RTC changes :

- Replace linux-time.c and win-time.c with universal rtc.c code
- Add RTC binary and 12-hour modes, century register, and alarm support
- Cleaned up nvr.c a bit
- Fix handling of update ended flag
- Add ability to disable host clock synchronisation
Changes from Battler and Mahod.

src/Makefile.am

@@ -21,8 +21,8 @@ codegen.c codegen_ops.c codegen_timing_486.c codegen_timing_686.c codegen_timing
 dac.c device.c disc.c disc_fdi.c disc_img.c disc_sector.c dma.c fdc.c fdc37c665.c fdd.c fdi2raw.c gameport.c \
 headland.c i430lx.c i430fx.c i430vx.c ide.c intel.c intel_flash.c io.c jim.c joystick_standard.c joystick_sw_pad.c \
 keyboard.c keyboard_amstrad.c keyboard_at.c keyboard_olim24.c keyboard_pcjr.c keyboard_xt.c \
-linux-time.c lpt.c mcr.c mem.c model.c mouse.c mouse_ps2.c mouse_serial.c neat.c nmi.c nvr.c \
-olivetti_m24.c opti.c pc.c pci.c pic.c piix.c pit.c ppi.c ps1.c rom.c scat.c serial.c sis496.c sound.c \
+lpt.c mcr.c mem.c model.c mouse.c mouse_ps2.c mouse_serial.c neat.c nmi.c nvr.c olivetti_m24.c \
+opti.c pc.c pci.c pic.c piix.c pit.c ppi.c ps1.c rom.c rtc.c scat.c serial.c sis496.c sound.c \
 sound_ad1848.c sound_adlib.c sound_adlibgold.c sound_cms.c sound_emu8k.c sound_gus.c \
 sound_mpu401_uart.c sound_opl.c sound_pas16.c sound_ps1.c sound_pssj.c sound_sb.c sound_sb_dsp.c sound_sn76489.c \
 sound_speaker.c sound_ssi2001.c sound_wss.c sound_ym7128.c soundopenal.c tandy_eeprom.c tandy_rom.c thread-pthread.c \

src/Makefile.mingw

@@ -8,7 +8,7 @@ OBJ = 386.o 386_dynarec.o 386_dynarec_ops.o 808x.o acer386sx.o ali1429.o amstrad
 	device.o disc.o disc_fdi.o disc_img.o disc_sector.o dma.o fdc.o fdc37c665.o fdd.o fdi2raw.o gameport.o headland.o i430lx.o i430fx.o \
 	i430vx.o ide.o intel.o intel_flash.o io.o jim.o joystick_standard.o joystick_sw_pad.o keyboard.o keyboard_amstrad.o keyboard_at.o \
 	keyboard_olim24.o keyboard_pcjr.o keyboard_xt.o lpt.o mcr.o mem.o model.o mouse.o mouse_ps2.o \
-	mouse_serial.o neat.o nmi.o nvr.o olivetti_m24.o opti.o pc.o pci.o pic.o piix.o pit.o ppi.o ps1.o rom.o \
+	mouse_serial.o neat.o nmi.o nvr.o olivetti_m24.o opti.o pc.o pci.o pic.o piix.o pit.o ppi.o ps1.o rom.o rtc.o \
 	scat.o serial.o sis496.o sound.o sound_ad1848.o sound_adlib.o sound_adlibgold.o sound_cms.o sound_dbopl.o \
 	sound_emu8k.o sound_gus.o sound_mpu401_uart.o sound_opl.o sound_pas16.o sound_ps1.o sound_pssj.o sound_resid.o \
 	sound_sb.o sound_sb_dsp.o sound_sn76489.o sound_speaker.o sound_ssi2001.o sound_wss.o \
@@ -20,7 +20,7 @@ OBJ = 386.o 386_dynarec.o 386_dynarec_ops.o 808x.o acer386sx.o ali1429.o amstrad
 	vid_svga_render.o vid_tandy.o vid_tandysl.o vid_tgui9440.o vid_tkd8001_ramdac.o vid_tvga.o vid_unk_ramdac.o \
 	vid_vga.o vid_voodoo.o video.o wd76c10.o win.o win-config.o win-d3d.o win-d3d-fs.o win-ddraw.o \
 	win-ddraw-fs.o win-deviceconfig.o win-hdconf.o win-joystick.o win-joystickconfig.o win-keyboard.o win-midi.o win-mouse.o \
-	win-status.o win-time.o win-video.o x86seg.o x87.o xtide.o pc.res
+	win-status.o win-video.o x86seg.o x87.o xtide.o pc.res
 DBOBJ = dbopl.o vid_cga_comp.o
 SIDOBJ = convolve.o convolve-sse.o envelope.o extfilt.o filter.o pot.o sid.o voice.o wave6581__ST.o wave6581_P_T.o wave6581_PS_.o wave6581_PST.o wave8580__ST.o wave8580_P_T.o wave8580_PS_.o wave8580_PST.o wave.o
 

