IRQ-4

Hello, Alexander! Once, Alexander Araktcheew tormented Klava about "US Robotics Sportster 14400" wanted to tell me... AA> I would also like to see the nmi generation circuit from the modem c AA> using a standby multivibrator. I did as in AA> drive controller, but it's some kind of garbage. Modem at AA> working in S-TERMINAL puts irq4 in eternal zero and the scribe. I don’t know where you got the standby multivibrator, but the standard the scheme is like this: 555TM2 ┌─┬───┐ ─°r│ q ├─ z80 a11 ─────┤d│ │ 555LA3 iow modem ─────┤c│ _ │ ┌───┐ z80 reset ─────°s│ q °─────┤ & °─── z80 nmi └─┴───┘ ┌──┤ │ │ └───┘ └── modem irq4 And don’t forget to flash the ROM - it’s necessary for this fix NMI processing error, if of course it is not already there fixed: address data acc. commands #0066 F5 PUSH AF #0067 E5 PUSH HL #0068 2A B0 5C LD HL,(#5CB0) #006B 7C LD A,H #006C B5 OR L #006D 28 01 JR Z,#0070 20 01 JR NZ,#0070#006F E9 JP (HL) ^^ ^^ #0070 E1 POP HL That's the error #0071 F1 POP AF #0072 ED 45 RETN Best regards, Sasha.