Yesterday I ported the custom transfer routines of my cassette-to-RS232 adapter to the PET. The first mistake that I made was a very stupid one: I wasn't able to load the transfer program to the PET, because the tape header identifier byte was 3 and not 1, the only code the PET appears to accept for programs. As the computer didn't display any "found" message or anything, I was puzzled for a long time. It was not too difficult to get the transfer going in cassette port #1. But the second cassette port is more problematic, since the VIA clears the status of CB2 (cassette #2 read) every time port B is read or written (and cassette write is PB3). Hmm, maybe I should misuse the data direction register and use the pin as an open-collector output (acting either as a constantly-zero output or as an input). The microcontroller has internal pull-up resistors. Well, my actual question is: Why does the PET 8032 firmware contain the start-up message both with the ### and the *** signs? I thought that the type of the message identified the BASIC ROM version. (I noticed this when I tested the transfer protocol by dumping the ROM.) Marko Message was sent through the cbm-hackers mailing list
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