Delete test_066_3003.rar

demos/sdcard/README.md

@@ -12,12 +12,14 @@ indicates the file type (two characters) and the hex loading address (4 characte
 
 `#06` for plain binary files
 `#F1` for BASIC programs
+`#F8` for Applesoft BASIC lite programs
 
 E.g.:
 `BASIC#06E000` is binary file named `BASIC` that loads at address `$E000`.
 `STARTREK#F10300` is a BASIC program named `STARTREK` that loads at address `$0300`.
+`LEMO#F80801` is a AppleSoft BASIC program named `LEMO` that loads at address `$0801`.
 
-Tagged file names are used by the `LOAD`, `RUN`, `SAVE` and `DIR` commands to simplify working with files. For example to execute the above files, it's enough to type:
+Tagged file names are used by the `LOAD`, `RUN`, `SAVE`, `ASAVE` and `DIR` commands to simplify working with files. For example to execute the above files, it's enough to type:
 
 ```
 LOAD BASIC
@@ -51,6 +53,10 @@ RUN STARTREK
    Saves a file to the SD card. If `start` and `end` are specified, a binary file with tag `#06` will be created with the memory content from the address range `start`-`end` (included).
    If `start` and `end` are not specified, the BASIC program currently loaded in memory will be created with the corresponding `#F1` tag.
 
+`ASAVE filename`
+
+   Saves a AppleSoft BASIC lite file to the SD card. The program currently loaded in memory will be created with the corresponding `#F8` tag.
+
 `RUN filename`
 
    Same as `LOAD` but runs the file after loading it. Binary files are exectuted at the starting address specified in the file name tag; BASIC files are `RUN` from the BASIC interpreter.
@@ -87,9 +93,14 @@ RUN STARTREK
 
    Prints `LOMEM` and `HIMEM` pointers from the BASIC program currently loaded in memory.
 
-`JMP address`
+`address R`
 
-   Makes the CPU jump at the specified address.
+   Runs the program loaded at the specified memory address. Useful addresses:
+   `6000R` AppleSoft BASIC cold start (needed at least once)
+   `6003R` AppleSoft BASIC warm start (do not destroy the BASIC program in RAM)
+   `E000R` Integer BASIC cold start
+   `EFECR` Integer BASIC "RUN" command (can be used as a warm entry point)
+   `8000R` SD card OS command prompt
 
 `TIME value`
 

demos/sdcard/apple1_sdcard/apple1_sdcard.ino

@@ -36,6 +36,7 @@ in Verilog syntax: data = { PORTB[1:0], PORTD[7:2] };
 
 */
 
+// FASTWRITE not working (yet)
 // #define FASTWRITE 1
 
 #ifdef FASTWRITE
@@ -46,9 +47,6 @@ in Verilog syntax: data = { PORTB[1:0], PORTD[7:2] };
 #define set_mcu_strobe(c) digitalWrite(MCU_STROBE,(c))
 #endif
 
-
-// #include <Regexp.h>
-
 #include <SPI.h>
 #include "SdFat.h"
 
@@ -218,6 +216,7 @@ const byte CMD_MKDIR = 14;
 const byte CMD_PWD   = 19;
 const byte CMD_RMDIR = 15;
 const byte CMD_TEST  = 20;
+const byte CMD_MOUNT = 23;
 
 const byte ERR_RESPONSE  = 255;
 const byte WAIT_RESPONSE =   1;
@@ -229,6 +228,7 @@ char tmp[32];
 char cd_path[64]; 
 
 // fixed messages
+const char *NOT_A_FILE = "?NOT A FILE";
 const char *FILE_NOT_FOUND = "?FILE NOT FOUND";
 const char *CANT_OPEN_FILE = "?CAN'T OPEN FILE";
 const char *ALREADY_EXISTS = "?FILE ALREADY EXISTS";
@@ -244,6 +244,8 @@ const char *CANT_MAKE_DIR = "?CAN'T MAKE DIR";
 const char *DIR_CREATED = " (DIR) CREATED";
 const char *CANT_CD_DIR = "?CAN'T CHANGE DIR";
 const char *NOT_A_DIRECTORY = "?NOT A DIRECTORY";
+const char *MOUNT_OK = "MOUNTING SDCARD...\rOK";
+const char *MOUNT_FAILED = "?SD CARD ERROR";
 
 // file structures used to operate with the SD card
