diff --git a/demos/viatimer/m.bat b/demos/viatimer/m.bat
index 1e70586..19dbe05 100644
--- a/demos/viatimer/m.bat
+++ b/demos/viatimer/m.bat
@@ -1,3 +1,8 @@
-rem @call ..\..\tools\build viatimer
+@call ..\..\tools\build viatimer
 @call ..\..\tools\build viaclock
 
+copy out\viatimer.bin ..\..\..\apple1-emu\software\sdcard_image\PLAB\VIATIMER#060280 /y
+copy out\viaclock.bin   ..\..\..\apple1-emu\software\sdcard_image\PLAB\VIACLOCK#060280 /y
+
+
+
diff --git a/demos/viatimer/viaclock.c b/demos/viatimer/viaclock.c
index 8902474..77d9a64 100644
--- a/demos/viatimer/viaclock.c
+++ b/demos/viatimer/viaclock.c
@@ -13,7 +13,9 @@
 
 #include "..\..\lib\c64font.h"
 
-const word ONE_TICK = 16666;  // timer constant for 1/60 second
+// const word ONE_TICK = 15996;  // timer constant for 1/60 second calculated as 14318180/14*61/65/60
+
+word ONE_TICK;
 
 void enable_timer_interrupt() {
 
@@ -32,6 +34,7 @@ void disable_timer_interrupt() {
 }
 
 byte last_min = 0xFF;
+byte last_sec = 0xFF;
 
 void print_digit_scanline(byte c, byte y) {
    word index = ((word) c-32) * 8 + (word) y;
@@ -54,15 +57,34 @@ void print_clock() {
       c1 = divr8u(_hours, 10, 0); c2 = rem8u;
       c3 = divr8u(_minutes, 10, 0); c4 = rem8u;
 
-      woz_puts("\r\r\r\r\r\r\r\r");
+      for(byte t=0;t<24;t++) woz_putc('\r');      
       for(byte t=0;t<8;t++) {
          print_digit_scanline(c1+'0',t);
          print_digit_scanline(c2+'0',t);
          print_digit_scanline(   ':',t);
          print_digit_scanline(c3+'0',t);
          print_digit_scanline(c4+'0',t);
-      }
-      woz_puts("\r\r\r\r\r\r\r\r");
+      }      
+      for(byte t=0;t<4;t++) woz_putc('\r');
+      last_sec = 0;
+   }   
+
+   if(last_sec < _seconds) {
+      //if(last_sec > 20) woz_putc('>');
+      /*
+           if(last_sec < 10) { woz_puts("...10 "); last_sec = 10; }
+      else if(last_sec < 20) { woz_puts("...20 "); last_sec = 20; }
+      else if(last_sec < 30) { woz_puts("...30 "); last_sec = 30; }
+      else if(last_sec < 40) { woz_puts("...40 "); last_sec = 40; }
+      else if(last_sec < 50) { woz_puts("...50 "); last_sec = 50; }
+      */
+
+      c1 = divr8u(last_sec, 10, 0); c2 = rem8u;
+      woz_putc(' ');
+      woz_putc(c1+'0');
+      woz_putc(c2+'0');
+      woz_putc(' ');
+      last_sec++;
    }
 }
 
@@ -72,19 +94,52 @@ void bye() {
    woz_mon();
 }
 
+void detect_machine_type() {
+
+   // detect if VIA 6522 is present
+   *VIA_DDRB = 0xA5;
+   if(*VIA_DDRB != 0xA5) {                    
+      woz_puts("\r\rSORRY, THIS PROGRAM NEEDS A VIA 6522 \rMAPPED AT ADDRESS $A000\r\r");
+      bye();
+   }
+
+   // detect if genuine apple1 or replica-1
+
+   woz_puts("\r\rRUNNING ON ");
+
+   const word *ptr1 = (word *) 0xF000;
+   const word *ptr2 = (word *) 0xFF00;
+
+   if(*ptr1 == *ptr2) {
+      // genuine Apple1
+      ONE_TICK = 15996;  // timer constant for 1/60 second calculated as 14318180/14*61/65/60      
+      woz_puts("GENUINE APPLE1");
+   }
+   else {
+      // Replica-1
+      ONE_TICK = 17045;  // timer constant for 1/60 second calculated as 14318180/14/60      
+      woz_puts("APPLE1 REPLICA-1");
+   }
+
+   woz_puts("\r\r");   
+}
+
 byte  *const KEYBUF = (byte  *) 0x0200;   // use the same keyboard buffer as in WOZ monitor
 
 void main() {
-   enable_timer_interrupt();
+   woz_puts("\r\r*** APPLE-1 CLOCK ***\r\r");
 
-   woz_puts("\r\r*** APPLE1 CLOCK ***\r\r");
+   detect_machine_type();
 
-   woz_puts("\r\rREQUIRES A VIA 6522 AT $A000\r\r");
+   woz_puts("\rWHAT TIME IS IT ?\r");
 
-   woz_puts("\rWHAT TIME IS IT (HOURS  ) "); apple1_input_line_prompt(KEYBUF, 2);
+   woz_puts("\r(HOURS  ) "); apple1_input_line_prompt(KEYBUF, 2);
    _hours = (byte) atoi(KEYBUF);
-   woz_puts("\rWHAT TIME IS IT (MINUTES) "); apple1_input_line_prompt(KEYBUF, 2);
+   woz_puts("\r(MINUTES) "); apple1_input_line_prompt(KEYBUF, 2);
    _minutes = (byte) atoi(KEYBUF);
+   _seconds = 0;
+
+   enable_timer_interrupt();
 
    woz_putc('\r');