src/Makefile.mingw64

@@ -8,7 +8,7 @@ OBJ = 386.o 386_dynarec.o 386_dynarec_ops.o 808x.o acer386sx.o ali1429.o amstrad
 	device.o disc.o disc_fdi.o disc_img.o disc_sector.o dma.o fdc.o fdc37c665.o fdd.o fdi2raw.o gameport.o headland.o i430lx.o i430fx.o \
 	i430vx.o ide.o intel.o intel_flash.o io.o jim.o joystick_standard.o joystick_sw_pad.o keyboard.o keyboard_amstrad.o keyboard_at.o \
 	keyboard_olim24.o keyboard_pcjr.o keyboard_xt.o lpt.o mcr.o mem.o model.o mouse.o mouse_ps2.o \
-	mouse_serial.o neat.o nmi.o nvr.o olivetti_m24.o opti.o pc.o pci.o pic.o piix.o pit.o ppi.o ps1.o rom.o \
+	mouse_serial.o neat.o nmi.o nvr.o olivetti_m24.o opti.o pc.o pci.o pic.o piix.o pit.o ppi.o ps1.o rom.o rtc.o \
 	scat.o serial.o sis496.o sound.o sound_ad1848.o sound_adlib.o sound_adlibgold.o sound_cms.o sound_dbopl.o \
 	sound_emu8k.o sound_gus.o sound_mpu401_uart.o sound_opl.o sound_pas16.o sound_ps1.o sound_pssj.o sound_resid.o \
 	sound_sb.o sound_sb_dsp.o sound_sn76489.o sound_speaker.o sound_ssi2001.o sound_wss.o sound_ym7128.o \
@@ -20,7 +20,7 @@ OBJ = 386.o 386_dynarec.o 386_dynarec_ops.o 808x.o acer386sx.o ali1429.o amstrad
 	vid_svga_render.o vid_tandy.o vid_tandysl.o vid_tgui9440.o vid_tkd8001_ramdac.o vid_tvga.o vid_unk_ramdac.o \
 	vid_vga.o vid_voodoo.o video.o wd76c10.o win.o win-config.o win-d3d.o win-d3d-fs.o win-ddraw.o \
 	win-ddraw-fs.o win-deviceconfig.o win-hdconf.o win-joystick.o win-joystickconfig.o win-keyboard.o win-midi.o win-mouse.o \
-	win-status.o win-time.o win-video.o x86seg.o x87.o xtide.o pc.res
+	win-status.o win-video.o x86seg.o x87.o xtide.o pc.res
 DBOBJ = dbopl.o vid_cga_comp.o
 SIDOBJ = convolve.o convolve-sse.o envelope.o extfilt.o filter.o pot.o sid.o voice.o wave6581__ST.o wave6581_P_T.o wave6581_PS_.o wave6581_PST.o wave8580__ST.o wave8580_P_T.o wave8580_PS_.o wave8580_PST.o wave.o
 

src/linux-time.c

@@ -1,48 +0,0 @@
-#include <sys/time.h>
-#include <time.h>
-#include "ibm.h"
-#include "nvr.h"
-
-void time_get(char *nvrram)
-{
-        int c,d;
-        uint8_t baknvr[10];
-	time_t cur_time;
-	struct tm cur_time_tm;
-
-        memcpy(baknvr,nvrram,10);
-
-	cur_time = time(NULL);
-	localtime_r(&cur_time, &cur_time_tm);
-
-        d = cur_time_tm.tm_sec % 10;
-        c = cur_time_tm.tm_sec / 10;
-        nvrram[0] = d | (c << 4);
-        d = cur_time_tm.tm_min % 10;
-        c = cur_time_tm.tm_min / 10;
-        nvrram[2] = d | (c << 4);
-        d = cur_time_tm.tm_hour % 10;
-        c = cur_time_tm.tm_hour / 10;
-        nvrram[4] = d | (c << 4);
-        d = cur_time_tm.tm_wday % 10;
-        c = cur_time_tm.tm_wday / 10;
-        nvrram[6] = d | (c << 4);
-        d = cur_time_tm.tm_mday % 10;
-        c = cur_time_tm.tm_mday / 10;
-        nvrram[7] = d | (c << 4);
-        d = cur_time_tm.tm_mon % 10;
-        c = cur_time_tm.tm_mon / 10;
-        nvrram[8] = d | (c << 4);
-        d = cur_time_tm.tm_year % 10;
-        c = (cur_time_tm.tm_year / 10) % 10;
-        nvrram[9] = d | (c << 4);
-        if (baknvr[0] != nvrram[0] ||
-            baknvr[2] != nvrram[2] ||
-            baknvr[4] != nvrram[4] ||
-            baknvr[6] != nvrram[6] ||
-            baknvr[7] != nvrram[7] ||
-            baknvr[8] != nvrram[8] ||
-            baknvr[9] != nvrram[9])
-		nvrram[0xA] |= 0x80;
-}
-

src/nvr.c

@@ -4,6 +4,7 @@
 #include "nvr.h"
 #include "pic.h"
 #include "timer.h"
+#include "rtc.h"
 
 int oldromset;
 int nvrmask=63;
@@ -23,7 +24,7 @@ void nvr_recalc()
 {
         int c;
         int newrtctime;
-        c=1<<((nvrram[0xA]&0xF)-1);
+        c = 1 << ((nvrram[RTC_REGA] & RTC_RS) - 1);
         newrtctime=(int)(RTCCONST * c * (1 << TIMER_SHIFT));
         if (rtctime>newrtctime) rtctime=newrtctime;
 }
@@ -31,64 +32,136 @@ void nvr_recalc()
 void nvr_rtc(void *p)
 {
         int c;
-        if (!(nvrram[0xA]&0xF))
+        if (!(nvrram[RTC_REGA] & RTC_RS))
         {
                 rtctime=0x7fffffff;
                 return;
         }
-        c=1<<((nvrram[0xA]&0xF)-1);
+        c = 1 << ((nvrram[RTC_REGA] & RTC_RS) - 1);
         rtctime += (int)(RTCCONST * c * (1 << TIMER_SHIFT));
 //        pclog("RTCtime now %f\n",rtctime);
-        nvrram[0xC] |= 0x40;
-        if (nvrram[0xB]&0x40)
+        nvrram[RTC_REGC] |= RTC_PF;
+        if (nvrram[RTC_REGB] & RTC_PIE)
         {
-                nvrram[0xC]|=0x80;
+                nvrram[RTC_REGC] |= RTC_IRQF;
                 if (AMSTRAD) picint(2);
                 else         picint(0x100);
 //                pclog("RTC int\n");
         }
 }
 
