bootromfun: stuff zum debuggen fuern stefan :/

[calu.git] / 2_isa / src / bootrom.s

diff --git a/2_isa/src/bootrom.s b/2_isa/src/bootrom.s
index dc484d7fea490ffa0b0b5d321494cba2ea36319d..18bc1ca4dc54cfb2cbc2cbcd35611d31207e9bd7 100644 (file)
--- a/2_isa/src/bootrom.s
+++ b/2_isa/src/bootrom.s
@@ -9,6 +9,10 @@
        .define UART_TRANS_EMPTY, 0x1
        .define UART_RECV_NEW, 0x2
 
+       .define PBASE, 0x2030
+       .define PADDR, 0x4
+       .define PDATA, 0x8
+
 ;-----
 start:
        br+ main
@@ -18,17 +22,19 @@ start:
 main:
        ldi r10, UART_BASE@lo
        ldih r10, UART_BASE@hi
-poll:
-       ldw r3, UART_STATUS(r10)
-       andx r3, UART_RECV_NEW
-       brzs+ poll; branch if zero
+       ldi r11, PBASE@lo
+       ldih r11, PBASE@hi
+;poll:
+;      ldw r3, UART_STATUS(r10)
+;      andx r3, UART_RECV_NEW
+;      brzs+ poll; branch if zero
 
        call recv_byte
        ; we received the enter bootrom sign
-       xor r1, r1, r1
        cmpi r0, 0x48 ; 'H'
+       xor r1, r1, r1 ; TODO: wieder raufziehen
        breq- bt_H
-       br poll ; else
+       ; br poll ; else
 
 ;-----
 send_byte:
@@ -52,16 +58,15 @@ send_word:
 
 ;-----
 recv_byte:
-       ldw r3, UART_STATUS(r10)
-       andx r3, UART_RECV_NEW
-       brzs+ recv_byte; branch if zero
+;      ldw r3, UART_STATUS(r10)
+;      andx r3, UART_RECV_NEW
+;      brzs+ recv_byte; branch if zero
        xor r0, r0, r0
-       ldb r0, UART_RECV(r10)
+;      ldb r0, UART_RECV(r10)
        ret
 
 ;-----
 recv_word:
-       xor r0, r0, r0
        xor r1, r1, r1
        call recv_byte
        or r1, r0, r1
@@ -79,13 +84,12 @@ recv_word:
        or r1, r0, r1
 
        addi r0, r1, 0
-
        ret
 
 ;-----
 bootrom:
-       br tehend
        call recv_byte
+       br tehend
 
        xor r1, r1, r1
        cmpi r0, 0x57 ; 'W'
@@ -110,14 +114,14 @@ bootrom:
 bt_H:
        ldi r1, 0x4f ; 'O'
        call send_byte
-       ; br bootrom ; FIXME
-       br tehend
+       call send_byte
+       br bootrom
 
 bt_W:
        call recv_word ; receive addr
-       mov r6, r0
+       stw r0, PADDR(r11)
        call recv_word ; receive instr
-       stx r0, 0(r6)
+       stw r0, PDATA(r11)
        ldi r1, 0x44 ; 'D'
        call send_byte
        br bootrom