********************************************************************
* s16550_large - 16550 serial driver
*
* $Id$
*
* Ed.    Comments                                       Who YY/MM/DD
* ------------------------------------------------------------------
* 28     Patched by Bob Brose to fix IRQ poll table     BOB ??/??/??
*        duplication bug

         nam   s16550
         ttl   os9 device driver    

* Disassembled 02/04/02 22:41:55 by Disasm v1.6 (C) 1988 by RML

         ifp1
         use   defsfile
         use   scfdefs
         endc

tylg     set   Drivr+Objct   
atrv     set   ReEnt+rev
rev      set   $01

         mod   eom,name,tylg,atrv,start,size

u0000    rmb   1
u0001    rmb   2
u0003    rmb   1
u0004    rmb   1
u0005    rmb   1
u0006    rmb   2
u0008    rmb   1
u0009    rmb   1
u000A    rmb   1
u000B    rmb   1
u000C    rmb   1
u000D    rmb   1
u000E    rmb   1
u000F    rmb   1
u0010    rmb   4
u0014    rmb   2
u0016    rmb   3
u0019    rmb   2
u001B    rmb   2
u001D    rmb   1
u001E    rmb   1
u001F    rmb   1
u0020    rmb   1
u0021    rmb   1
u0022    rmb   1
u0023    rmb   2
u0025    rmb   2
u0027    rmb   1
u0028    rmb   1
u0029    rmb   1
u002A    rmb   2
u002C    rmb   2
u002E    rmb   2
u0030    rmb   2
u0032    rmb   2
u0034    rmb   1
u0035    rmb   1
u0036    rmb   2
OutNxt   rmb   2
u003A    rmb   1
u003B    rmb   1
u003C    rmb   2
u003E    rmb   2
u0040    rmb   1
u0041    rmb   2
u0043    rmb   1
u0044    rmb   52
u0078    rmb   8
u0080    rmb   128
U0100    rmb   0
size     equ   .

         fcb   $03 

name     fcs   /s16550/
         fcb   28

L0015    fcb   $03 

start    lbra  Init
         lbra  Read
         lbra  Write
         lbra  GetStat
         lbra  SetStat
         lbra  Term

* Init
*
* Entry:
*    Y  = address of device descriptor
*    U  = address of device memory area
*
* Exit:
*    CC = carry set on error
*    B  = error code
*
Init     clrb  
         pshs  dp,b,cc
         lbsr  GetDP
         ldd   <u0001
         addd  #$0002
         pshs  y		save Y
         leax  >IRQPkt,pcr
         leay  >IRQRtn,pcr
         os9   F$IRQ    	install interrupt service routine
         puls  y		restore Y
         bcc   L004A		branch if ok
         puls  a,cc
         orcc  #Carry		set error flag
         puls  pc,dp		exit with error
L004A    lda   <M$Opt,y		get option count byte
         cmpa  #$1C		size of standard SCF?
         bls   L005F		branch if lower/same
         lda   <$2E,y		else grab driver specific byte
         anda  #$10
         sta   <u001F
         lda   <$2E,y
         anda  #$0F		mask out %00001111
         bne   L0061		if not zero, A holds number of 256 byte pages to allocate
L005F    lda   #$01		else allocate 1 256 byte page
L0061    clrb  
         pshs  u
         os9   F$SRqMem 	allocate memory
         tfr   u,x		transfer buffer start to X
         puls  u
         bcc   L0087
* Code here is in case of alloc error -- cleanup and return with error
         stb   $01,s
         ldx   #$0000
         ldd   <u0001
         addd  #$0002
         pshs  y
         leay  >IRQRtn,pcr
         os9   F$IRQ    
         puls  y
         puls  dp,b,cc
         orcc  #Carry
         rts   

