Try command: keyprint

bare-bones-bootloader/bootloader.nasm

@@ -165,6 +165,16 @@ printCRLF:
     int 0x10
     ret
 
+printSpace:
+    mov ax, 0xE20
+    int 0x10
+    ret
+
+printALChar:
+    mov ah, 0xE
+    int 0x10
+    ret
+
 ; Routine for outputting string in 'si' register to screen
 print:
     mov ah, 0xE     ; Specify 'int 0x10' 'teletype output' function
@@ -284,20 +294,25 @@ wait_for_key_os:
         lea si, [.os_command_buffer]
         lea di, [.compare_with_dumpmem]
         call stringcompare
-        jne .no_str
+        jne .not_dumpmem
-        call printCRLF
         call printCRLF
         lea si, [start_sing_os]
         mov cx, 512
         call dumpmem
+    .not_dumpmem:
+        lea di, [.compare_with_keyprint]
+        call stringcompare
+        jne .no_str
+
         call printCRLF
-        call printCRLF
+        call keyprint
 
     .no_str:
         mov si, command_line
         call print_os
         jmp .return_enter
     .compare_with_dumpmem db 'dumpmem', 0
+    .compare_with_keyprint db 'keyprint', 0
 
     .end:
         mov si, exit_message
@@ -341,6 +356,26 @@ wait_for_key_os:
     .os_str_full db 13, 10, 'Buffer is full', 13, 10, 0
 
 
+keyprint:
+    pusha
+.keyprint_loop:
+    mov ax, 0x1000 ; BIOS call to wait for key
+    int 0x16
+    cmp ax, 0x11b ; ESC key
+    je .end_keyprint
+    
+    call dumpax
+    mov bx, ax
+    mov ax, 0xe20
+    int 0x10 ; print space
+    mov al, bl
+    int 0x10 ; print char
+    call printCRLF
+    jmp .keyprint_loop
+.end_keyprint:
+    popa
+    ret
+
 dumpax_os:
     pusha           ; save registers
     mov bx, ax