Re: [cosmacelf] Re: Glad To Be Part Of This Group
- On 12/7/2011 11:20 AM, Marc wrote:
>Yeah, that was the name! Thanks for the reminder.
> Hi Lee,
> I googled what you mentionned regarding the PIC 1802 emulator and came up with Ted Rossin at http://www.tedrossin.0sites.net/Electronics/RCA/RCA.html
One implementation used an 8-pin PIC as the "1802", with serial shift
registers to provide the Elf's usual 8-bit parallel input and output
ports. He had the usual control switches as well, so you could load a
program with switches, and run it. The only limitation was that he only
had something like 64 bytes of program memory.
There was also an Elf with a larger PIC in place of the 1802. This PIC
provided more memory and I/O. Though the resulting chip count was about
the same as an equivalent design with a real 1802.
I think it would be fun to aim for something in between. Use a larger
PIC, and minimize the number of external chips, so you have a fully
functional Elf with (say) half the chips. :-) It could include the 1861
as well, which means the PIC replaces two rather hard-to-get chips.
Lee A. Hart | Ring the bells that still can ring
814 8th Ave N | Forget the perfect offering
Sartell MN 56377 | There is a crack in everything
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