[Coco] Coco "Flash2" cartridge progress

[Ty S]

Hi Mark,

> A little puzzle anyone - how do you think I was planning on doing it without > A14?

 
 
If I were to take a blind stab in the dark (without knowing anything about your design), you could disable interrupts, perform a dummy read from one of the addresses you need decoded to get CTS* low, latch this signal for the next bus cycle, and perform the write using the latched enable signal.
 
Of course, this dummy read would introduce a performance hit -- on second thought though, only the first read would be a true dummy read.  Subsequent reads could verify programmed data:
 
Cycle 1 - Dummy read C000   (CTS* enabled)
Cycle 2 - Write data to C000   (CTS* latched)
Cycle 3 - Read data from C000 for write verify   (CTS* enabled)Cycle 4 - Write data to C001 (CTS* latched)Cycle 5 - Read data from C001 for write verify (CTS* enabled)
 
... and so forth.  Do I win a prize?  :)
 
Ty
 

> > Regards,> > -- > | Mark McDougall | "Electrical Engineers do it> | <http://members.iinet.net.au/~msmcdoug> | with less resistance!"> > --> Coco mailing list> Coco at maltedmedia.com> http://five.pairlist.net/mailman/listinfo/coco

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