I'm trying to interaface with an 8080bus, that's the schematic of the socket of it:
I'm latching all of the signals, A1,CS1,CS2, IOWR as clock to LS374, and the databus.
Here is the schematic of the board that has the two latches connected
I'm powering the latches from STM32F429I Discovery board, 5V, GND. The ground of the Device 8080 is connected to STM32Board and to the PCB of the two latches.
I captured the data using logic analyzer, here is the data:
MPC LATCH IOWR
6E 30 1
7E 30 1
7A 30 1
21 30 0
21 30 1
21 21 1 <--- latch is valid here
7F 21 1
7E 21 1
7F 21 1
7A 21 1
6A 21 1
7A 21 1
71 21 1
61 21 1
66 21 1
76 21 1
7A 21 1
6A 21 1
7A 21 1
78 21 1
68 21 1
60 21 1
70 21 1
76 21 1
7F 21 1
6F 21 1
60 21 1
7F 21 1
6F 21 1
61 21 1
7D 21 1
6E 21 1
78 21 1
7F 21 1
6F 21 1
6A 21 1
7A 21 1
71 21 1
61 21 1
68 21 1
78 21 1
74 21 1
24 21 1
21 21 1
6F 21 1
62 21 1
72 21 1
7A 21 1
79 21 1
69 21 1
63 21 1
7F 21 1
78 21 1
79 21 1
69 21 1
6E 21 1
67 21 1
77 21 1
7D 21 1
6D 21 1
6F 21 1
7F 21 1
76 21 1
66 21 1
60 21 1
70 21 1
78 21 1
7A 21 1
6A 21 1
61 21 1
70 21 1
73 21 1
3E 21 0
3E 3E 1 <--- latch is valid here
7F 3E 1
70 3E 1
7E 3E 1
6F 3E 1
60 3E 1
70 3E 1
78 3E 1
68 3E 1
60 3E 1
70 3E 1
77 3E 1
67 3E 1
6F 3E 1
7F 3E 1
70 3E 1
75 3E 1
65 3E 1
6E 3E 1
7E 3E 1
7A 3A 1 <--- latch is corrupted here
20 12 1 <--- latch is corrupted here
20 3A 0 <--- latch is corrupted here
20 20 1
7F 20 1
75 20 1
65 20 1
6F 20 1
7F 20 1
77 20 1
67 20 1
69 20 1
79 20 1
7F 20 1
6F 20 1
7F 20 1
70 20 1
68 20 1
78 20 1
I have no idea what's going wrong, and why the latch works for few moments and then is corrupted.