« previous next »
Pages: 1 2 3 [4] 5 6 7   Go Down

Author Topic: Sys 80 Non CPU boot/IRQ issue  (Read 3616 times)

0 Members and 8 Guests are viewing this topic.

Offline MartyJ

  • Trade Count: (+4)
  • ******
  • High Score Initials:
  • Forum Posts:
    • Melbourne
Re: Sys 80 Non CPU boot/IRQ issue
« Reply #45 on: May 30, 2009, 01:45:24 PM »
New CPU in, couple of this resolved but still IRQ high.

From reading the schematic, IRQ begins at pin 4 U1 (6502) goes via R1 & R2 to pin 16 TC1 then to pin 25 U4, U5 & U6.

Is there anything prior  to U1 which has anything to do with IRQ?
Logged
Pages: 1 2 3 [4] 5 6 7   Go Up
« previous next »