# HG changeset patch
# User Tormod Volden <debian.tormod@gmail.com>
# Date 1390077884 -3600
# Node ID 8629f64b7dd309e2c032d9691b0f0caaaed2d77b
# Parent  4ec45bc242781af182b1a0701a191bee9ab4c954
rominfo: Disable autostart interrupt signal from ROMPak

For autostarting ROM cartridges the expansion port CART
input is taken to CB1 on PIA1 in order to trigger FIRQ.

If we don't disable this input on the PIA we will
get FIRQ's all the time.

Bit 0 of CRB (control register B) defines whether the CB1
input will trigger IRQB MPU interrupt on the PIA.
(IRQA and IRQB are connected to FIRQ on the 6809)

diff -r 4ec45bc24278 -r 8629f64b7dd3 level1/modules/rominfo.asm
--- a/level1/modules/rominfo.asm	Sat Jan 18 10:12:28 2014 +0100
+++ b/level1/modules/rominfo.asm	Sat Jan 18 21:44:44 2014 +0100
@@ -147,7 +147,11 @@
          clr   -2,x
          bitb  2,x
 
+         IFNE  ROMPak
+         lda   #$36                    inhibit ROMPak autostart FIRQ
+         ELSE
          lda   #$37
+         ENDC
          sta   PIA1Base+3
 
          lda   PIA0Base+3