diff options
Diffstat (limited to 'src/devices/machine/mos6526.cpp')
-rw-r--r-- | src/devices/machine/mos6526.cpp | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/src/devices/machine/mos6526.cpp b/src/devices/machine/mos6526.cpp index e1f40b109c1..55368e33e86 100644 --- a/src/devices/machine/mos6526.cpp +++ b/src/devices/machine/mos6526.cpp @@ -902,7 +902,10 @@ uint8_t mos6526_device::read(offs_t offset) case ICR: data = (m_ir1 << 7) | m_icr; - if (machine().side_effects_disabled()) + // Do not reset irqs unless one is effectively issued. + // cfr. amigaocs_flop.xml barb2paln4 that polls for Timer B status + // until it expires at PC=7821c and other places. + if (machine().side_effects_disabled() || !m_icr) return data; m_icr_read = true; |