Hi John
 
I am in the process of testing my 16MB Static Ram board dated (19 Oct 2014) 
and I think I have picked up a minor error in the board
regarding the LED indicator lamps.
 
This board (19th Oct 2014) is the one with the LED's in the top left corner 
of the board labelled D2 (8R), D3 (16R), D4 (8W), and D5 (16W)
The problem I have noticed is that when performing 8 bit writes using the 
Z80 monitor D3 (16R) flashes instead of D4.
 
I have continuity checked the traces and have found the following:-
 
U7B Pin 9 (PX2) should connect to Pin 7 of U28 but is in fact connected to 
Pin 5 of U28
U16A Pin 1 (PX3) should connect to Pin 5 of U28 but is in fact connected to 
Pin 7 of U28
 
Somehow the connections to Pin 5 and 7 have got swapped even though the Net 
names on the schematic look correct !!!
 
Please can you confirm this with your board (19th Oct 2014) and post/email 
the Kicad files to the Wiki so that I can see where I can cut traces to 
correct with a wire patch.
 
regards
 
David Fry

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