Cassette port protocol?

[RobertM]

Can anyone please point me to information on what comes out of the cassette port and what the CPC6128 expects to incoming???

I have tried to search for the file format for the cassette and I only get results for the emulator file formats.

I want to duplicate these signals with a micro-controller so I need to know things like -

The length of a zero and the length of a one

it there a leading section

how is the two chr file name sent

I assume the rest is just binary or is there parity / stop bits?

[arnoldemu]

read soft968 or soft158.
It has the details.

"the cassette manager".

cpctech.cpc-live.com/docs/manual/s968se08.pdf

[RobertM]

Thanks arnoldemu

That mostly makes sense. I just have to work out how to generate the CRC error check bytes. It looks like a Linear Feedback Shift Register (LFSR) - is that right?

[arnoldemu]

Thanks arnoldemu

That mostly makes sense. I just have to work out how to generate the CRC error check bytes. It looks like a Linear Feedback Shift Register (LFSR) - is that right?

8.2 b. "Segments" the crc polynomial is described here.

firmware computes the crc all in software.

The cassette hardware on the cpc is basically a pin on the 8255 to control the tape motor, one for in and one for out.
CPU does all the work reading, detecting waveforms, deciding if it's a 1/0 and calculating crc.

[KaosOverride]

Maybe Playtzx source can help
cpctools/playtzx-0.12b at master · ralferoo/cpctools · GitHub