PK70 QuadUart Blade (NBPKBU-100CR) On aMOD5270 Dev Kit 70

[nemiro]

Hello All-
I have been needing to add more serial ports to a project running off of my MOD5270 equipped Dev 70 kit board. I bought the quad serial UART blade board for a PK70, and wired it according the the pinout in the schematic. I rang out all of the wiring, and it is good. I then adapted the driver files, and attempted to make it work. The code compiles, and when I sent an OpenSerial type command, and send data, I can see a very slight 'wiggle' of the TXA line (port 0) on the oscilloscope, but I do not get any true data through. It is as if something is not enabling. I get traffic on all of the address pins, data pins, and both CS lines. I have tried changing the target in my project to SB70 to no avail, thinking there is some sort of memory mapping difference. Has anyone done this before? I have attached the driver file, which is a modified version of what NB sent me. If someone from NB would chime in, and allow it, I will post their schematic as well. It would be good to have a developed driver set for this setup, as I am sure I am not the only one who needs it. Anyway, if someone could take a look, I would be most appreciative!

[rnixon]

You will always see traffic on the address/data lines, because those are used by the sdram and flash as well. The chip select and clock (if needed) will be key with any peripheral like this. If you are at a point were things don't work I would go back and check all the signals to ensure you have the proper ones connected. Verify any timer or clock signals; what clock and frequency are you using? If all else fails, use a scope, trigger of the chip select for the device, and see if the correct information is being sent to whatever external part you are using. Any wiggles you see on the output lines could just be coupling to the clock for the chip, unless you can actually scale it up and verify it is the serial chars you are sending.

[nemiro]

I do get the proper chip select. I plan to drag out an old HP logic analyzer I have, and see if I can line up all of the pertinent data lines, and take another look.

The wiggle I get does correspond to when I send data through the device (I click a link I have to send the data).

[pbreed]

What pins have you connected?

[nemiro]

I connected only the ones that were actively being used in the schematic. So, D24-31, A0-A4, CS1, CS2, RSTI, RSTO, IRQ1, IRQ3, GND, VCC3v.

[pbreed]

Do you have anyother hardware using the data bus?

If so what memory space is it mapped into, the
Quad Uart driver uses 0xA0000000

Paul

[nemiro]

Nothing else on the bus, outside what is already on the Dev70 kit board. Everything else I have is discrete I/O on the J2 connector. One of the NB engineers thinks I may be having bus 'reflection' issues. I am in the process of rewiring the connectors away from wire wrap & ribbon cable to AES 110ohm short wires (~2"). I will report back on what I find here later on.

[nemiro]

Thanks for everyone's help, I did get it going! It turned out to be an issue with identifying the fd 's (fd_serial). This might be something elementary to an experienced NB user, but to the newcomer, it threw me for a loop, despite plenty of embedded C experience with other platforms. At any rate, it is now working, and I really appreciate all of the responses that people sent to me!