FTDI ATmega

From BitWizard WIKI
Revision as of 16:00, 6 January 2012 by David (talk | contribs) (Arduino Pinout)

Jump to: navigation, search

FTDI-atmega

This is the documentation page for the FTDI-atmega PCB.

overview

The FTDI-atmega PCB has an USB connector and a 20-pin IO connector. The brains of the PCB is an ATmega168 chip.

External resources

pinout

The 20 pin connector is connected as follows

1GND
2GND
3PC3
4PC2
5PC1
6PC0
7PB5
8PB4
9PB3
10PB2
11PB1
12PB0
13PD7
14PD6
15PD5
16PD4
17PD3
18PD2
19VCC
20VCC
  • led1 is connected to VCC (the top one, called led2 on V7.0)
  • led2 is connected to CBUS0 (FT232RL) PC -> AVR activity
  • led3 is connected to CBUS1 (FT232RL) AVR -> PC activity
  • led4 is connected to PC5
  • led5 is connected to PC4 (absent on V7.0)

Arduino Pinout

When using the Arduino IDE, the layout of the header is as follows:

GNDGND
A3A2
A1A0
1312
1110
98
76
54
32
V+V+
  • Unlike a regular arduino, the onboard LED is connected to pin A5. This means pin 13 is free for regular use.
  • Pin 0 and 1 are used for the COM interface like a regular arduino.

programming

This section describes how you get your program into the processor.

Linux

You can program the processor using any ICSP programmer that you might have. In that case, the jumper SV1 should then be in the upper position (away from the ICSP connector).

Or you can program it with the ftdi bitbang programmer included on the board.

Here is the documentation: http://www.geocities.jp/arduino_diecimila/bootloader/index_en.html

The ftdi-bitbang programmer-driver for avrdude is not included in the standard avrdude program. The reason is that the patch uses the ftdi library FTD2xx and not the open source libftdi.

In the avrdude bug tracking system another patch is doing the rounds, but that one is really slow because it doesn't exploit the ftdi's synchronous mode.

A precompiled avrdude version can be downloaded here: http://www.bitwizard.nl/avrdude.zip . The zipfile contains "quick and dirty" instructions to replace the avrdude binary in /usr/bin with a script so that when "arduino IDE" calls it, the program gets programmed into the board.

TODO: port the fast ftdi bitbang code to libftdi and submit to avrdude.

windows

See the linux section above.

writing programs

The chip is an ATmega168. http://www.atmel.com/dyn/resources/prod_documents/doc2545.pdf

future hardware enhancements

Provide a 3- or 4-pin header with the i2c pins (to communicate with wiimote and other peripherals). The leds need to be disabled for this to work. :-(

future software enhancements

Changelog

7.0

  • Initial public release