp.com?Subject=Buying components for the 2 Digit Up/Down counter&Body=Please e-mail the cost of components for the 2 Digit Up/Down counter on prototype PC board and 5/6 pin adapter for $23.00 posted by air mail to my country:****___**** and send details of how I can pay for it. My name is:____**)** to us and we will reply with the details of how to order etc.

If you have any questions on how the circuit works or how to add different features, [email the author](mailto:colin@elechelp.com?Subject=Query on 2 Digit Up/Down counter&Body=Please let me know the following:****___******)** and your answer will be posted here:

• Page 1
• Page 2
• P3
• Page 4(RF Link)
• Page 5