Commit 30bd65e2 authored by natalie's avatar natalie 💜

fix speech eprom board IC list

parent d33e923f
......@@ -7,13 +7,14 @@ On my specimen, /OE appears to be shorted to ground. I do not actually see where
Both halves of a CD4556B are used to select EPROMs. Since my board only had the first three positions populated, I did not trace out the second half of the demux. I would assume this is just sitting on the CPU bus as standard address decode logic in the device, although the particulars don't really matter for externally dumping the roms. Standard input applies on the CD4556B - treat A and B as bits 0 and 1 respectively, which selects the appropriate rom.
Working left to right, bottom to top:
IC1 MC14503B
IC2 MC14503B
IC3 CD4069UB
IC4 MC14503B
IC5 CD4556B
IC6 MC14503B
IC7 MC14503B
| Name | Part |
| IC1 | MC14503B |
| IC2 | MC14503B |
| IC3 | CD4069UB |
| IC4 | MC14503B |
| IC5 | CD4556B |
| IC6 | MC14503B |
| IC7 | MC14503B |
Backplane pin numbers are specified as labeled on the connector shell.
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