+int nvr_update_status = 0;
+
+#define ALARM_DONTCARE	0xc0
+
+int nvr_check_alarm(int nvraddr)
+{
+        return (nvrram[nvraddr + 1] == nvrram[nvraddr] || (nvrram[nvraddr + 1] & ALARM_DONTCARE) == ALARM_DONTCARE);
+}
+
+int nvr_update_end_count = 0;
+
+void nvr_update_end(void *p)
+{
+        if (!(nvrram[RTC_REGB] & RTC_SET))
+        {
+                getnvrtime();
+                /* Clear update status. */
+                nvr_update_status = 0;
+
+                if (nvr_check_alarm(RTC_SECONDS) && nvr_check_alarm(RTC_MINUTES) && nvr_check_alarm(RTC_HOURS))
+                {
+                        nvrram[RTC_REGC] |= RTC_AF;
+                        if (nvrram[RTC_REGB] & RTC_AIE)
+                        {
+                                nvrram[RTC_REGC] |= RTC_IRQF;
+                                if (AMSTRAD) picint(2);
+                                else         picint(0x100);
+                        }
+                }
+
+                /* The flag and interrupt should be issued on update ended, not started. */
+                nvrram[RTC_REGC] |= RTC_UF;
+                if (nvrram[RTC_REGB] & RTC_UIE)
+                {
+                        nvrram[RTC_REGC] |= RTC_IRQF;
+                        if (AMSTRAD) picint(2);
+                        else         picint(0x100);
+                }
+        }
+        
+//                pclog("RTC onesec\n");
+
+        nvr_update_end_count = 0;
+}
+
 void nvr_onesec(void *p)
 {
         nvr_onesec_cnt++;
         if (nvr_onesec_cnt >= 100)
         {
-                nvr_onesec_cnt = 0;
-                nvrram[0xC] |= 0x10;
-                if (nvrram[0xB] & 0x10)
+                if (!(nvrram[RTC_REGB] & RTC_SET))
                 {
-                        nvrram[0xC] |= 0x80;
-                        if (AMSTRAD) picint(2);
-                        else         picint(0x100);
+                        nvr_update_status = RTC_UIP;
+                        /* If sync is disabled, move internal clock ahead by 1 second. */
+                        if (!enable_sync)
+                                rtc_tick();
+
+                        nvr_update_end_count = (int)((244.0 + 1984.0) * TIMER_USEC);
                 }
-//                pclog("RTC onesec\n");
         }
         nvr_onesec_time += (int)(10000 * TIMER_USEC);
 }
 
 void writenvr(uint16_t addr, uint8_t val, void *priv)
 {
-        int c;
+        int c, old;
 //        printf("Write NVR %03X %02X %02X %04X:%04X %i\n",addr,nvraddr,val,cs>>4,pc,ins);
         if (addr&1)
         {
+                if (nvraddr==RTC_REGC || nvraddr==RTC_REGD)
+                        return; /* Registers C and D are read-only. There's no reason to continue. */
 //                if (nvraddr == 0x33) pclog("NVRWRITE33 %02X %04X:%04X %i\n",val,CS,pc,ins);
-                if (nvraddr >= 0xe && nvrram[nvraddr] != val) 
+                if (nvraddr > RTC_REGD && nvrram[nvraddr] != val)
                    nvr_dosave = 1;
-                if (nvraddr!=0xC && nvraddr!=0xD) nvrram[nvraddr]=val;
                 
-                if (nvraddr==0xA)
+		old = nvrram[nvraddr];
+                nvrram[nvraddr]=val;
+
+                if (nvraddr == RTC_REGA)
                 {
 //                        pclog("NVR rate %i\n",val&0xF);
-                        if (val&0xF)
+                        if (val & RTC_RS)
                         {
-                                c=1<<((val&0xF)-1);
+                                c = 1 << ((val & RTC_RS) - 1);
                                 rtctime += (int)(RTCCONST * c * (1 << TIMER_SHIFT));
                         }
                         else
                            rtctime = 0x7fffffff;
                 }
+		else
+		{
+                        if (nvraddr == RTC_REGB)
+                        {
+                                if (((old ^ val) & RTC_SET) && (val & RTC_SET))
+                                {
+                                        nvrram[RTC_REGA] &= ~RTC_UIP;             /* This has to be done according to the datasheet. */
+                                        nvrram[RTC_REGB] &= ~RTC_UIE;             /* This also has to happen per the specification. */
+                                }
+                        }
+
+                        if ((nvraddr < RTC_REGA) || (nvraddr == RTC_CENTURY))
+                        {
+                                if ((nvraddr != 1) && (nvraddr != 3) && (nvraddr != 5))
+                                {
+                                        if ((old != val) && !enable_sync)
+                                        {
+                                                time_update(nvrram, nvraddr);
+                                                nvr_dosave = 1;
+                                        }
+                                }
+                        }
+                }
         }
         else        nvraddr=val&nvrmask;
 }
@@ -99,20 +172,16 @@ uint8_t readnvr(uint16_t addr, void *priv)
 //        printf("Read NVR %03X %02X %02X %04X:%04X\n",addr,nvraddr,nvrram[nvraddr],cs>>4,pc);
         if (addr&1)
         {
-                if (nvraddr<=0xA) getnvrtime();
-                if (nvraddr==0xD) nvrram[0xD]|=0x80;
-                if (nvraddr==0xA)
-                {
-                        temp=nvrram[0xA];
-                        nvrram[0xA]&=~0x80;
-                        return temp;
-                }
-                if (nvraddr==0xC)
+                if (nvraddr == RTC_REGA)
+                        return ((nvrram[RTC_REGA] & 0x7F) | nvr_update_status);
+                if (nvraddr == RTC_REGD)
+                        nvrram[RTC_REGD] |= RTC_VRT;
+                if (nvraddr == RTC_REGC)
                 {
                         if (AMSTRAD) picintc(2);
                         else         picintc(0x100);
-                        temp=nvrram[0xC];
-                        nvrram[0xC]=0;
+                        temp = nvrram[RTC_REGC];
+                        nvrram[RTC_REGC] = 0;
                         return temp;
                 }
 //                if (AMIBIOS && nvraddr==0x36) return 0;
@@ -161,13 +230,22 @@ void loadnvr()
         if (!f)
         {
                 memset(nvrram,0xFF,128);
+                if (!enable_sync)
+                {
+                        nvrram[RTC_SECONDS] = nvrram[RTC_MINUTES] = nvrram[RTC_HOURS] = 0;
+                        nvrram[RTC_DOM] = nvrram[RTC_MONTH] = 1;
+                        nvrram[RTC_YEAR] = BCD(80);
+                        nvrram[RTC_CENTURY] = BCD(19);
+                        nvrram[RTC_REGB] = RTC_2412;
+                }
                 return;
         }
         fread(nvrram,128,1,f);
+        if (!enable_sync)  time_update(nvrram, 0xFF);        /* Update the internal clock state based on the NVR registers. */
         fclose(f);
-        nvrram[0xA]=6;
-        nvrram[0xB]=0;
-        c=1<<((6&0xF)-1);
+        nvrram[RTC_REGA] = 6;
+        nvrram[RTC_REGB] = RTC_2412;
+        c = 1 << ((nvrram[RTC_REGA] & RTC_RS) - 1);
         rtctime += (int)(RTCCONST * c * (1 << TIMER_SHIFT));
 }
 void savenvr()
@@ -212,4 +290,6 @@ void nvr_init()
         io_sethandler(0x0070, 0x0002, readnvr, NULL, NULL, writenvr, NULL, NULL,  NULL);
         timer_add(nvr_rtc, &rtctime, TIMER_ALWAYS_ENABLED, NULL);
         timer_add(nvr_onesec, &nvr_onesec_time, TIMER_ALWAYS_ENABLED, NULL);
+        timer_add(nvr_update_end, &nvr_update_end_count, &nvr_update_end_count, NULL);
+
 }