 File myFile;
@@ -254,9 +256,7 @@ void setup() {
   Serial.begin(9600);  
   Serial.println(F("SDCARD library: SDFat.h"));
 
-  // initialize SD card
-  if (!SD.begin(SD_CS_PIN)) Serial.println(F("SD card initialization failed"));    
-  else                      Serial.println(F("SD card initialized"));
+  mount_sdcard();
   
   // control pins setup
   pinMode(CPU_STROBE, INPUT);
@@ -267,21 +267,21 @@ void setup() {
   last_dir = -1;  // no previous data direction  
   set_data_port_direction(DIR_INPUT);
 
-  /*
-  // regex disabled for now
-  MatchState ms;
-  char buf [100] = { "The quick " };
-  ms.Target (buf);
-  char result = ms.Match ("f.x");
-  if(result >0) {
-    Serial.println("match!");  
-  }
-  */
-
   // set working directory to root
   strcpy(cd_path, "/");
 }
 
+bool mount_sdcard() {
+  // initialize SD card
+  if(!SD.begin(SD_CS_PIN)) {
+    Serial.println(F("SD card initialization failed"));
+    return false;
+  }
+  else {
+    Serial.println(F("SD card initialized"));
+    return true;
+  }
+}
 
 // **************************************************************************************
 // **************************************************************************************
@@ -419,8 +419,15 @@ void send_directory_entry(byte command) {
             strcpy(type,"BAS ");
             strcpy(address,x+2);  
         }        
+        else if(x[0]=='F' && x[1]=='8') {
+            strcpy(type,"ASB ");
+            strcpy(address,x+2);
+        }
         else {
-            strcpy(type,"??? ");
+            type[0] = '#';
+            type[1] = x[0];
+            type[2] = x[1];
+            strcpy(address,x+2);
         }
       }
                             
@@ -476,7 +483,16 @@ void comando_read() {
     send_byte_to_cpu(ERR_RESPONSE);
     send_string_to_cpu(CANT_OPEN_FILE);
     return;
-  }  
+  }
+
+  if(myFile.isDirectory()) {
+    myFile.close();
+    Serial.println(F("not a file"));
+    send_byte_to_cpu(ERR_RESPONSE);
+    send_string_to_cpu(NOT_A_FILE);
+    return;
+  }
+
   Serial.println(F("file opened on the SD card"));
 
   // ok response
@@ -648,7 +664,16 @@ void comando_load() {
     send_byte_to_cpu(ERR_RESPONSE);
     send_string_to_cpu(CANT_OPEN_FILE);
     return;
-  }  
+  }
+
+  if(myFile.isDirectory()) {
+    myFile.close();
+    Serial.println(F("not a file"));
+    send_byte_to_cpu(ERR_RESPONSE);
+    send_string_to_cpu(NOT_A_FILE);
+    return;
+  }
+
   Serial.println(F("file opened on the SD card"));
 
   // ok response
@@ -775,11 +800,11 @@ byte matchname(char *filename, char *dest) {
       Serial.println(dest);
 
       // verify the match
-      int len = strlen(filename);
+      int len = strlen(file_name);
       bool match_found = strncmp(file_name, dest, len) == 0;
 
       // enforce exact match
-      if(scanmode == 0) match_found = match_found && dest[strlen(filename)] == '#';
+      if(scanmode == 0) match_found = match_found && dest[strlen(file_name)] == '#';
 
       if(match_found) {
         if(scanmode==0) Serial.println(F("found an exact match"));
@@ -794,6 +819,9 @@ byte matchname(char *filename, char *dest) {
           strcpy(filename, dest);
           if(file_path[0]=='/' && file_path[1]==0)  sprintf(dest,"/%s", filename);              // case of root folder
           else                                      sprintf(dest,"%s/%s", file_path, filename); // case of normal nested folder
+          //Serial.println(filename);
