BASIC audio files for testing

[bxdanny]

Yes, what you described would mean the serial port was running at 600 bps. And since the OSIKCS program has an option to support 600 bps "tape" files, I wonder if you would be able to load audio files created using that -R1 option.

[Sideburn]

Yes, what you described would mean the serial port was running at 600 bps. And since the OSIKCS program has an option to support 600 bps "tape" files, I wonder if you would be able to load audio files created using that -R1 option.

Ok I will try that before undoing the wiring back to default 300.

[Mark]

600 baud is somewhat flakey for OSI cassette. There are only 2 cycles of 1200Hz for a "0" bit, and a 1 Mhz OSI has trouble keeping up with tokenizing long BASIC lines without having extra end of line NULLs added when SAVING. 600baud works better with non-basic data I/O (checksum or monitor load files).
OSIKCS can generate 600 baud files, but doesn't decode them very well.
Also note OSIKCS actually generates ~305 baud files as the sample waveforms sync at that rate and the resulting WAV file can be losslessly greatly compressed. This is generally not a problem for the OSI hardware, but you can hear the frequency difference between an OSI idle "carrier" 2400Hz and the files generated by OSIKCS (2450Hz).

[Sideburn]

Alright I will go ahead and undo the mod and put it back to stock 300 now and the. I will try a save and a load from the board and see how it goes.

[Sideburn]

OK I ran some tests.. Something is still not right.

Now when I save, the baud rate does seem slower but I still cannot load.

Am I doing this right? I am typing LOAD <return> and I get an OK and then I hit play and nothing happens.

Attached are two .wav files:

save300.wav is the recording of the super board saving. The tone is different than what the OSIKCS tool generated.

speed.wav is my test file generated from OSIKCS tool.

Neither will load into the board.

[Mark]

I think the cassette "mark" frequency is now half of what it should be. (1200Hz instead of 2400Hz)
Previously the clock for the cassette tone generator was correct, it was just that the clock for the 6850 (pins 3 & 4) was 600 baud (9600Hz) instead of 300baud (4800Hz). Not sure where the modification was made exactly, but you should be able to locate it by tracing the clock pins of the 6850 to its source. Someone with a C1P may be able to help.

[Sideburn]

OK I will investigate some more.

Does the speed.wav see right? That one i generated from the osikcs tool. It would be helpfu to have a known working wav file as a base to rule out the creation of a file part to get loading to work. Right now I don't know if any of my audio files are any good.

[Sideburn]

I see a jumper on the 6850 from pin 5 to U18 pin 9.

The 6850 pin 3 & 4 are tied together and go to U63 pin 9. This seems normal.
But on the underside of the board U63 pin 8 and 12 are tied together and then jumped over to pin 3 of U44 which has a 74LS74 on it.

[Sideburn]

Hey all,

I was going to get the board out today and work on getting save / load again.

I’d like to first nail down saving and not rely on the board to do the load.

Two ways I figured I could go about this:

1) I could save some programs out as .wav files and then see if one of you would be willing to see if you can get them to load on your board.

2) maybe I can install a board emulator on my modern computer and use that to test loading the files with?

Any suggestions ? I beleive there is an emulator out there correct? Will it load wav files?

[bxdanny]

It would be a two-step process.

Certainly, you should download and install the WinOSI emulator from Mark's site if you haven't already. It doesn't directly read audio files, but it does let you LOAD text files as simulated "tapes". And you can use the OSIKCS program, from the same site, to convert valid Kansas City Standard audio files into text files you can use for that purpose.