====== MODBOOT ======
<code>
Header for : Boot
Module size: $189  #393
Module CRC : $B1FA65 (Good)
Hdr parity : $70
Edition    : $00  #0
Ty/La At/Rv: $C1 $81
System mod, 6809 Obj, re-ent, R/O

</code>
===== CODE =====
<code>
* Disassembly by Os9disasm of modboot

 mod L0189,L000d,$c1,$81,L0012,D0005

* OS-9 system function equates

F$SchBit equ $12
F$SRqMem equ $28

* class D external label equates

D0016 equ $0016
D0018 equ $0018
D0020 equ $0020
D0022 equ $0022
Dffff equ $ffff

* OS9 data area definitions

 rmb 5
D0005 equ .

L000d fcb $42
 clr   15,s
 andb  >$004f
L0012 equ *-1
 ldb   #5
L0015 pshs  a
 decb  
 bne   L0015
 tfr   s,u
 ldx   #-192
 leax  8,x
 lda   #$d0
 sta   ,x
 lbsr  L017f
 lda   ,x
 lda   #255
 sta   4,u
 leax  L0117,pcr
 stx   $010a
 lda   #$7e
 sta   $0109
 lda   #8
 sta   -192
 ldd   #$c350
L0042 nop   
 nop   
 subd  #1
 bne   L0042
 pshs  d,x,u
 clra  
 clrb  
 ldy   #1
 ldx   D0020
 ldu   D0022
 os9 F$SchBit
 bcs   L009b
 exg   a,b
 ldu   4,s
 std   2,u
 clrb  
 ldx   #0
 bsr   L00b9
 bcs   L009b
 ldd   D0018,y
 std   ,s
 os9 F$SRqMem
 bcs   L009b
 stu   2,s
 ldu   4,s
 ldx   2,s
 stx   2,u
 ldx   D0016,y
 ldd   D0018,y
 beq   L0094
L0082 pshs  d,x
 clrb  
 bsr   L00b9
 bcs   L0099
 puls  d,x
 inc   2,u
 leax  1,x
 subd  #$0100
 bhi   L0082
L0094 clrb  
 puls  d
 bra   L009d
L0099 leas  4,s
L009b leas  2,s
L009d puls  x,u
 leas  5,s
 rts   
L00a2 clr   ,u
 clr   4,u
 lda   #5
L00a8 ldb   #$43
 pshs  a
 lbsr  L016a
 puls  a
 deca  
 bne   L00a8
 ldb   #3
 lbra  L016a
L00b9 lda   #$91
 cmpx  #0
 bne   L00d1
 bsr   L00d1
 bcs   L00c8
 ldy   2,u
 clrb  
L00c8 rts   
L00c9 bcc   L00d1
 pshs  d,x
 bsr   L00a2
 puls  d,x
L00d1 pshs  d,x
 bsr   L00dc
 puls  d,x
 bcc   L00c8
 lsra  
 bne   L00c9
L00dc bsr   L0128
 bcs   L00c8
 ldx   2,u
 orcc  #$50
 pshs  y
 ldy   #-1
 ldb   #$80
 stb   -184
 ldb   #$39
 stb   -192
 lbsr  L017f
 ldb   #$b9
 lda   #2
L00fb bita  -184
 bne   L010d
 leay  Dffff,y
 bne   L00fb
 lda   #9
 sta   -192
 puls  y
 bra   L0124
L010d lda   -181
 sta   ,x+
 stb   -192
 bra   L010d
L0117 leas  12,s
 puls  y
 ldb   -184
 bitb  #4
 lbeq  L0164
L0124 comb  
 ldb   #$f4
 rts   
L0128 clr   ,u
 tfr   x,d
 cmpd  #0
 beq   L0141
 clr   ,-s
 bra   L0138
L0136 inc   ,s
L0138 subd  #$0012
 bcc   L0136
 addb  #$12
 puls  a
L0141 incb  
 stb   -182
 ldb   4,u
 stb   -183
 cmpa  4,u
 beq   L0162
 sta   4,u
 sta   -181
 ldb   #$13
 bsr   L016a
 pshs  x
 ldx   #$222e
L015c leax  -1,x
 bne   L015c
 puls  x
L0162 clrb  
 rts   
L0164 bitb  #$98
 bne   L0124
 clrb  
 rts   
L016a bsr   L017d
L016c ldb   -184
 bitb  #1
 bne   L016c
 rts   
L0174 lda   #9
 sta   -192
 stb   -184
 rts   
L017d bsr   L0174
L017f lbsr  L0182
L0182 lbsr  L0185
L0185 rts   

 emod 

L0189 equ *

 end
</code>
===== RTS =====
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