src/nvr.h

@@ -1,5 +1,7 @@
 void nvr_init();
 
+extern int enable_sync;
+
 extern int nvr_dosave;
 
 void time_get(char *nvrram);

src/pc.c

@@ -97,6 +97,7 @@ void fatal(const char *format, ...)
    va_end(ap);
    fputs(buf,pclogf);
    fflush(pclogf);
+   savenvr();
    dumppic();
    dumpregs();
    exit(-1);
@@ -679,6 +680,8 @@ void loadconfig(char *fn)
                         }
                 }
         }
+
+        enable_sync = config_get_int(NULL, "enable_sync", 1);
 }
 
 void saveconfig()
@@ -764,6 +767,8 @@ void saveconfig()
                         }
                 }
         }
+        
+        config_set_int(NULL, "enable_sync", enable_sync);
 
         config_save(config_file_default);
 }

src/pc.rc

@@ -57,13 +57,13 @@ BEGIN
         END
 END
 
-ConfigureDlg DIALOGEX 0, 0, 232+40, 292+40+40
+ConfigureDlg DIALOGEX 0, 0, 232+40, 308+40+40
 STYLE DS_SETFONT | DS_MODALFRAME | DS_FIXEDSYS | WS_POPUP | WS_CAPTION | WS_SYSMENU
 CAPTION "Configure PCem"
 FONT 8, "MS Sans Serif"
 BEGIN
-    DEFPUSHBUTTON   "OK",IDOK,64,308+40,50,14, WS_TABSTOP
-    PUSHBUTTON      "Cancel",IDCANCEL,128,308+40,50,14, WS_TABSTOP
+    DEFPUSHBUTTON   "OK",IDOK,64,324+40,50,14, WS_TABSTOP
+    PUSHBUTTON      "Cancel",IDCANCEL,128,324+40,50,14, WS_TABSTOP
     COMBOBOX        IDC_COMBO1,62,16,157,120,CBS_DROPDOWN | WS_VSCROLL | WS_TABSTOP
     COMBOBOX        IDC_COMBOVID,62,36,157,120,CBS_DROPDOWN | WS_VSCROLL | WS_TABSTOP
     PUSHBUTTON      "Configure", IDC_CONFIGUREVID, 224, 36, 40, 14, WS_TABSTOP
@@ -81,8 +81,9 @@ BEGIN
     CONTROL         "Gravis Ultrasound",IDC_CHECKGUS,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,14,288,118,10    
     CONTROL         "Innovation SSI-2001",IDC_CHECKSSI,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,14,304,118,10
     CONTROL         "Composite CGA",IDC_CHECK4,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,14,320,118,10
-    CONTROL         "Voodoo Graphics",IDC_CHECKVOODOO,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,14,336,118,10
-    PUSHBUTTON      "Configure", IDC_CONFIGUREVOODOO, 224, 336, 40, 14, WS_TABSTOP
+    CONTROL         "Synchronise time to host clock",IDC_CHECKSYNC,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,14,336,118,10
+    CONTROL         "Voodoo Graphics",IDC_CHECKVOODOO,"Button",BS_AUTOCHECKBOX | WS_TABSTOP,14,352,118,10
+    PUSHBUTTON      "Configure", IDC_CONFIGUREVOODOO, 224, 352, 40, 14, WS_TABSTOP
     LTEXT           "Machine :",IDC_STATIC,15,16,40,10
     LTEXT           "Video :",IDC_STATIC,15,36,34,10
     LTEXT           "CPU type :",IDC_STATIC,15,56,34,10

src/resources.h

@@ -47,6 +47,7 @@
 #define IDC_CHECKSSI 1015
 #define IDC_CHECKVOODOO 1016
 #define IDC_CHECKDYNAREC 1017
+#define IDC_CHECKSYNC 1018
 #define IDC_STATIC 1020
 #define IDC_EDIT1  1030
 #define IDC_EDIT2  1031

