Wiegand data and com port

[Felch]

Hi!
My code is also used in a networked access system... I DID have to cut out some parts of it since i am not allowed to distribute it. Nevertheless i hope it will help you. Comments are in Estonian but code in pure assembly
I do not use UART for RFID-s but RB4...RB7 port's port change int.
Mail me if anything remains unclear or needs to be translated.

/Felch
PS. I am also working with radioactivity monitoring system. It will be something like a portable datalogger equipped with GPS. Data is stored on an MMS card. Presently busy with FAT code. How does your appartus look like?

EDIT: It crossed my mind that if you have your readers data-pins, say D0, wire-ored together to generate an RB0-int, then read (in the int routine) readers ports and save them for processing, one could service 8 or even more RFID-readers. May-be even simultaneously if PIC is fast enough. In the int routine one only needs to shift some bits, that's all!
This kind of approach seems to be used in commercial security systems.

EDIT: Mistake in circuit - BUZ and LED are actually B-readers datapins D0 and D1 .

[Yuantu Huang]

Hi Allan,

I am using PIC16F737 internal clock 8MHz, Card 1 is connected to RA6 and RA7, Cards 2, 3, and 4 are connected to PORTC<0:2,5:7>, and Cards 5,6,7,and 8
are connected to PORTB. All 16 card pins 1K resistors pull up to 5V.

I use the following code to determine which card has presented.

MainLoop:
CurrCard = 0
' Card reader 1
CheckPortA:
TempVar = PORTA
if TempVar < $C0 then CurrCard = 1 : goto FoundCard

' Card readers 5, 6, 7, and 8
CheckPortB:
TempVar = PORTB
if TempVar < $FF then
if TempVar.0 = 0 then CurrCard = 5 : goto FoundCard
if TempVar.1 = 0 then CurrCard = 5 : goto FoundCard
if TempVar.2 = 0 then CurrCard = 6 : goto FoundCard
if TempVar.3 = 0 then CurrCard = 6 : goto FoundCard
if TempVar.4 = 0 then CurrCard = 7 : goto FoundCard
if TempVar.5 = 0 then CurrCard = 7 : gosub FoundCard
CurrCard = 8
goto FoundCard
endif

' Card readers 2, 3, and 4
CheckPortC:
TempVar = PORTC
TempVar = TempVar & %11100111
if TempVar < %11100111 then
if TempVar.0 = 0 then CurrCard = 2 : goto FoundCard
if TempVar.1 = 0 then CurrCard = 2 : goto FoundCard
if TempVar.2 = 0 then CurrCard = 3 : goto FoundCard
if TempVar.5 = 0 then CurrCard = 3 : goto FoundCard
CurrCard = 4
goto FoundCard
endif

goto Mainloop

FoundCard:
select case CurrCard
Case 1: ' scan card 1
...
end select
...
goto Mainloop

[alind]

Thanks Felch and Yuantu, looks like I have plenty to get started with now!
Regards,
ALlan

[jmaloway]

Hey there,

Felch,

I have been reading this thread and am really interested in giving this project a try, the only problem is that I can't seem to sucessfully burn a PIC - I have tried almost every method possible and I was wondering - Could I buy a pre-programed PIC from you? I live in Canada and would of course pay for all shipping costs.

Thanks,

James.

[Felch]

Hi!
Sure i could send you preprogrammed chip but is this really what you want? It could cost a lot...
Wouldn't it be easier to fix your programmer? What device are you using and what errors does it generate?
Anyway, if you still prefer a preprogrammed chip, send me your address. I will charge the cost of chip and nothing more. I guess that it is possible to send it with "receiver pays" option?

rgds,
/Felch

[jmaloway]

Felch,

I don't know. I've never been good a programming - for any platform. I used to know a bit of Qbasic, but that's about it. Because I don't understand the language the code it written in, I have no idea where to look for errors. I didn't get any error messages when I burned your code onto a PIC, but it dosen't do anything when you power up the chip. I am a more electronically-minded person, I have no problems with the physical aspect such as wiring up the board, but software issues are simply beyond me. Below is what I did to burn the code onto a PIC16F628A using a JDM programmer:

1. Saved code from your website as .asm file
2. Opened "Pony Prog 2002" and opened the ASM file.
3. Clicked "Write to Chip"
4. Got the message "Write Sucessful"
5. Wired up the chip with specified crystal, 22pF caps, Miniprox reader and powered it from +5V from my USB port.
6. The reader powered up and completed the power-on self test.

That's as far as I've gotten. I have playing around with MPlab, but it is ridicusly overcomplicated for me.

Am I doing everything right? I have gone to all sorts of different websites and read tons of different beginner's guides to programming PICs but I still don't get it.

Let me know if I am doing something wrong, and If I'm not then I'll just buy a chip from you. Do you have paypal?

James.

[Felch]

Hi!
It must be a PIC12F629, not 16f628! That's first. Then, After powering up the chip has no tasks, nor does it output anything. Only after you have presented a card (wiegand data arrives from reader to PIC), card number is output via serial port. Perhaps this helps?
Let me know if it still does not work.

/Felch

PS. Do NOT forget to read PICc's internal calibration data and then burn it back. Otherwise serial comms speed would be incorrect! If programmer asks if it should use OSCAL from file or from chip, say use data from CHIP!