KY11-LB drawing error
jnc at mercury.lcs.mit.edu
Sat Apr 16 13:03:27 CDT 2016
So, now that I have the 85S68 datasheet in hand, it turns out there's an error
in the KY11-LB drawings. (I just couldn't understand how the circuit could
possibly work, until I discovered that!)
On the two RAM chips (E11 and E27, used to hold the bus address, keypad data,
etc) the "Output Store" and "Output Disable" labels are reversed. (Not the pin
numbers, etc - just the labels.) I.e. 'Output Store' is actually pin 13; it is
tied high (as shown on the drawings for that pin).
I have 'fixed' a copy of that page from the print set, and will (soon) issue
an updated PDF.
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