src/rtc.c

@@ -0,0 +1,244 @@
+/* Emulation of:
+   Dallas Semiconductor DS12C887 Real Time Clock
+
+   http://datasheets.maximintegrated.com/en/ds/DS12885-DS12C887A.pdf
+
+   http://dev-docs.atariforge.org/files/MC146818A_RTC_1984.pdf  
+ */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "nvr.h"
+#include "rtc.h"
+
+int enable_sync;
+
+struct
+{
+        int sec;
+        int min;
+        int hour;
+        int mday;
+        int mon;
+        int year;
+} internal_clock;
+
+/* When the RTC was last updated */
+static time_t rtc_set_time = 0;
+
+/* Table for days in each month */
+static int rtc_days_in_month[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
+
+/* Called to determine whether the year is leap or not */
+static int rtc_is_leap(int org_year)
+{
+        if (org_year % 400 == 0)  return 1;
+        if (org_year % 100 == 0)  return 0;
+        if (org_year % 4 == 0)  return 1;
+        return 0;
+}
+
+/* Called to determine the days in the current month */
+static int rtc_get_days(int org_month, int org_year)
+{
+        if (org_month != 2)
+                return rtc_days_in_month[org_month];
+        else
+                return rtc_is_leap(org_year) ? 29 : 28;
+}
+
+/* Called when the internal clock gets updated */
+static void rtc_recalc()
+{
+        if (internal_clock.sec == 60)
+        {
+                internal_clock.sec = 0;
+                internal_clock.min++;
+        }
+        if (internal_clock.min == 60)
+        {
+                internal_clock.min = 0;
+                internal_clock.hour++;
+        }
+        if (internal_clock.hour == 24)
+        {
+                internal_clock.hour = 0;
+                internal_clock.mday++;
+        }
+        if (internal_clock.mday == (rtc_get_days(internal_clock.mon, internal_clock.year) + 1))
+        {
+                internal_clock.mday = 1;
+                internal_clock.mon++;
+        }
+        if (internal_clock.mon == 13)
+        {
+                internal_clock.mon = 1;
+                internal_clock.year++;
+        }
+}
+
+/* Called when ticking the second */
+void rtc_tick()
+{
+        internal_clock.sec++;
+        rtc_recalc();
+}
+
+/* Called when modifying the NVR registers */
+void time_update(char *nvrram, int reg)
+{
+        int temp;
+
+        switch(reg)
+        {
+                case RTC_SECONDS:
+                internal_clock.sec = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_SECONDS] : DCB(nvrram[RTC_SECONDS]);
+                break;
+                case RTC_MINUTES:
+                internal_clock.min = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_MINUTES] : DCB(nvrram[RTC_MINUTES]);
+                break;
+                case RTC_HOURS:
+                temp = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_HOURS] : DCB(nvrram[RTC_HOURS]);
+
+                if (nvrram[RTC_REGB] & RTC_2412)
+                        internal_clock.hour = temp;
+                else
+                        internal_clock.hour = ((temp & ~RTC_AMPM) % 12) + ((temp & RTC_AMPM) ? 12 : 0);
+                break;
+                case RTC_DOM:
+                internal_clock.mday = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_DOM] : DCB(nvrram[RTC_DOM]);
+                break;
+                case RTC_MONTH:
+                internal_clock.mon = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_MONTH] : DCB(nvrram[RTC_MONTH]);
+                break;
+                case RTC_YEAR:
+                internal_clock.year = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_YEAR] : DCB(nvrram[RTC_YEAR]);
+                internal_clock.year += (nvrram[RTC_REGB] & RTC_DM) ? 1900 : (DCB(nvrram[RTC_CENTURY]) * 100);
+                break;
+                case RTC_CENTURY:
+                if (nvrram[RTC_REGB] & RTC_DM)
+                        return;
+                internal_clock.year %= 100;
+                internal_clock.year += (DCB(nvrram[RTC_CENTURY]) * 100);
+                break;
+                case 0xFF:        /* Load the entire internal clock state from the NVR. */
+                internal_clock.sec = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_SECONDS] : DCB(nvrram[RTC_SECONDS]);
+                internal_clock.min = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_MINUTES] : DCB(nvrram[RTC_MINUTES]);
+
+                temp = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_HOURS] : DCB(nvrram[RTC_HOURS]);
