68kMLA Classic Interface
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| Click here to select a new forum. | | Hanging Out with a pack of Wombats | Posted by: Phipli on 2024-01-18 07:53:09
Probably, but only Centris 650 have LC040 IIRC - Quadra 650 and 800 have full '040.
I'm trying to understand the signal termination requirements of the MC68040, and it seems Apple has done it all: I can't see any termination for A/D on the Q900 schematics, it's present but labelled "for 40 MHz operation with large buffer" for Q650/Q800 (which I'm trying to confirm are always using small buffers and no termination), and are always present/large buffers on the 840AV... This is a Quadra 650 - 33MHz with Ethernet. Will have shipped with a full fat 040. | Posted by: Phipli on 2024-01-18 08:00:07
View attachment 68343 by the way, what is the code on these fuses? Trying to find replacements. All three of F1, F2 and F3 are labelled X125.
It is a 1.25A part. | Posted by: Melkhior on 2024-01-18 08:05:13
This is a Quadra 650 - 33MHz with Ethernet. Will have shipped with a full fat 040. Thank you! So yes, small buffers, no termination (RCD1 to 7 are not installed), as expected - but better to be certain 🙂 | Posted by: Joopmac on 2024-06-03 00:21:57
Yes funny the differences between wombat boards, I have a q800 with 55mhz 88916 and 8mb ram and rom slot, a q650 with 4mb ram / 70mhz 88916 without Rom slot, a q650 without Rom slot with 8mb and 70mhz
They seem to come in a lot of flavours | | < 2 |
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