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AMSAT-NA / PacSatSW

MIT License
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The number of AX25 preamble bytes should vary based on baud rate and back to back packets #17

Closed ac2cz closed 1 year ago

ac2cz commented 1 year ago

Right now the number of preamble bytes is hard coded to a value that works for 9600bps in the lab. This value should be configurable and should vary based on the rate. Testing should be performed to optimize the value.

In addition, the preamble bytes may not be required if frames are sent back to back. This would greatly improve efficiency.

ac2cz commented 1 year ago

The preamble bytes also need to be updated if the rate is changed by a command or from the console. Currently that calls the radio start/stop functions. If will need to send a message to the TxTask to let it know the rate has changed. Perhaps that is where the radio stop/start commands should execute from.

ac2cz commented 1 year ago

This should be implemented so that it also solves #15. We should commit the packet bytes 200 at a time to the FIFO and wait for the interrupt to add more. If we have another packet available as we are adding the last bytes for a packet, then just insert a very short preamble. If it is the first transmission after a gap then insert the full preamble.

ac2cz commented 1 year ago

Fixed in 0.1g but does not solve #15. Just implemented as a check in TxTask()