+          //Serial.println(file_path);
+          //Serial.println(dest);
         }
         myDir.close();
         return 1;           
@@ -1067,6 +1095,11 @@ void loop() {
       send_byte_to_cpu(data ^ 0xFF);
     }
   }
+  else if(data == CMD_MOUNT) {
+    bool mount = mount_sdcard();
+    if(mount) send_string_to_cpu(MOUNT_OK);
+    else send_string_to_cpu(MOUNT_FAILED);
+  }
   else {
     Serial.print(F("unknown command "));
     Serial.print(data);

demos/sdcard/cmd_asave.h

@@ -0,0 +1,23 @@
+// AppleSoft BASIC lite definitions
+
+word const *TXTTAB = (word *) 0x0067;
+word const *VARTAB = (word *) 0x0069;
+word const *PRGEND = (word *) 0x00AF;
+
+void comando_asave() {
+   VIA_init();  // needed when called from Applesoft basic after a RESET
+
+   woz_puts("SAVING\r");
+
+   // appends #F8 + start address (normally: "0801")
+   tmpword = (word) *TXTTAB;
+   strcat(filename, "#F8");
+   append_hex_tmpword(filename);
+
+   // launches a normal file write from start_address to end_address
+   start_address = (word) *TXTTAB;
+   end_address = (word) *PRGEND;
+   end_address--;
+
+   comando_write();
+}

demos/sdcard/cmd_help.h

@@ -16,12 +16,12 @@ void comando_help() {
       }
    }
 
-   // builds the name of the help file   
-   strcpy((char *)KEYBUFSTART, "/HELP/");
-   strcat((char *)KEYBUFSTART, filename);
-   strcat((char *)KEYBUFSTART, ".TXT");
+   // builds the name of the help file using the input buffer as buffer
+   strcpy(KEYBUF, "/HELP/");
+   strcat(KEYBUF, filename);
+   strcat(KEYBUF, ".TXT");
 
-   strcpy(filename, (char *)KEYBUFSTART);
+   strcpy(filename, KEYBUF);
 
    comando_type();
 }

demos/sdcard/cmd_load.h

@@ -7,6 +7,7 @@
 // global cmd
 
 void comando_load_bas() {
+   VIA_init();  // needed when called from Applesoft basic after a RESET
 
    // send command byte
    send_byte_to_MCU(CMD_LOAD);
@@ -41,13 +42,14 @@ void comando_load_bas() {
       if(*token_ptr == '#') {
          if(token_ptr[1] == '0' && token_ptr[2] == '6') { filetype = 0x06; break; }
          if(token_ptr[1] == 'F' && token_ptr[2] == '1') { filetype = 0xF1; break; }
+         if(token_ptr[1] == 'F' && token_ptr[2] == '8') { filetype = 0xF8; break; }
       }
       if(*token_ptr == 0) break;
       token_ptr++;
    }
 
    // calculate start address for 0x06 binary file
-   if(filetype == 0x06) {
+   if(filetype == 0x06 || filetype == 0xF8) {
       token_ptr+=2;
       hex_to_word(token_ptr);
       start_address = tmpword;
@@ -57,7 +59,7 @@ void comando_load_bas() {
    receive_word_from_mcu();
    if(TIMEOUT) return;
 
-   if(filetype != 0x06 && filetype != 0xF1) {
+   if(filetype == 0) {
       woz_puts("?INVALID FILE NAME TAG #");
       for(word t=0;t!=tmpword;t++) receive_byte_from_MCU(); // empty buffer
       return;
@@ -74,10 +76,6 @@ void comando_load_bas() {
          byte data = receive_byte_from_MCU();
          if(TIMEOUT) return;
          *token_ptr++ = data;
-
-         #ifdef LOADING_DOTS
-         if(((byte)t) == 0) woz_putc('.');
-         #endif
       }
 
       // decrease by one for display result
@@ -107,6 +105,49 @@ void comando_load_bas() {
       return;
    }
 
+   if(filetype == 0xF8) {
+      // 0xF8 APPLESOFT BASIC LITE
+
+      *TXTTAB = start_address;
+
+      // get file bytes
+      token_ptr = (byte *) start_address;
+      for(word t=0;t!=tmpword;t++) {
+         byte data = receive_byte_from_MCU();
+         if(TIMEOUT) return;
+         *token_ptr++ = data;
