From d3ec40b392db348f3ab1273e90d68e32e7717a15 Mon Sep 17 00:00:00 2001
From: Vicki Pfau <vi@endrift.com>
Date: Sat, 30 Nov 2019 11:37:36 -0800
Subject: [PATCH] GB Memory: Support manual SRAM editing (fixes #1580)

---
 CHANGES         |  2 ++
 src/gb/memory.c | 10 +++++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/CHANGES b/CHANGES
index a451feeaa..c709f3851 100644
--- a/CHANGES
+++ b/CHANGES
@@ -97,6 +97,8 @@ Other fixes:
  - Core: Fix uninitialized memory issues with graphics caches
  - Vita: Fix analog controls (fixes mgba.io/i/1554)
  - Qt: Fix fast forward mute being reset (fixes mgba.io/i/1574)
+Misc:
+ - GB Memory: Support manual SRAM editing (fixes mgba.io/i/1580)
 
 0.8 beta 1: (2019-10-20)
 - Initial beta for 0.8
diff --git a/src/gb/memory.c b/src/gb/memory.c
index e5817cefe..e60fbde18 100644
--- a/src/gb/memory.c
+++ b/src/gb/memory.c
@@ -649,7 +649,15 @@ void GBPatch8(struct LR35902Core* cpu, uint16_t address, int8_t value, int8_t* o
 		break;
 	case GB_REGION_EXTERNAL_RAM:
 	case GB_REGION_EXTERNAL_RAM + 1:
-		mLOG(GB_MEM, STUB, "Unimplemented memory Patch8: 0x%08X", address);
+		if (memory->rtcAccess) {
+			memory->rtcRegs[memory->activeRtcReg] = value;
+		} else if (memory->sramAccess && memory->sram && memory->mbcType != GB_MBC2) {
+			// TODO: Remove sramAccess check?
+			memory->sramBank[address & (GB_SIZE_EXTERNAL_RAM - 1)] = value;
+		} else {
+			memory->mbcWrite(gb, address, value);
+		}
+		gb->sramDirty |= GB_SRAM_DIRT_NEW;
 		return;
 	case GB_REGION_WORKING_RAM_BANK0:
 	case GB_REGION_WORKING_RAM_BANK0 + 2: