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Re: [MiNT] lp driver patch for the Firebee to extend the parallel port strobe duration
On 04/10/15 01:16, Markus Fröschle wrote:
> 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 ?
> 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 inthe
> FPGA config until the 750 ns required by the IEEE 1284 (Centronics)
> specs are met.
> We then had a (fixed) much slower achievable switching rate (not only
> for the strobe signal, but probably for all 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 the
> hardware capabilities.
> I'm open for discussion, but that's my feelings.
But by fixing the MiNT lp driver, what about applications running under
FireTOS without MiNT and access the parallel port - won't they all need