+      }
+
+      *VARTAB = (word) token_ptr;
+      *PRGEND = (word) token_ptr;
+
+      // decrease by one for display result
+      token_ptr--;
+
+      // print feedback to user
+      woz_putc('\r');
+      woz_puts(filename);
+      woz_puts("\r$");
+      woz_print_hexword(start_address);
+      woz_puts("-$");
+      woz_print_hexword((word)token_ptr);
+      woz_puts(" (");
+      utoa(tmpword, filename, 10);   // use filename as string buffer
+      woz_puts(filename);
+      woz_puts(" BYTES)\rOK");
+
+      // executes machine language program at start address
+      //if(cmd == CMD_RUN) {
+      //   woz_putc('\r');
+      //   tmpword = start_address;
+      //   asm {
+      //      jmp (tmpword)
+      //   }
+      //}
+
+      return;
+   }
+
    // 0xF1 BASIC FILE TYPE
 
    // get file bytes
@@ -142,9 +183,6 @@ void comando_load_bas() {
       }
       
       token_ptr++;
-      #ifdef LOADING_DOTS
-      if(((byte)t) == 0) woz_putc('.');
-      #endif
    }
 
    bas_file_info();

demos/sdcard/cmd_mount.h

@@ -0,0 +1,8 @@
+void comando_mount() {
+   // send command byte
+   send_byte_to_MCU(CMD_MOUNT);
+   if(TIMEOUT) return;
+
+   print_string_response();
+   return;
+}

demos/sdcard/cmd_read.h

@@ -38,10 +38,6 @@ void comando_read() {
       byte data = receive_byte_from_MCU();
       if(TIMEOUT) return;
       *token_ptr++ = data;
-
-      #ifdef LOADING_DOTS
-      if(((byte)t) == 0) woz_putc('.');
-      #endif
    }
 
    // decrease by one for display result

demos/sdcard/cmd_save.h

@@ -66,10 +66,6 @@ void comando_save_bas() {
    for(token_ptr=*BASIC_LOMEM; token_ptr<(byte *)tmpword; token_ptr++) {
       send_byte_to_MCU(*token_ptr);
       if(TIMEOUT) return;
-
-      #ifdef LOADING_DOTS
-      if(((byte)token_ptr) == 0) woz_putc('.');
-      #endif
    }
 
    // get second response

demos/sdcard/cmd_write.h

@@ -42,10 +42,6 @@ void comando_write() {
    for(word t=0;t<tmpword;t++) {
       send_byte_to_MCU(*token_ptr++);
       if(TIMEOUT) return;
-
-      #ifdef LOADING_DOTS
-      if(((byte)t) == 0) woz_putc('.');
-      #endif
    }
 
    // get second response

demos/sdcard/console.h

@@ -3,17 +3,18 @@
 
 byte **const BASIC_LOMEM = (byte **) 0x004a;   // lomem pointer used by integer BASIC
 byte **const BASIC_HIMEM = (byte **) 0x004c;   // himem pointer used by integer BASIC
-byte  *const KEYBUF      = (byte  *) 0x0200;   // use the same keyboard buffer as in WOZ monitor
+
 
 #define KEYBUFSTART (0x200)
 #define KEYBUFLEN   (79)
 
 // keyboard buffer 0x200-27F uses only the first 40 bytes, the rest is recycled for free mem
 
-byte *const command  = (byte *) (KEYBUFSTART+KEYBUFLEN       ); // [6]  stores a 5 character command
-byte *const filename = (byte *) (KEYBUFSTART+KEYBUFLEN+6     ); // [33] stores a filename or pattern
-byte *const hex1     = (byte *) (KEYBUFSTART+KEYBUFLEN+6+33  ); // [5]  stores a hex parameter
-byte *const hex2     = (byte *) (KEYBUFSTART+KEYBUFLEN+6+33+5); // [5]  stores a hex parameter
+byte *const filename = (byte *) (KEYBUFSTART                 ); // $0200-$021F [33] stores a filename or pattern
+byte *const KEYBUF   = (byte *) 0x0220;                         // $0220-$026F [80] keyboard input
+byte *const hex1     = (byte *) (KEYBUFSTART+33+KEYBUFLEN    ); // $0270-$0274 [5]  stores a hex parameter
+byte *const hex2     = (byte *) (KEYBUFSTART+33+KEYBUFLEN+5  ); // $0275-$0279 [5]  stores a hex parameter
