From aef4cb676cb5588b279ac22c095a6b91b06bc520 Mon Sep 17 00:00:00 2001 From: Mike Pavone Date: Sun, 28 Jun 2020 22:53:52 -0700 Subject: Enter debugger when a VDP data port read would cause a CPU lockup --- genesis.c | 2 +- vdp.c | 14 ++++++++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) diff --git a/genesis.c b/genesis.c index 7733f91..5cb010d 100644 --- a/genesis.c +++ b/genesis.c @@ -266,7 +266,7 @@ static void adjust_int_cycle(m68k_context * context, vdp_context * v_context) } context->target_cycle = context->int_cycle < context->sync_cycle ? context->int_cycle : context->sync_cycle; - if (context->should_return) { + if (context->should_return || gen->header.enter_debugger) { context->target_cycle = context->current_cycle; } else if (context->target_cycle < context->current_cycle) { //Changes to SR can result in an interrupt cycle that's in the past diff --git a/vdp.c b/vdp.c index 0ffc1a2..b0e412f 100644 --- a/vdp.c +++ b/vdp.c @@ -3953,6 +3953,20 @@ uint16_t vdp_data_port_read(vdp_context * context) } if (context->cd & 1) { warning("Read from VDP data port while writes are configured, CPU is now frozen. VDP Address: %X, CD: %X\n", context->address, context->cd); + context->system->enter_debugger = 1; + return context->prefetch; + } + switch (context->cd) + { + case VRAM_READ: + case VSRAM_READ: + case CRAM_READ: + case VRAM_READ8: + break; + default: + warning("Read from VDP data port with invalid source, CPU is now frozen. VDP Address: %X, CD: %X\n", context->address, context->cd); + context->system->enter_debugger = 1; + return context->prefetch; } while (!(context->flags & FLAG_READ_FETCHED)) { vdp_run_context_full(context, context->cycles + ((context->regs[REG_MODE_4] & BIT_H40) ? 16 : 20)); -- cgit v1.2.3