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Re: [MiNT] lp driver patch for the Firebee to extend the parallel port strobe duration
Am 04.10.2015 um 00:59 schrieb Alan Hourihane:
Hi Markus,
Why can't this problem be entirely fixed within the FPGA and not resort
to these additional requirements ?
Alan.
Am 04.10.2015 um 00:59 schrieb Alan Hourihane:
Hi Markus,
Why can't this problem be entirely fixed within the FPGA and not resort
to these additional requirements ?
Alan.
Hi Alan,
sure, the Firebee's high PSG port switching rate could be slowed down to
the speed of a Falcon by inserting wait states in hardware in the FPGA
config until the 750 ns required by the IEEE 1284 (Centronics) specs are
met.
We then had a (fixed) much slower achievable toggle rate (not only for
the strobe signal, but probably for the other PSG ports and other
possible uses of the parallel port as well).
Just because the software was originally tailored to a specific hardware
that only needed two NOPs instead of 21 because it was much slower. The
most compatible machine to a Falcon is a Falcon .
Seriously, I don't think that would be the right thing to do.
The Firebee is intended to be as fast as possible and if specific specs
for a specific use require it to slow down in places, in my opinion this
rather should be done in that part of the software for that specific
purpose (printer) instead of generally limit its hardware capabilities.
I'm open for discussion, but that's my feelings.
Cheers,
Markus