Run/Stop Restore doesn't work
Posted: Tue Apr 09, 2024 3:28 am
Hi all,
I had a problem with the right switch of the joystick and I solved changing the 6522. I put the newer one using a socket (originally all ic are solded directly on the mainboard). The 6522 is the right one, that one close to the keyboard connector.
Now the joystick works but the Run/Stop Restore no more.
The restore pin is correctly connected to the UAB3 6522 at pin 40. The pin 21 of UAB3 is connected correctly at pin 6 of 6502.
The key Run/Stop works. Run/Stop and Restore instead doesn't work.
I know that UAB3 should low the pin 21 when the pin 40 go at ground on Restore switch but nothing happens, I think the press of Run/Stop should do something in order to do that but how can I test if all is ok? That is, pin 40 go low (not completely at ground directly) and the Run/Stop in which way let 6522 pin 21 to go low?
I though that maybe using a socket some connection between the two 6522 is broken, there are connection on the top of the board and I solded only the bottom. Could be this the problem?
The Vic seems to work fine , no other problems.
p.s.
Originally there were two MOS6522-3283. I changed one with MOS6522-2518 12. I tried to put the old one but nothing changed
Thanks in advance for your help
Fabrizio
I had a problem with the right switch of the joystick and I solved changing the 6522. I put the newer one using a socket (originally all ic are solded directly on the mainboard). The 6522 is the right one, that one close to the keyboard connector.
Now the joystick works but the Run/Stop Restore no more.
The restore pin is correctly connected to the UAB3 6522 at pin 40. The pin 21 of UAB3 is connected correctly at pin 6 of 6502.
The key Run/Stop works. Run/Stop and Restore instead doesn't work.
I know that UAB3 should low the pin 21 when the pin 40 go at ground on Restore switch but nothing happens, I think the press of Run/Stop should do something in order to do that but how can I test if all is ok? That is, pin 40 go low (not completely at ground directly) and the Run/Stop in which way let 6522 pin 21 to go low?
I though that maybe using a socket some connection between the two 6522 is broken, there are connection on the top of the board and I solded only the bottom. Could be this the problem?
The Vic seems to work fine , no other problems.
p.s.
Originally there were two MOS6522-3283. I changed one with MOS6522-2518 12. I tried to put the old one but nothing changed
Thanks in advance for your help
Fabrizio