From 53e926f4dd3187bb0fc5b1d45bfc026839f44d14 Mon Sep 17 00:00:00 2001 From: Michael Pavone Date: Thu, 2 Apr 2020 20:17:08 -0700 Subject: Reading from Z80 bus when Z80 is not bus requested should return open bus. Fixes regression in Metal Sonic Rebooted --- genesis.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'genesis.c') diff --git a/genesis.c b/genesis.c index 6b6ba13..c6dc8c0 100644 --- a/genesis.c +++ b/genesis.c @@ -888,7 +888,8 @@ static uint8_t io_read(uint32_t location, m68k_context * context) value = 0xFF; } } else { - value = 0xFF; + uint16_t word = get_open_bus_value(&gen->header); + value = location & 1 ? word : word >> 8; } } else { if (location < 0x10100) { -- cgit v1.2.3