From 631aa3b0da0c330f275e8ce97b01af21d08df5c3 Mon Sep 17 00:00:00 2001
From: "K.Ohta" <whatisthis.sowhat@gmail.com>
Date: Sun, 23 Oct 2022 21:01:44 +0900
Subject: [PATCH] [VM][FMTOWNS][CDROM] I/O 04C0h : Adjust order of sequence at
 writing.

[VM][FMTOWNS][CDROM] I/O 04C4h : Re-enable parameter queue pointer.
[VM][FMTOWNS][CDROM] Update state version to 22.
---
 source/src/vm/fmtowns/cdrom.h         |  2 +-
 source/src/vm/fmtowns/cdrom/cdrom.cpp | 38 +++++++++++++++++------------------
 2 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/source/src/vm/fmtowns/cdrom.h b/source/src/vm/fmtowns/cdrom.h
index d359c7e0d..96eb13e95 100644
--- a/source/src/vm/fmtowns/cdrom.h
+++ b/source/src/vm/fmtowns/cdrom.h
@@ -367,7 +367,7 @@ protected:
 	uint8_t w_regs[16];
 	static const uint16_t crc_table[256];
 
-	int param_ptr;
+	uint8_t param_ptr;
 	bool command_entered;
 	bool param_filled;
 	uint8_t param_pre_queue[8];
diff --git a/source/src/vm/fmtowns/cdrom/cdrom.cpp b/source/src/vm/fmtowns/cdrom/cdrom.cpp
index 0829f1501..a86673e26 100644
--- a/source/src/vm/fmtowns/cdrom/cdrom.cpp
+++ b/source/src/vm/fmtowns/cdrom/cdrom.cpp
@@ -2764,23 +2764,24 @@ void TOWNS_CDROM::write_io8(uint32_t addr, uint32_t data)
 		// Note: Sync with TSUGARU.
 		// 20220127 K.O
 		//cdrom_debug_log(_T("PORT 04C0h <- %02X"), data);
-		mcu_intr_mask = ((data & 0x02) == 0) ? true : false;
-		dma_intr_mask = ((data & 0x01) == 0) ? true : false;
 		if((data & 0x80) != 0) {
-//			mcu_intr = false;
-//			if(!(dma_intr)) set_intrs_force(false, false, false);
-			set_mcu_intr(false);
+			mcu_intr = false;
+			if(!(dma_intr)) {
+				write_mcuint_signals(0); // Reset interrupt request to PIC.
+			}
 		}
 		if((data & 0x40) != 0) {
-//			dma_intr = false;
-//			if(!(mcu_intr)) set_intrs_force(false, false, false);
-			set_dma_intr(false);
+			dma_intr = false;
+			if(!(mcu_intr)) {
+				write_mcuint_signals(0); // Reset interrupt request to PIC.
+			}
 		}
 		if((data & 0x04) != 0) {
 			cdrom_debug_log(_T("RESET FROM CMDREG: 04C0h"));
 			reset_device();
-//			break;
 		}
+		mcu_intr_mask = ((data & 0x02) == 0) ? true : false;
+		dma_intr_mask = ((data & 0x01) == 0) ? true : false;
 		break;
 	case 0x02: // Command
 		//cdrom_debug_log(_T("PORT 04C2h <- %02X"), data);
@@ -2800,16 +2801,15 @@ void TOWNS_CDROM::write_io8(uint32_t addr, uint32_t data)
 		}
 		break;
 	case 0x04: // Param
-//		if(param_ptr >= 8) {
-//			param_ptr = 7;
-//		}
-		for(int xx = 1; xx < 8; xx++) {
-			param_queue[xx - 1] = param_queue[xx];
+		if(param_ptr >= 8) {
+			// Rotate queue
+			for(int xx = 0; xx < 7; xx++) {
+				param_queue[xx] = param_queue[xx + 1];
+			}
+			param_ptr = 7;
 		}
-//		}
-//		param_queue[param_ptr] = data;
-		param_queue[7] = data;
-//		param_ptr++;
+		param_queue[param_ptr] = data;
+		param_ptr++;
 		break;
 	case 0x06:
 		dma_transfer = ((data & 0x10) != 0) ? true : false;
@@ -2953,7 +2953,7 @@ bool TOWNS_CDROM::get_debug_regs_info(_TCHAR *buffer, size_t buffer_len)
 /*
  * Note: 20200428 K.O: DO NOT USE STATE SAVE, STILL don't implement completely yet.
  */
-#define STATE_VERSION	21
+#define STATE_VERSION	22
 
 bool TOWNS_CDROM::process_state(FILEIO* state_fio, bool loading)
 {
-- 
2.11.0