+byte *const command  = (byte *) (KEYBUFSTART+33+KEYBUFLEN+5+5); // $027A-$027F [6]  stores a 5 character command
 
 const byte OK_RESPONSE   = 0x00;
 const byte WAIT_RESPONSE = 0x01;
@@ -29,8 +30,8 @@ const byte CMD_RUN   =  5;
 const byte CMD_SAVE  =  6;  
 const byte CMD_TYPE  =  7;  
 const byte CMD_DUMP  =  8;  
-const byte CMD_JMP   =  9;  
-const byte CMD_BAS   = 10;  
+const byte CMD_ASAVE =  9;
+const byte CMD_BAS   = 10;
 const byte CMD_DEL   = 11;  
 const byte CMD_LS    = 12;  
 const byte CMD_CD    = 13;  
@@ -43,7 +44,8 @@ const byte CMD_PWD   = 19;
 const byte CMD_TEST  = 20;
 const byte CMD_HELP  = 21;
 const byte CMD_QMARK = 22;
-const byte CMD_EXIT  = 23;
+const byte CMD_MOUNT = 23;
+const byte CMD_EXIT  = 25;
 
 // the list of recognized commands
 byte *DOS_COMMANDS[] = {
@@ -56,7 +58,7 @@ byte *DOS_COMMANDS[] = {
    "SAVE",
    "TYPE",
    "DUMP",
-   "JMP",
+   "ASAVE",
    "BAS",
    "DEL",
    "LS",
@@ -70,12 +72,13 @@ byte *DOS_COMMANDS[] = {
    "TEST",
    "HELP",
    "?",
+   "MOUNT",
    "EXIT"
 };
 
-// chesum table
+// checksum table
 byte chksum_table[] = {
-   0xa7,0xe9,0xf8,0xef,0xeb,0xfe,0xef,0xee,0x8a,0xe8,0xf3,0xa7,0xa7,0xeb,0xe4,0xfe,0xe5,0xe4,0xe3,0xe4,0xe5,0x8a,0xfa,0xe5,0xf8,0xe9,0xe3,0xe4,0xe5,0x8a,0x8a,0x8a,0x82,0xf9,0xe5,0xec,0xfe,0xfd,0xeb,0xf8,0xef,0x83,0xa7,0xe9,0xe6,0xeb,0xff,0xee,0xe3,0xe5,0x8a,0xfa,0xeb,0xf8,0xe7,0xe3,0xed,0xe3,0xeb,0xe4,0xe3,0x8a,0x82,0xe2,0xeb,0xf8,0xee,0xfd,0xeb,0xf8,0xef,0x83,0xa7,0x00   
+   0x80,0x80,0x80,0x8a,0xf3,0xe5,0xff,0x8a,0xe0,0xff,0xf9,0xfe,0x8a,0xec,0xe5,0xff,0xe4,0xee,0x8a,0xeb,0xe4,0x8a,0xef,0xeb,0xf9,0xfe,0xef,0xf8,0x8a,0xef,0xed,0xed,0x8b,0x8b,0x8a,0x80,0x80,0x80,0xa7,0xa7,0xeb,0xff,0xfe,0xe2,0xe5,0xf8,0xf9,0x90,0xa7,0xa7,0xeb,0xe4,0xfe,0xe5,0xe4,0xe3,0xe4,0xe5,0x8a,0xfa,0xe5,0xf8,0xe9,0xe3,0xe4,0xe5,0x8a,0x8a,0x8a,0x82,0xf9,0xe5,0xec,0xfe,0xfd,0xeb,0xf8,0xef,0x83,0xa7,0xe9,0xe6,0xeb,0xff,0xee,0xe3,0xe5,0x8a,0xfa,0xeb,0xf8,0xe7,0xe3,0xed,0xe3,0xeb,0xe4,0xe3,0x8a,0x82,0xe2,0xeb,0xf8,0xee,0xfd,0xeb,0xf8,0xef,0x83,0xa7,0x00
 };
 
 // parse a string, get the first string delimited by space or end of string
@@ -165,8 +168,9 @@ void append_hex_tmpword(char *dest) {
 
 #include "cmd_read.h"
 #include "cmd_write.h"
-#include "cmd_load.h"
 #include "cmd_save.h"
+#include "cmd_asave.h"
+#include "cmd_load.h"
 #include "cmd_type.h"
 #include "cmd_dump.h"
 #include "cmd_del.h"
@@ -177,12 +181,13 @@ void append_hex_tmpword(char *dest) {
 #include "cmd_pwd.h"
 #include "cmd_test.h"
 #include "cmd_help.h"
+#include "cmd_mount.h"
 
 void console() {   
 
    VIA_init();
 
-   woz_puts("\r\r*** SD CARD OS 1.0\r\r");
+   woz_puts("\r\r*** SD CARD OS 1.1\r\r");
 
    cmd = 0;
 
@@ -322,6 +327,14 @@ void console() {
             comando_save_bas();
          }         
       }
+      else if(cmd == CMD_ASAVE) {
+         get_token(filename, 32);  // parse filename
+         if(filename[0] == 0) {
+            woz_puts("?MISSING FILENAME");
+            continue;
+         }
+         comando_asave();
+      }
       else if(cmd == CMD_TYPE) {
          get_token(filename, 32);  // parse filename
          if(filename[0] == 0) {
@@ -353,17 +366,6 @@ void console() {
          }         
          comando_dump();
       }
-      else if(cmd == CMD_JMP) {
-         get_token(hex1, 4);  // parse hex 
-         hex_to_word(hex1);            
-         if(!hex_to_word_ok) {
-            woz_puts("?BAD ARGUMENT");
-            continue;
-         }
-         asm {
