trs80load: Work on the M1 loader

With these changes we actually get to execute Fuzix code... not a lot of it
admittedly at this point!

diff --git a/Kernel/platform-trs80m1/trs80load.s b/Kernel/platform-trs80m1/trs80load.s
index c0ed0c5..2cae40d 100644 (file)
--- a/Kernel/platform-trs80m1/trs80load.s
+++ b/Kernel/platform-trs80m1/trs80load.s
@@ -48,21 +48,17 @@ lastsec:    ld a, #0                        ; self modifying to save space
            ld (lastsec+1), a           ; track number... (start on 1)
            cp #33
            jp z, booted
-           ld (FDCTRK),a
-           ld (0x3CF0),a               ; XX
-           ld (hl),#21                 ; seek, lowest step speed
-           ld b, c                     ; 0x00 256 delays
+           ld (de),a                   ; Desired track into data
+           ld (hl),#0x1B               ; seek, lowest step speed
+           push bc
+           ld b, #0                    ; 0x00 256 delays
 cmd1:      djnz cmd1
-cmdwait:    bit 0, (hl)
-           jr z, seekstat
-           bit 7, (hl)
-           jr z, cmdwait
 seekstat:
+           pop bc
+           bit 0, (hl)
+           jr nz, seekstat
            ld a,(hl)
            and #0x18
-           bit 0, a
-           jr nz, seekstat
-           or a
            jr z, secmove
            call printse
            .ascii 'seek\0'
@@ -71,7 +67,6 @@ secmove:    xor a
            dec a       
            ld (nextsec+1), a
 nextsec:
-           ld (0x3CF1),a       ; XX
            ld a, #255          ; self modifying sector count
            inc a
            ld (nextsec+1), a
@@ -93,8 +88,10 @@ floppy_read:
            ld (LATCHD0), a             ; keep motor on
            ld a, #0x8C                 ; READ
            ld (hl), a
+           push bc
            ld b, a                     ; 8C is an acceptable delay!
 l1:        djnz l1
+           pop bc
 flopin:            bit 1,(hl)
            jr z, flopin
            ld a,(de)
@@ -102,7 +99,7 @@ flopin:          bit 1,(hl)
            inc c                       ; page aligned
            jr nz,flopin
            inc b                       ; correct bc for next call
-           jr nc, flopstat             ; passed FFFF ?
+           jr nz, flopstat             ; passed FFFF ?
            ld b,#0x80                  ; go back to 8000 and change bank
            ld a,#1
             out (0x43),a
@@ -119,7 +116,7 @@ fail:           jr fail
 
 
 printse:
-          ld de, #0x3850
+          ld de, #0x3C40
 prints:
           pop hl
 printsl: