Re: Weird problem writing buffer 1 of a 8250 drive

From: Anders Carlsson (
Date: 2008-09-03 13:50:48


I tried this program in x64 and got it to work after a while:

10 OPEN 1,8,15:FOR I=0 TO 10:PRINT I;
30 FORI=0 TO 10:PRINT#1,"M-R"CHR$(I)CHR$(5)
50 CLOSE 1

Of course I need true drive emulation, but I also had to select a different 
type of drive to get it to work first time, i.e. it defaulted to 1541 in 
which it only returned 199. Then I changed to 1541-II where the program ran 
fine and back to 1541 where it also ran OK. I don't know if the emulated 
floppy drive needs to be enabled in some way. Some sources suggest that you 
should initialize the drive (I0) before the M-W. Perhaps you could also try 
to reset the drive (UJ) to be sure it is in a clean state?

It is true though that when running the same program in xpet and 8250 drive 
(using buffer $12), it hangs. I didn't immediately find any document with 
the 8050/8250 memory map, but I assume you got the number correct, that the 
drive indeed has a RAM buffer in that location?

Best regards

Anders Carlsson

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