X-Git-Url: http://wien.tomnetworks.com/gitweb/?a=blobdiff_plain;f=2_isa%2Fsrc%2Fbootrom.s;h=d38e1854527f517791893b82811e21e057a93780;hb=e342529c0374b6173bd50f346c088fc7e5eccfdc;hp=dc484d7fea490ffa0b0b5d321494cba2ea36319d;hpb=0221dfbdde27d9a2113565b7cd0d9109e65513ee;p=calu.git

diff --git a/2_isa/src/bootrom.s b/2_isa/src/bootrom.s
index dc484d7..d38e185 100644
--- 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
@@ -18,16 +22,14 @@ start:
 main:
 	ldi r10, UART_BASE@lo
 	ldih r10, UART_BASE@hi
+	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'
-	breq- bt_H
+	breq+ bt_H
 	br poll ; else
 
 ;-----
@@ -35,7 +37,7 @@ send_byte:
 	ldw r3, UART_STATUS(r10)
 	andx r3, UART_TRANS_EMPTY
 	brnz+ send_byte ; branch if not zero
-	stb r1, UART_TRANS(r10)
+	stw r1, UART_TRANS(r10)
 	ret
 
 ;-----
@@ -56,12 +58,11 @@ recv_byte:
 	andx r3, UART_RECV_NEW
 	brzs+ recv_byte; branch if zero
 	xor r0, r0, r0
-	ldb r0, UART_RECV(r10)
+	ldw r0, UART_RECV(r10)
 	ret
 
 ;-----
 recv_word:
-	xor r0, r0, r0
 	xor r1, r1, r1
 	call recv_byte
 	or r1, r0, r1
@@ -79,13 +80,14 @@ recv_word:
 	or r1, r0, r1
 
 	addi r0, r1, 0
-
 	ret
 
 ;-----
 bootrom:
-	br tehend
 	call recv_byte
+	ldi r1, 0x50 ; 'P'
+	call send_byte
+	br tehend
 
 	xor r1, r1, r1
 	cmpi r0, 0x57 ; 'W'
@@ -110,14 +112,14 @@ 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