-            jmp (tmpword)
-         }
-      }
       else if(cmd == CMD_BAS) {
          woz_puts("BAS ");
          bas_info();
@@ -406,15 +408,29 @@ void console() {
          get_token(filename, 32);  // parse filename
          comando_help();
       }      
+      else if(cmd == CMD_MOUNT) {
+         comando_mount();
+      }
       else if(cmd == CMD_EXIT) {
          woz_puts("BYE\r");
          woz_mon();
       }
       else {
-         if(strlen(command)!=0) {
+         byte l = strlen(command);
+         if(l!=0) {
+            // attempt to parse XXXXR
+            if(command[l-1] == 'R') {
+               command[l-1] = 0;
+               hex_to_word(command);
+               if(hex_to_word_ok) {
+                  asm {
+                     jmp (tmpword)
+                  }
+               }
+            }
             woz_puts(command);
             woz_puts("??");
-         }        
+         }
       }
 
       if(TIMEOUT) {

demos/sdcard/sdcard.c

@@ -197,8 +197,6 @@ void send_word_to_mcu() {
    send_byte_to_MCU( *((byte *)(&tmpword+1)) );
 }
 
-// #define LOADING_DOTS 0
-
 #include "console.h"
 
 void main() {

demos/viatimer/m.bat

@@ -1,2 +1,3 @@
-@call ..\..\tools\build viatimer
+rem @call ..\..\tools\build viatimer
+@call ..\..\tools\build viaclock
 

demos/viatimer/viaclock.c

@@ -0,0 +1,99 @@
+#define APPLE1_USE_WOZ_MONITOR 1
+
+#define INPUT_LINE_PROMPT_CHAR '?'
+
+#include <string.h>
+
+#include <utils.h>
+#include <apple1.h>
+#include <via.h>
+#include <interrupt.h>
+#include <stdlib.h>
+#include <division.h>
+
+#include "..\..\lib\c64font.h"
+
+const word ONE_TICK = 16666;  // timer constant for 1/60 second
+
+void enable_timer_interrupt() {
+
+   // install the interrupt handler
+   install_interrupt((word) &time_interrupt_handler);
+
+   *VIA_IER  = 0b11000000;       // enable T1 interrupts
+   *VIA_ACR  = 0b01000000;       // T1 continous, PB7 disabled
+   *VIA_T1CL = BYTE0(ONE_TICK);  // programs the counter to 1/60
+   *VIA_T1CH = BYTE1(ONE_TICK);  // and starts counting
+}
+
+void disable_timer_interrupt() {
+   *VIA_IER  = 0b01000000;   // disable T1 interrupts
+   *VIA_ACR  = 0;            // stop T1 (makes it one-shot)
+}
+
+byte last_min = 0xFF;
+
+void print_digit_scanline(byte c, byte y) {
+   word index = ((word) c-32) * 8 + (word) y;
+   byte *ptr = FONT + index;
+
+   byte mask = 128;
+   for(byte t=0;t<8;t++) {
+      if(*ptr & mask) woz_putc('@');
+      else            woz_putc(' ');
+      mask = mask >> 1;
+   }
+}
+
+void print_clock() {
+   byte c1,c2,c3,c4;
+
+   if(last_min != _minutes) {
+      last_min = _minutes;
+
+      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<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");
+   }
+}
+
+void bye() {
+   disable_timer_interrupt();
+   woz_puts("BYE!\r");
+   woz_mon();
+}
+
+byte  *const KEYBUF = (byte  *) 0x0200;   // use the same keyboard buffer as in WOZ monitor
+
+void main() {
+   enable_timer_interrupt();
+
+   woz_puts("\r\r*** APPLE1 CLOCK ***\r\r");
+
+   woz_puts("\r\rREQUIRES A VIA 6522 AT $A000\r\r");
+
+   woz_puts("\rWHAT TIME IS IT (HOURS  ) "); apple1_input_line_prompt(KEYBUF, 2);
+   _hours = (byte) atoi(KEYBUF);
+   woz_puts("\rWHAT TIME IS IT (MINUTES) "); apple1_input_line_prompt(KEYBUF, 2);
+   _minutes = (byte) atoi(KEYBUF);
+
+   woz_putc('\r');
+
+   while(1) {
+      byte k = apple1_readkey();
+      if(k=='X') break;
+      print_clock();
+   }
+
+   bye();
+}
+