From 4894e97dc567177638a5be45937a2456af27b7e4 Mon Sep 17 00:00:00 2001
From: TomW <TomW@localhost>
Date: Sat, 2 Nov 2013 19:38:59 +0000
Subject: [PATCH] Fixed some stupid serial issues - reading interrupt enable
 mask now works, and has an effect, and reading data when FIFO empty now
 returns last value instead of zero. Windows 9x setup now detects serial mouse
 correctly.

---
 src/mouse_serial.c |  1 -
 src/serial.c       | 27 +++++++++++++++------------
 src/serial.h       |  1 +
 3 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/src/mouse_serial.c b/src/mouse_serial.c
index 7f49749..4f75a83 100644
--- a/src/mouse_serial.c
+++ b/src/mouse_serial.c
@@ -58,7 +58,6 @@ void mousecallback()
                 serial.linestat|=1;
                 if (serial.mctrl&8) picint(0x10);
         }
-//        printf("Mouse callback\n");
 }
 
 void mouse_serial_init()
diff --git a/src/serial.c b/src/serial.c
index 69b3e7a..467ef1f 100644
--- a/src/serial.c
+++ b/src/serial.c
@@ -29,17 +29,20 @@ void serial_write_fifo(uint8_t dat)
         if (!(serial.linestat & 1))
         {
                 serial.linestat|=1;
-                if (serial.mctrl&8) picint(0x10);
+                if ((serial.mctrl & 8) && (serial.ier & 1))
+                        picint(0x10);
                 serial.iir=4;
         }
 }
 
 uint8_t serial_read_fifo()
 {
-        uint8_t temp = serial_fifo[serial_fifo_read];
         if (serial_fifo_read != serial_fifo_write)
-           serial_fifo_read = (serial_fifo_read + 1) & 0xFF;
-        return temp;
+        {
+                serial.dat = serial_fifo[serial_fifo_read];
+                serial_fifo_read = (serial_fifo_read + 1) & 0xFF;
+        }
+        return serial.dat;
 }
 
 void sendserial(uint8_t dat)
@@ -52,7 +55,7 @@ void sendserial(uint8_t dat)
 
 void serial_write(uint16_t addr, uint8_t val, void *priv)
 {
-//        printf("Write serial %03X %02X %04X:%04X\n",addr,val,CS,pc);
+//        pclog("Write serial %03X %02X %04X:%04X\n",addr,val,CS,pc);
         switch (addr&7)
         {
                 case 0:
@@ -84,7 +87,7 @@ void serial_write(uint16_t addr, uint8_t val, void *priv)
                 {
                         if (serial_rcr)
                            serial_rcr();
-//                        printf("RCR raised! sending M\n");
+//                        pclog("RCR raised! sending M\n");
                 }
                 serial.mctrl=val;
                 break;
@@ -94,7 +97,7 @@ void serial_write(uint16_t addr, uint8_t val, void *priv)
 uint8_t serial_read(uint16_t addr, void *priv)
 {
         uint8_t temp;
-//        printf("Read serial %03X %04X(%08X):%04X %i %i  ", addr, CS, cs, pc, mousedelay, ins);
+//        pclog("Read serial %03X %04X(%08X):%04X %i %i  ", addr, CS, cs, pc, mousedelay, ins);
         switch (addr&7)
         {
                 case 0:
@@ -112,7 +115,7 @@ uint8_t serial_read(uint16_t addr, void *priv)
                 break;
                 case 1:
                 if (serial.lcr&0x80 && !AMSTRADIO) temp = serial.dlab2;
-                else                               temp = 0;
+                else                               temp = serial.ier;
                 break;
                 case 2: temp=serial.iir; break;
                 case 3: temp=serial.lcr; break;
@@ -120,13 +123,13 @@ uint8_t serial_read(uint16_t addr, void *priv)
                 case 5: temp=serial.linestat; serial.linestat|=0x60; break;
                 default: temp=0;
         }
-//        printf("%02X\n",temp);
+//        pclog("%02X\n",temp);
         return temp;
 }
 
 void serial2_write(uint16_t addr, uint8_t val, void *priv)
 {
-//        printf("Write serial2 %03X %02X %04X:%04X\n",addr,val,cs>>4,pc);
+//        pclog("Write serial2 %03X %02X %04X:%04X\n",addr,val,cs>>4,pc);
         switch (addr&7)
         {
                 case 0:
@@ -161,7 +164,7 @@ void serial2_write(uint16_t addr, uint8_t val, void *priv)
 uint8_t serial2_read(uint16_t addr, void *priv)
 {
         uint8_t temp;
-//        printf("Read serial2 %03X %04X:%04X\n",addr,cs>>4,pc);
+//        pclog("Read serial2 %03X %04X:%04X\n",addr,cs>>4,pc);
         switch (addr&7)
         {
                 case 0:
@@ -180,7 +183,7 @@ uint8_t serial2_read(uint16_t addr, void *priv)
                 case 5: temp=serial2.linestat; break;
                 default: temp=0;
         }
-//        printf("%02X\n",temp);
+//        pclog("%02X\n",temp);
         return temp;
 }
 
diff --git a/src/serial.h b/src/serial.h
index bf0397d..058a15d 100644
--- a/src/serial.h
+++ b/src/serial.h
@@ -8,6 +8,7 @@ typedef struct
 {
         uint8_t linestat,thr,mctrl,rcr,iir,ier,lcr;
         uint8_t dlab1,dlab2;
+        uint8_t dat;
 } SERIAL;
 
 extern SERIAL serial,serial2;