TrxAVR_Picastar - Port diagnostics

The hardware port diagnostics provision consists of:

First a quick summary of the stages/levels in getting trxAVR-Picastar up and running.
(See setup instructions for more detail)

If all this doesn't happen - then there may be a hardware fault and the hardware diagnostics may useful.

The following are important in diagnosing hardware faults:

We have two situations:

  1. USB working - so we can use the USB link to look at the ports except Port D bit 2-6
    - yes we can look at PORTC via USB (It is momentarilty taken over for USB data and then released back to our testing.)
  2. USB not working. This where the separate tiny application TestPortsCD.hex can be used to check out ports C and D
    which are used by USB and may have a problem.

USB working - Hobcat's PortDiagnostic window.

This is called from Menu | Tools | TrxAVR port diagnostic and is shown below:
(Note: this window will not be active until DSP load is completed (very brief if no DSP code loaded yet!)

The window displays all bits of all ports except PORT D bits 2 - 6 which are FT245R USB control signals.
It can be be used in Read or in Write mode:

The first Read or Write action, as above will put TrxAVR-Picastar in diagnostic mode. A rig reboot is thereafter required to
restore normal operation.

Serial and encoder interrupts are disabled, internal timers are disabled and the analogue inputs become digital I/O.

PORT C is used for USB data but only momentarily. On Read mode, the 1k serial input resistors prevent the applied
logic level from interfering with FT245R-Atmega2560 communication. (But dont connect inputs direct to the port!)

USB not working

TestPortsCD.hex is program which simply sets PORTC andPORTD as outputs (DDRC=0xFF, DDRD=0xFF)
and cycles the output states. TestPortsCD.hex is loaded using the programmer (ie: AVRISP2, Ponyprog)

Each half of PORTC and PORTD behaves as a 4 bit counter at 0.5Hz. (ie counts 0 - 15 repeatedly)
Short circuits are likely between adjacent pins and so the main requirement was that adjacent pins shoul have different
signal patterns.

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