Hello everyone o/
I began to study the work of Atari SIO and ran into an interesting question.
I connected the Arduino to the Atari SIO pins and started listening to the broadcast that Atari asks for when it is turned on.
The first 28 packages were standard:
Received data: $31, $53, $0, $0, $84
CRC: Calculated: $84, Received: $84, Status:OK
Device: $31 ("1")
Command: $53 ("Get Status")
Atari tries to interrogate the first device ($ 31 = D1:) and requests its status.
Having exhausted all attempts, my atari requested an unknown device ($ 4F) and tried to send an unknown command ($ 40):
Received data: $4F, $40, $0, $0, $8F
CRC: Calculated: $8F, Received: $8F, Status:OK
Device: $4F ("O")
Command: $40 ("Unknown")
I found a description of the commands and device IDs on the site atarimax, but there is no $4F device among them and the $40 command is also not known.
Google search also failed.
Perhaps this is no secret to anyone and the information is available.
But I managed to find only the mention of the device ("O") in the RespeQt program.
Someone can tell where to find out a little more information.
Thank you in advance!