+
+                if (nvrram[RTC_REGB] & RTC_2412)
+                        internal_clock.hour = temp;
+                else
+                        internal_clock.hour = ((temp & ~RTC_AMPM) % 12) + ((temp & RTC_AMPM) ? 12 : 0);
+
+                internal_clock.mday = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_DOM] : DCB(nvrram[RTC_DOM]);
+                internal_clock.mon = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_MONTH] : DCB(nvrram[RTC_MONTH]);
+                internal_clock.year = (nvrram[RTC_REGB] & RTC_DM) ? nvrram[RTC_YEAR] : DCB(nvrram[RTC_YEAR]);
+                internal_clock.year += (nvrram[RTC_REGB] & RTC_DM) ? 1900 : (DCB(nvrram[RTC_CENTURY]) * 100);
+                break;
+        }
+}
+
+/* Called to obtain the current day of the week based on the internal clock */
+static int time_week_day()
+{
+        int day_of_month = internal_clock.mday;
+        int month2 = internal_clock.mon;
+        int year2 = internal_clock.year % 100;
+        int century = ((internal_clock.year - year2) / 100) % 4;
+        int sum = day_of_month + month2 + year2 + century;
+        /* (Sum mod 7) gives 0 for Saturday, we need it for Sunday, so +6 for Saturday to get 6 and Sunday 0 */
+        int raw_wd = ((sum + 6) % 7);
+        return raw_wd;
+}
+
+/* Called to get time into the internal clock */
+static void time_internal(struct tm **time_var)
+{
+        if (*time_var == NULL)
+                *time_var = (struct tm *)malloc(sizeof(struct tm));
+
+        (*time_var)->tm_sec = internal_clock.sec;
+        (*time_var)->tm_min = internal_clock.min;
+        (*time_var)->tm_hour = internal_clock.hour;
+        (*time_var)->tm_wday = time_week_day();
+        (*time_var)->tm_mday = internal_clock.mday;
+        (*time_var)->tm_mon = internal_clock.mon - 1;
+        (*time_var)->tm_year = internal_clock.year - 1900;
+}
+
+static time_t cur_time;
+static struct tm *cur_time_tm;
+
+/* Periodic RTC update function
+   See also: nvr_onesec() in nvr.c
+ */
+void time_get(char *nvrram)
+{
+        int dow, mon, year;
+
+        if (enable_sync)
+        {
+		time(&cur_time);
+
+                /* Mingw doesn't support localtime_r */
+                #if __MINGW32__
+                cur_time_tm = localtime(&cur_time);
+                #else
+                #if __MINGW64__
+                cur_time_tm = localtime(&cur_time);
+                #else
+                localtime_r(&cur_time, &cur_time_tm);
+                #endif
+                #endif
+        }
+        else
+        {
+                time_internal(&cur_time_tm);
+        }
+
+        if (nvrram[RTC_REGB] & RTC_DM)
+        {
+                nvrram[RTC_SECONDS] = cur_time_tm->tm_sec;
+                nvrram[RTC_MINUTES] = cur_time_tm->tm_min;
+                nvrram[RTC_DOW]     = cur_time_tm->tm_wday + 1;
+                nvrram[RTC_DOM]     = cur_time_tm->tm_mday;
+                nvrram[RTC_MONTH]   = cur_time_tm->tm_mon + 1;
+                nvrram[RTC_YEAR]    = cur_time_tm->tm_year % 100;
+
+                if (nvrram[RTC_REGB] & RTC_2412)
+                {
+                        nvrram[RTC_HOURS] = cur_time_tm->tm_hour;
+                }
+                else
+                {
+                        nvrram[RTC_HOURS] = (cur_time_tm->tm_hour % 12) ? (cur_time_tm->tm_hour % 12) : 12;
+                        if (cur_time_tm->tm_hour > 11)
+                                nvrram[RTC_HOURS] |= RTC_AMPM;
+                }
+        }
+        else
+        {
+                nvrram[RTC_SECONDS] = BCD(cur_time_tm->tm_sec);
+                nvrram[RTC_MINUTES] = BCD(cur_time_tm->tm_min);
+                nvrram[RTC_DOW]     = BCD(cur_time_tm->tm_wday + 1);
+                nvrram[RTC_DOM]     = BCD(cur_time_tm->tm_mday);
+                nvrram[RTC_MONTH]   = BCD(cur_time_tm->tm_mon + 1);
+                nvrram[RTC_YEAR]    = BCD(cur_time_tm->tm_year % 100);
+
+                if (nvrram[RTC_REGB] & RTC_2412)
+                {
+                        nvrram[RTC_HOURS] = BCD(cur_time_tm->tm_hour);
+                }
+                else
+                {
+                        nvrram[RTC_HOURS] = (cur_time_tm->tm_hour % 12) ? BCD(cur_time_tm->tm_hour % 12) : BCD(12);
+                        if (cur_time_tm->tm_hour > 11)
+                                nvrram[RTC_HOURS] |= RTC_AMPM;
+                }
+        }
+}

