Get super simple kernel code running

sw/bios/boot2.s

@@ -11,7 +11,7 @@
 fatbuf                  = $A000
 filebuf                 = $B000
 
-.zeropage
+.bss
 
 tbase:  .res 2
 tlen:   .res 2
@@ -20,6 +20,11 @@ dlen:   .res 2
 olen:   .res 1
 otype:  .res 1
 
+filesiz: .res 1
+cluster: .res 2
+
+.zeropage
+
 userptr:        .res 2
 
 .segment "BOOTLOADER"
@@ -283,8 +288,6 @@ _start:
         ldy #$4
         jsr _cprintf
 
-        ;void* __fastcall__ memcpy (void* dest, const void* src, size_t count);
-
         lda tbase
         ldx tbase + 1
         jsr pushax
@@ -299,12 +302,39 @@ _start:
         ldx #>$1000
         jsr _SD_printBuf
 
+        lda userptr + 1
+        adc tlen + 1
+        tax
+        lda userptr
+        adc tlen
+        bcc @7
+        inx
+@7:     sta userptr
+        stx userptr + 1
+        lda #<word_str
+        ldx #>word_str
+        jsr pushax
+        lda userptr
+        ldx userptr + 1
+        jsr pushax
+        ldy #$4
+        jsr _cprintf
+
+        lda dbase
+        ldx dbase + 1
+        jsr pushax
+        lda userptr
+        ldx userptr + 1
+        jsr pushax
+        lda dlen
+        ldx dlen + 1
+        jsr _memcpy
+
+        jmp $1000
+
 @end:   bra @end
 
 
-filesiz: .res 1
-cluster: .res 2
-
 str: .asciiz "boot2\r\n"
 kernel_str: .asciiz "KERNEL  O65"
 _good: .asciiz "Found KERNEL\r\n"

sw/kernel/boot.s

@@ -5,7 +5,7 @@
 ; Startup code for cc65 (Single Board Computer version)
 
 .export   _init, _exit
-.import   _main
+.import   _main, _cputc
 
 .export   __STARTUP__ : absolute = 1        ; Mark as startup
 .import   __STACKSTART__, __STACKSIZE__       ; Linker generated
@@ -22,7 +22,12 @@
 ; ---------------------------------------------------------------------------
 ; A little light 6502 housekeeping
 
-_init:    LDX     #$FF                 ; Initialize stack pointer to $01FF
+_init:    
+            lda #'A'
+            jsr _cputc
+@1:         jmp @1
+
+          LDX     #$FF                 ; Initialize stack pointer to $01FF
           TXS
           CLD                          ; Clear decimal mode