Homebrew-radios.net - TrxAVR - minimum components for early testing

Some builders might wish to assemble their TrxAVR board in a way that allows testing of USB connectivity
and ATmega2560 programming at an early stage in the programming.
The advantages of doing this are:

My rig uses a home-made TrxAVR-A controller.
I needed to assemble one of Glenn's TrxAVR-B boards to test a prototype Colour TFT board.
(designed by Chris Stake, drawn up and manuactured by Glenn and programmed by Gerard)
The connection to the colour TFT display I2C is 3 wires: data, clock and ground. There is a 4 pin
I2C bus connector adjacent to the 24LC512 EEPROM for this and other I2C devices.
So I didn't need the parallel display connecting components.

Even without a display connnected, the minimum configuration described below allows you to:

All the above testing can be done with no display and no keypad.

The minumum components to achieve this are:

Connectors:

Other components:

And that's all ...... and the board looks rather empty !

Double click the following images for the high-res version.


TrxAVR-B - minimum config topside. Note that both 5v regulators + caps are installed here (only IC2 needed)
I2C connector installed adjacent to 24LC512 EEPROM.

 


TrxAVR-B mimimum configuration - bottom side. - note: SMD Xtal used here

 


Minimum configuration driving TftAVR and a Truly 480x272 4.5inch display

TrxAVR-Picastar home page