NTFS
Member level 3
ppi 8255
Hi
In a project I should to handle many I/Os (GLCD, K/B, many lamps, buzzer, 2 fans, 4 sensors, heater and a DC motor ). So I used two PPI (8255) and micro ports.
Now how can I handle PPI control signals? (A0, A1, RD, WR, CS)
I thing, I should do that manually by micro ports, because I couldn't find a method that when I write to PPI, micro does [WR, A0, A1, CS] signals automatically.
So two questions:
1) what is the best method to interface these many I/Os to micro? Is my method good?
2) How to handle control signals? if I active these signals at a same time, does PPI
work? or I have to do them in separate times? for example first I should active
CS, A0, A1 then put data on port (data bus) and then active WR (write) signal
Thanks in advance.
Hi
In a project I should to handle many I/Os (GLCD, K/B, many lamps, buzzer, 2 fans, 4 sensors, heater and a DC motor ). So I used two PPI (8255) and micro ports.
Now how can I handle PPI control signals? (A0, A1, RD, WR, CS)
I thing, I should do that manually by micro ports, because I couldn't find a method that when I write to PPI, micro does [WR, A0, A1, CS] signals automatically.
So two questions:
1) what is the best method to interface these many I/Os to micro? Is my method good?
2) How to handle control signals? if I active these signals at a same time, does PPI
work? or I have to do them in separate times? for example first I should active
CS, A0, A1 then put data on port (data bus) and then active WR (write) signal
Thanks in advance.