Re: ROM Dump of Amiga Keyboard controller

From: Gerrit Heitsch <*gerrit_at_laosinh.s.bawue.de*> Date: Sat, 28 Jun 2014 19:12:08 +0200 Message-ID: <53AEF768.2070906@laosinh.s.bawue.de> · gerrit_at_laosinh.s.bawue.de

On 06/27/2014 02:15 AM, Kajtár Zsolt wrote:
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>> As before, I still don't have a clear picture of how exactly is this
>> supposed to work. Either this or the (presumably simpler) approach with
>> an EPROM and a 4040. I think I am not alone in this and that is one of
>> the reasons nobody (including myself) haven't done it yet.
>
> It works the same way as the EPROW+counter approach. Except that the external
> 6502 is the "counter" for addressing the EPROM. Which has the benefit of
> inserting dummy fetches automatically to the bus when needed. This way you
> could use any assembler/monitor to produce the code for the EPROM, without
> tricks. And this 6502 could be used for the communication with the 6500/1 to
> dump it's content too.

An idea worth thinking about. You still have that clock divided by 2 
problem though and have to make sure somehow that the two 6502 are not 
off by half a cycle.

  Gerrit

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