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Topic: Computerless Bus Pirate  (Read 128 times) previous topic - next topic

Computerless Bus Pirate

Hello everyone,,
i'm a newby with pic and atmel based hardware and just started playing with the teensy 2.0 and a bunch of part from 4D system and sparkfun... however, i have a lot of experience with programming of embeed  device (mostly sigma, motorola SoC based tv stb)... So please feel free to correct me in any of the assumption i'm going to make regarding the hardware interface are wrong, i want to learn that stuff.

Inspired by the computer-less adruino project (which is awesome btw!) i am building a computer-less serial console that i would like to use with the BP... I am trying to use the uLCD-32PT from 4D System as a serial console display for the serial text output and a blackberry keyboard connected directly to the uLCD-32PT GPIO (still have to figure out the keyboard part, will probably code an onscreen kb for now).

I would like to connect the serial ttl port of the inteligent lcd display module to the BP v3 in this configuration;
host: uLCD-32PT
slave: BP v3

I was wondering why the tap between the pic and ftdi chip had been removed in v3? i believe this is where i need to connect the ttl interface of the host. (only have BP v3 in hand for now)

ftdi chip documentation show that by default it is configured for rs232 application, if i follow the pin used on the BP v3, this seem to be accurate.

uLCD documentation show
-Easy 5 pin interface to any host device: VCC, TX, RX, GND, RESET.
-Asynchronous hardware serial port, TTL interface, with 300 baud  to 256K baud.

Am I missing anything? i believe i just have to tap the tx, rx pin of the ftdi chip and plug straight into the uLCD serial ttl?? or do i need a max232 chip in between?

Any help will be appreciated, also, are you planning to make a portable device like the dso nano oscilloscope but for logic and protocol analyzer? i would be happy to help with the coding or share my serial console display library ;)

Re: Computerless Bus Pirate

Reply #1
Hi Wanhedaking,

You would need to tap or bring out the RX and TX of the UART and then interface it at 115200 baud with settings 8/N/1.

The extra UART pins I assume were eliminated because we needed them for other functions. However, I'm not sure, but I believe the programming pins (ICSP) pins are PPS pins, so you could technically update the firmware to assign the UART to those pins instead of the FTDI chip.

If you're into something new and more powerful (and with a display), Sjaak and I have been messing with this: http://dangerousprototypes.com/forum/index.php?topic=10316

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