First working interactive shell for memory monitor

assembly/bios/drivers/arduino_terminal.asm

@@ -52,6 +52,6 @@ Term_readline:
     inc bc  ; point to next array position
     jp Term_readline
     term_readline_foundcr:   ; called when carriage return was found (end of line)
-    ld (bc), 0 ; Null-terminate string
+    ;ld (bc), 0 ; Null-terminate string
     ld bc, incoming_string  ; Returns read string pointer
     ret

assembly/bios/libs/strings.asm

@@ -0,0 +1,23 @@
+; Strings manipulation library
+; @author Daniele Verducci
+
+; Transforms case to upper
+
+Strings_strToUpper:
+    ; TODO
+    ret
+
+Strings_strToLower:
+    ; TODO
+    ret
+
+; Transforms character in A to uppercase. If is not a character, returns as is
+; @param A character to transform
+; @return A upper char
+Strings_charToUpper:
+    ; TODO
+    ret
+
+Strings_charToLower:
+    ; TODO
+    ret

assembly/bios/main.asm

@@ -37,17 +37,12 @@ IO_7: EQU 0xE0
 
 
 
-; CONSTANTS
-SYSINIT_GREETING:
-    DB "Pat80",10,0  ; null terminated string
 
 
 
-
+;include 'drivers/hd44780.asm'
-
+;include 'drivers/keyboard.asm'
-;include 'driver_hd44780.asm'
+include 'drivers/arduino_terminal.asm'
-;include 'driver_keyboard.asm'
-include 'driver_arduino_terminal.asm'
 include 'monitor.asm'
 
 ; SYSTEM CALLS
@@ -79,23 +74,6 @@ Readline:
 
 ; System initialization
 Sysinit:
-    ld bc, SYSINIT_GREETING
+    ; Start Monitor
-    call Print
+    call Monitor_main
-   
+    halt
-    _io_test_loop:
-        call Readline
-        call Print
-
-        ; call Printc
-        ; call Readline
-        ; ld a, (bc)
-        ; cp a, 0
-        ; jp z, _io_test_loop
-        ; ld (APP_VAR_SPACE), bc
-        ; ld bc, SAYS
-        ; call Print
-        ; ld bc, (APP_VAR_SPACE)
-        ; call Print
-    jp _io_test_loop
-
-

assembly/bios/monitor.asm

@@ -9,38 +9,54 @@
 ;   R (RUN) $pos Starts executing code from $pos
 ; The commands are entered with a single letter and the program completes the command
 
+include 'libs/strings.asm'
+
 ; CONSTANTS
 ; All monitor commands are 3 chars long.
-MON_WELCOME: DB "PAT80 MEmory MOnitor 0.1"
+MON_WELCOME: DB "PAT80 MEMORY MONITOR 0.1",10,0
 MON_COMMAND_HELP: DB "HELP",0  ; null terminated strings
-MON_COMMAND_DUMP: DB "DUMP",0  ; null terminated strings
+MON_COMMAND_DUMP: DB "DUMP",0
 MON_COMMAND_SET: DB "SET",0
 MON_COMMAND_LOAD: DB "LOAD",0
 MON_COMMAND_RUN: DB "RUN",0
 MON_ARG_HEX: DB "0x",0
-MON_HELP: DB "Available commands: HELP, DUMP, SET, LOAD, RUN"
+MON_HELP: DB 10,"Available commands: HELP, DUMP, SET, LOAD, RUN",0
+MON_ERR_SYNTAX: DB "    Syntax error",0
 
 Monitor_main:
     ; Print welcome string
     ld bc, MON_WELCOME
     call Print
     monitor_main_loop:
+        ; Newline
+        ld a, 10
+        call Printc
         ; Draw prompt char
         ld a, 62 ; >
         call Printc
         ; Read char from command line
-        call Readc:     ; blocking: returns when a character was read and placed in A reg
+        call Readc     ; blocking: returns when a character was read and placed in A reg
+        call Strings_charToUpper    ; user may enter lowercase char: transform to upper
+        call Printc     ; Print back the character to provide user feedback
         ; Switch case
-        cp (MON_COMMAND_HELP)  ; check incoming char is equal to command's first char
+        ld hl, MON_COMMAND_HELP
+        cp (hl)  ; check incoming char is equal to command's first char
         jp z, monitor_help
-        cp (MON_COMMAND_DUMP)
+        ld hl, MON_COMMAND_DUMP
+        cp (hl)
         jp z, monitor_dump
-        cp (MON_COMMAND_SET)
+        ld hl, MON_COMMAND_SET
+        cp (hl)
         jp z, monitor_set
-        cp (MON_COMMAND_LOAD)
+        ld hl, MON_COMMAND_LOAD
+        cp (hl)
         jp z, monitor_load
-        cp (MON_COMMAND_RUN)
+        ld hl, MON_COMMAND_RUN
+        cp (hl)
         jp z, monitor_run
+        ; Unrecognized command: print error
+        ld bc, MON_ERR_SYNTAX
+        call Print
     jp monitor_main_loop
 
 monitor_help:
@@ -49,28 +65,28 @@ monitor_help:
 
     ld bc, MON_HELP
     call Print
-    ret
+    jp monitor_main_loop
 
 monitor_dump:
     ld bc, MON_COMMAND_DUMP + 1 ; autocomplete command
     call Print
-    ret
+    jp monitor_main_loop
 
 monitor_set:
     ld bc, MON_COMMAND_SET + 1 ; autocomplete command
     call Print
-    ret
+    jp monitor_main_loop
 
 monitor_load:
     ld bc, MON_COMMAND_LOAD + 1 ; autocomplete command
     call Print
-    ret
+    jp monitor_main_loop
 
 monitor_run:
     ld bc, MON_COMMAND_RUN + 1 ; autocomplete command
     call Print
     jp APP_VAR_SPACE    ; Start executing code
-    ret
+    jp monitor_main_loop