start of tape loading. hw works and have a generation script

monitor.c

@@ -1,5 +1,6 @@
 #include <stdint.h>
 #include "bios.h"
+#include "rom_layout.h"
 
 #define LINE_SIZE 80
 #define MAX_ARGS 40
@@ -97,8 +98,11 @@ static void print_help(void)
         " W addr byte... Write memory\r\n"
         " I port        Read I/O\r\n"
         " O port byte   Write I/O\r\n"
+        " K bank        Bank: 0=split, 1=upper 64K\r\n"
+        " R ON|OFF      Enable or disable ROM\r\n"
         " G addr        Execute\r\n"
         " B             Tiny BASIC\r\n"
+        " T             Tape loader\r\n"
         " H             Help\r\n");
 }
 
@@ -204,6 +208,35 @@ static void command_out(uint8_t argc, char **argv)
     bios_puts("OK\r\n");
 }
 
+static void command_bank(uint8_t argc, char **argv)
+{
+    uint16_t bank;
+
+    if (argc != 2 || !parse_hex(argv[1], &bank) || bank > 1) {
+        bios_puts("Usage: BANK 0|1\r\n");
+        return;
+    }
+    bios_bank((uint8_t)bank);
+    bios_puts("OK\r\n");
+}
+
+static void command_rom(uint8_t argc, char **argv)
+{
+    if (argc != 2) {
+        bios_puts("Usage: ROM ON|OFF\r\n");
+        return;
+    }
+    if (strings_equal(argv[1], "on")) {
+        bios_rom_enable();
+    } else if (strings_equal(argv[1], "off")) {
+        bios_rom_disable();
+    } else {
+        bios_puts("Usage: ROM ON|OFF\r\n");
+        return;
+    }
+    bios_puts("OK\r\n");
+}
+
 static void execute_address(uint16_t address)
 {
     bios_puts("Executing at ");
@@ -231,7 +264,16 @@ static void command_basic(uint8_t argc)
         bios_puts("Usage: B\r\n");
         return;
     }
-    execute_address(0x1000);
+    execute_address(TINYBASIC_ROM_ADDRESS);
+}
+
+static void command_tape(uint8_t argc)
+{
+    if (argc != 1) {
+        bios_puts("Usage: T\r\n");
+        return;
+    }
+    execute_address(TAPE_LOADER_ROM_ADDRESS);
 }
 
 static void execute_line(char *line)
@@ -253,10 +295,16 @@ static void execute_line(char *line)
         command_in(argc, argv);
     } else if (strings_equal(argv[0], "o") || strings_equal(argv[0], "out")) {
         command_out(argc, argv);
+    } else if (strings_equal(argv[0], "k") || strings_equal(argv[0], "bank")) {
+        command_bank(argc, argv);
+    } else if (strings_equal(argv[0], "r") || strings_equal(argv[0], "rom")) {
+        command_rom(argc, argv);
     } else if (strings_equal(argv[0], "g") || strings_equal(argv[0], "go")) {
         command_go(argc, argv);
     } else if (strings_equal(argv[0], "b") || strings_equal(argv[0], "basic")) {
         command_basic(argc);
+    } else if (strings_equal(argv[0], "t") || strings_equal(argv[0], "tape")) {
+        command_tape(argc);
     } else {
         bios_puts("Unknown command; type HELP\r\n");
     }