src/rtc.h

@@ -0,0 +1,172 @@
+#define BCD(X) (((X) % 10) | (((X) / 10) << 4))
+#define DCB(X) ((((X) & 0xF0) >> 4) * 10 + ((X) & 0x0F))
+
+enum RTC_ADDR
+{
+        RTC_SECONDS,
+        RTC_ALARMSECONDS,
+        RTC_MINUTES,
+        RTC_ALARMMINUTES,
+        RTC_HOURS,
+        RTC_ALARMHOURS,
+        RTC_DOW,
+        RTC_DOM,
+        RTC_MONTH,
+        RTC_YEAR,
+        RTC_REGA,
+        RTC_REGB,
+        RTC_REGC,
+        RTC_REGD
+};
+
+/*      The century register at location 32h is a BCD register designed to automatically load the BCD value 20 as the year register changes from 99 to 00.
+        The MSB of this register is not affected when the load of 20 occurs, and remains at the value written by the user. */
+#define RTC_CENTURY 0x32
+
+/*      When the 12-hour format is selected, the higher-order bit of the hours byte represents PM when it is logic 1. */
+#define RTC_AMPM 0b10000000
+
+/*      Register A bitflags */
+enum RTC_RA_BITS 
+{
+/*      Rate Selector (RS0)
+
+        These four rate-selection bits select one of the 13 taps on the 15-stage divider or disable the divider output.
+        The tap selected can be used to generate an output square wave (SQW pin) and/or a periodic interrupt.
+        The user can do one of the following:
+        - Enable the interrupt with the PIE bit;
+        - Enable the SQW output pin with the SQWE bit;
+        - Enable both at the same time and the same rate; or
+        - Enable neither.
+
+        Table 3 lists the periodic interrupt rates and the square wave frequencies that can be chosen with the RS bits.
+        These four read/write bits are not affected by !RESET. */
+        RTC_RS = 0b1111,
+/*      DV0
+
+        These three bits are used to turn the oscillator on or off and to reset the countdown chain.
+        A pattern of 010 is the only combination of bits that turn the oscillator on and allow the RTC to keep time.
+        A pattern of 11x enables the oscillator but holds the countdown chain in reset.
+        The next update occurs at 500ms after a pattern of 010 is written to DV0, DV1, and DV2. */
+        RTC_DV0 = 0b1110000,
+/*      Update-In-Progress (UIP)
+
+        This bit is a status flag that can be monitored. When the UIP bit is a 1, the update transfer occurs soon.
+        When UIP is a 0, the update transfer does not occur for at least 244us.
+        The time, calendar, and alarm information in RAM is fully available for access when the UIP bit is 0.
+        The UIP bit is read-only and is not affected by !RESET.
+        Writing the SET bit in Register B to a 1 inhibits any update transfer and clears the UIP status bit. */
+        RTC_UIP = 0b10000000
+};
+
+/*      Register B bitflags */
+enum RTC_RB_BITS 
+{
+/*      Daylight Saving Enable (DSE)
+
+        This bit is a read/write bit that enables two daylight saving adjustments when DSE is set to 1.
+        On the first Sunday in April (or the last Sunday in April in the MC146818A), the time increments from 1:59:59 AM to 3:00:00 AM.
+        On the last Sunday in October when the time first reaches 1:59:59 AM, it changes to 1:00:00 AM.
+        When DSE is enabled, the internal logic test for the first/last Sunday condition at midnight.
+        If the DSE bit is not set when the test occurs, the daylight saving function does not operate correctly.
+        These adjustments do not occur when the DSE bit is 0. This bit is not affected by internal functions or !RESET. */
+        RTC_DSE = 0b1,
+/*      24/12
+
+        The 24/12 control bit establishes the format of the hours byte. A 1 indicates the 24-hour mode and a 0 indicates the 12-hour mode.
+        This bit is read/write and is not affected by internal functions or !RESET. */
+        RTC_2412 = 0b10,
+/*      Data Mode (DM)
+
+        This bit indicates whether time and calendar information is in binary or BCD format.
+        The DM bit is set by the program to the appropriate format and can be read as required.
+        This bit is not modified by internal functions or !RESET. A 1 in DM signifies binary data, while a 0 in DM specifies BCD data. */
+        RTC_DM = 0b100,
+/*      Square-Wave Enable (SQWE)
+
+        When this bit is set to 1, a square-wave signal at the frequency set by the rate-selection bits RS3-RS0 is driven out on the SQW pin.
+        When the SQWE bit is set to 0, the SQW pin is held low. SQWE is a read/write bit and is cleared by !RESET.
+        SQWE is low if disabled, and is high impedance when VCC is below VPF. SQWE is cleared to 0 on !RESET. */
+        RTC_SQWE = 0b1000,
+/*      Update-Ended Interrupt Enable (UIE)
+
+        This bit is a read/write bit that enables the update-end flag (UF) bit in Register C to assert !IRQ.
+        The !RESET pin going low or the SET bit going high clears the UIE bit.
+        The internal functions of the device do not affect the UIE bit, but is cleared to 0 on !RESET. */
+        RTC_UIE = 0b10000,
+/*      Alarm Interrupt Enable (AIE)
+
+        This bit is a read/write bit that, when set to 1, permits the alarm flag (AF) bit in Register C to assert !IRQ.
+        An alarm interrupt occurs for each second that the three time bytes equal the three alarm bytes, including a don't-care alarm code of binary 11XXXXXX.
+        The AF bit does not initiate the !IRQ signal when the AIE bit is set to 0.
+        The internal functions of the device do not affect the AIE bit, but is cleared to 0 on !RESET. */
+        RTC_AIE = 0b100000,
+/*      Periodic Interrupt Enable (PIE)
+
+        The PIE bit is a read/write bit that allows the periodic interrupt flag (PF) bit in Register C to drive the !IRQ pin low.
+        When the PIE bit is set to 1, periodic interrupts are generated by driving the !IRQ pin low at a rate specified by the RS3-RS0 bits of Register A.
+        A 0 in the PIE bit blocks the !IRQ output from being driven by a periodic interrupt, but the PF bit is still set at the periodic rate.
+        PIE is not modified by any internal device functions, but is cleared to 0 on !RESET. */
+        RTC_PIE = 0b1000000,
+/*      SET
+
+        When the SET bit is 0, the update transfer functions normally by advancing the counts once per second.
+        When the SET bit is written to 1, any update transfer is inhibited, and the program can initialize the time and calendar bytes without an update
+        occurring in the midst of initializing. Read cycles can be executed in a similar manner. SET is a read/write bit and is not affected by !RESET or
+        internal functions of the device. */
+        RTC_SET = 0b10000000
+};
+
+/*      Register C bitflags */
+enum RTC_RC_BITS 
+{
+/*      Unused
+
+        These bits are unused in Register C. These bits always read 0 and cannot be written. */
+        RTC_RC = 0b1111,
+/*      Update-Ended Interrupt Flag (UF)
+
+        This bit is set after each update cycle. When the UIE bit is set to 1, the 1 in UF causes the IRQF bit to be a 1, which asserts the !IRQ pin.
+        This bit can be cleared by reading Register C or with a !RESET. */
+        RTC_UF = 0b10000,
+/*      Alarm Interrupt Flag (AF)
+
+        A 1 in the AF bit indicates that the current time has matched the alarm time.
+        If the AIE bit is also 1, the !IRQ pin goes low and a 1 appears in the IRQF bit. This bit can be cleared by reading Register C or with a !RESET. */
+        RTC_AF = 0b100000,
+/*      Periodic Interrupt Flag (PF)
+
+        This bit is read-only and is set to 1 when an edge is detected on the selected tap of the divider chain.
+        The RS3 through RS0 bits establish the periodic rate. PF is set to 1 independent of the state of the PIE bit.
+        When both PF and PIE are 1s, the !IRQ signal is active and sets the IRQF bit. This bit can be cleared by reading Register C or with a !RESET. */
+        RTC_PF = 0b1000000,
+/*      Interrupt Request Flag (IRQF)
+
+        The interrupt request flag (IRQF) is set to a 1 when one or more of the following are true:
+        - PF == PIE == 1
+        - AF == AIE == 1
+        - UF == UIE == 1
+
+        Any time the IRQF bit is a 1, the !IRQ pin is driven low.
+        All flag bits are cleared after Register C is read by the program or when the !RESET pin is low. */
+        RTC_IRQF = 0b10000000
+};
+
+/*      Register D bitflags */
+enum RTC_RD_BITS 
+{
+/*      Unused
+
+        The remaining bits of Register D are not usable. They cannot be written and they always read 0. */
+        RTC_RD = 0b1111111,
+/*      Valid RAM and Time (VRT)
+
+        This bit indicates the condition of the battery connected to the VBAT pin. This bit is not writeable and should always be 1 when read.
+        If a 0 is ever present, an exhausted internal lithium energy source is indicated and both the contents of the RTC data and RAM data are questionable.
+        This bit is unaffected by !RESET. */
+        RTC_VRT = 0b10000000
+};
+
+void rtc_tick();
+void time_update(char *nvrram, int reg);
+void time_get(char *nvrram);

