RE: Hardware emulation of 6509 using 6502?

From: Baltissen, GJPAA (Ruud) <>
Date: Fri, 20 Jul 2018 06:43:46 +0000
Message-ID: <>
Hallo Jim,

> > The question is which devices do depend on this?
> Ruud will have to answer.

I only can give you two examples:
- a memory expansion card for the ISA port with SRAM instead of DRAM. My 65816 equipped VIC-20 with ISA expansion would not recognize it.
- my debugger, . It is able to single-step a computer. When stepping, it shows the momentary address and the data on the bus. 
In this case the data was garbled on the display although the VIC-20 ran fine. When I found out what the problem was and had it solved, the display wasn't garbled anymore and the card was recognized.

OK, here was self-built hardware involved. But for me it was anyway a good lesson that if you emulate something, do that as good as possible.

Met vriendelijke groet / With kind regards, Ruud Baltissen


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Received on 2018-07-20 09:00:19

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