Re: FPGATED

From: Segher Boessenkool <*segher_at_kernel.crashing.org*> Date: Sat, 23 Jul 2016 13:22:18 -0500 Message-ID: <20160723182218.GA13327@gate.crashing.org> · segher_at_kernel.crashing.org

On Sat, Jul 23, 2016 at 06:29:33PM +0200, Michał Pleban wrote:
> > Next project would be a replacement 8501 since those also die easily...
> 
> That should be much easier, as no analog stuff (video) is needed and a
> 6502 core is easily obtainable... Somebody should really make such
> project :-)

The visual6502 project has a die picture of an 8501.  From the picture
it seems clear that both the 8500 (c64c) and 8502 (c128) used the same
silicon, with different contacts bonded out.

<http://visual6502.org/images/pages/MOS_8501_die_shots.html>

From the top left (counting the corner as "left"), going counter-clockwise,
you have:

left: AEC Vcc A0 A1 A2 A3..A10
bottom: A11 A12 A13 Vss A14 A15 GATE P6 P5
right: P4..P0 D7..D3
top: D2 D1 D0 R/#W PHI2 #RES PHI0 RDY #IRQ SYNC #NMI

8500 does not have GATE P6 SYNC
8501 does not have PHI2 SYNC #NMI
8502 does not have GATE PHI2 SYNC

(I am not sure "SYNC" really is SYNC; it is an output only though).

Segher

       Message was sent through the cbm-hackers mailing list