src/win-config.c

@@ -11,6 +11,7 @@
 #include "fdd.h"
 #include "gameport.h"
 #include "model.h"
+#include "nvr.h"
 #include "resources.h"
 #include "sound.h"
 #include "video.h"
@@ -142,6 +143,9 @@ static BOOL CALLBACK config_dlgproc(HWND hdlg, UINT message, WPARAM wParam, LPAR
                 h=GetDlgItem(hdlg, IDC_CHECK4);
                 SendMessage(h, BM_SETCHECK, cga_comp, 0);
 
+                h=GetDlgItem(hdlg, IDC_CHECKSYNC);
+                SendMessage(h, BM_SETCHECK, enable_sync, 0);
+
                 h=GetDlgItem(hdlg, IDC_CHECKVOODOO);
                 SendMessage(h, BM_SETCHECK, voodoo_enabled, 0);
 
@@ -277,6 +281,9 @@ static BOOL CALLBACK config_dlgproc(HWND hdlg, UINT message, WPARAM wParam, LPAR
                         h = GetDlgItem(hdlg, IDC_CHECKSSI);
                         temp_SSI2001 = SendMessage(h, BM_GETCHECK, 0, 0);
 
+                        h = GetDlgItem(hdlg, IDC_CHECKSYNC);
+                        enable_sync = SendMessage(h, BM_GETCHECK, 0, 0);
+
                         h = GetDlgItem(hdlg, IDC_CHECKVOODOO);
                         temp_voodoo = SendMessage(h, BM_GETCHECK, 0, 0);
 
@@ -302,6 +309,7 @@ static BOOL CALLBACK config_dlgproc(HWND hdlg, UINT message, WPARAM wParam, LPAR
                         {
                                 if (MessageBox(NULL,"This will reset PCem!\nOkay to continue?","PCem",MB_OKCANCEL)==IDOK)
                                 {
+					savenvr();
                                         model = temp_model;
                                         romset = model_getromset();
                                         gfxcard = gfx;

src/win-time.c

@@ -1,43 +0,0 @@
-#include <windows.h>
-#include "ibm.h"
-#include "nvr.h"
-
-void time_get(char *nvrram)
-{
-	SYSTEMTIME systemtime;
-	int c, d;
-	uint8_t baknvr[10];
-
-        memcpy(baknvr,nvrram,10);
-        GetLocalTime(&systemtime);
-
-        d = systemtime.wSecond % 10;
-        c = systemtime.wSecond / 10;
-        nvrram[0] = d | (c << 4);
-        d = systemtime.wMinute % 10;
-        c = systemtime.wMinute / 10;
-        nvrram[2] = d | (c << 4);
-        d = systemtime.wHour % 10;
-        c = systemtime.wHour / 10;
-        nvrram[4] = d | (c << 4);
-        d = systemtime.wDayOfWeek % 10;
-        c = systemtime.wDayOfWeek / 10;
-        nvrram[6] = d | (c << 4);
-        d = systemtime.wDay % 10;
-        c = systemtime.wDay / 10;
-        nvrram[7] = d | (c << 4);
-        d = systemtime.wMonth % 10;
-        c = systemtime.wMonth / 10;
-        nvrram[8] = d | (c << 4);
-        d = systemtime.wYear % 10;
-        c = (systemtime.wYear / 10) % 10;
-        nvrram[9] = d | (c << 4);
-        if (baknvr[0] != nvrram[0] ||
-            baknvr[2] != nvrram[2] ||
-            baknvr[4] != nvrram[4] ||
-            baknvr[6] != nvrram[6] ||
-            baknvr[7] != nvrram[7] ||
-            baknvr[8] != nvrram[8] ||
-            baknvr[9] != nvrram[9])
-		nvrram[0xA]|=0x80;
-}

src/win.c

@@ -717,6 +717,7 @@ int WINAPI WinMain (HINSTANCE hThisInstance,
         TerminateThread(mainthreadh,0);
 //        pclog("Quited? %i\n",quited);
 //        pclog("Closepc\n");
+        savenvr();
         if (save_window_pos && window_remember)
                 saveconfig();
         closepc();
@@ -877,18 +878,21 @@ LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM
                         case IDM_FILE_RESET:
                         pause=1;
                         Sleep(100);
+                        savenvr();
                         resetpc();
                         pause=0;
                         break;
                         case IDM_FILE_HRESET:
                         pause=1;
                         Sleep(100);
+                        savenvr();
                         resetpchard();
                         pause=0;
                         break;
                         case IDM_FILE_RESET_CAD:
                         pause=1;
                         Sleep(100);
+                        savenvr();
                         resetpc_cad();
                         pause=0;
                         break;