* D = size of allocated buffer in bytes
L0087    stx   <u0032		store buffer start in several pointers
         stx   <u002C
         stx   <u002E
         std   <u0036
         leax  d,x		point at end of buffer
         stx   <u0030		store
         tfr   a,b		transfer size hi byte to B
         clra  			clear hi byte
         orb   #$02		OR original hi byte with 2
         andb  #$0E		clear bit 0 (b = %0000XXX0)
         lslb  
         lslb  
         lslb  
         lslb  
         tstb  
         bpl   L00A3
         ldb   #$80
L00A3    pshs  b,a
         ldd   <u0036
         subd  ,s++
         std   <u002A
         leax  <u0044,u
         stx   <u003E
         stx   <OutNxt
         stx   <u003A
         leax  >u0100,u
         stx   <u003C
         ldd   #$00BC
         std   <u0041
         clr   <u0034
         clr   <u0035
         clr   <u0040
         ldd   <$26,y
         std   <u001D
         lbsr  L0318
         ldx   <u0001
         lda   $05,x
         lda   ,x
         lda   $05,x
         lda   $06,x
         anda  #$B0
         sta   <u0020
         clrb  
         bita  #$10
         bne   L00E2
         orb   #$02
L00E2    bita  #$20
         bne   L00E8
         orb   #$01
L00E8    stb   <u0028
         orcc  #IntMasks
         lda   >L0015,pcr
         bmi   L00F5
         sta   >$FF7F
L00F5    lda   >$FF23
         anda  #$FC
         sta   >$FF23
         lda   >$FF22
         lda   >$0092
         ora   #$01
         sta   >$0092
         sta   >$FF92
         puls  pc,dp,b,cc

Write    clrb  
         pshs  dp,b,cc
         lbsr  GetDP
         ldx   <OutNxt		get address of next pos to save write char
         sta   ,x+		store char (A) at ,X and increment
         cmpx  <u003C		less than end of buffer?
         bcs   L011D
         ldx   <u003E
L011D    orcc  #IntMasks	mask interrupts
         cmpx  <u003A		reached end of buffer?
         bne   L0138		nope, still more room
         pshs  x
         lbsr  L05AD
         puls  x
         ldu   >D.Proc
         ldb   <P$Signal,u	get pending signal, if any
         beq   L0136		branch if none
         cmpb  #S$Intrpt	interrupt?
         bls   L013E		branch if lower or same
L0136    bra   L011D
L0138    stx   <OutNxt		update next output position
         inc   <u0040		increment output buffer size
         bsr   L0140
L013E    puls  pc,dp,b,cc
L0140    lda   #$0F
         bra   L0146
         lda   #$0D
L0146    ldx   <V.Port
         sta   $01,x
         rts   

Read     clrb  
         pshs  dp,b,cc
         lbsr  GetDP
         orcc  #IntMasks
         ldd   <u0034
         beq   L0169
         cmpd  #$0010
         lbne  L018F
         andcc #^IntMasks
         bsr   L01BD
L0163    orcc  #IntMasks
         ldd   <u0034
         bne   L018F
L0169    lbsr  L05AD
         ldx   >$0050
         ldb   <$19,x
         beq   L0178
         cmpb  #$03
         bls   L018A
L0178    ldb   $0C,x
         andb  #$02
         bne   L018A
         ldb   <u000E
         bne   L01A6
         ldb   <u0005
         beq   L0163
         orcc  #IntMasks
         bra   L0169
L018A    puls  dp,a,cc
         orcc  #Carry
         rts   
L018F    subd  #$0001
         std   <u0034
         ldx   <u002E
         lda   ,x+
         cmpx  <u0030
         bne   L019E
         ldx   <u0032
L019E    stx   <u002E
         andcc #^IntMasks
         ldb   <u000E
         beq   L01BB
L01A6    stb   <$3A,y
         clr   <u000E
         puls  dp,a,cc
         bitb  #$20
         beq   L01B6
         ldb   #$F4
         orcc  #Carry
         rts   
L01B6    ldb   #$DC
         orcc  #Carry
         rts   
L01BB    puls  pc,dp,b,cc
L01BD    pshs  cc
         ldx   <u0001
         ldb   <u0028
         bitb  #$70
         beq   L01D9
         bitb  #$20
         beq   L01DB
         orcc  #IntMasks
         ldb   <u0028
         andb  #$DF
         stb   <u0028
         lda   $04,x
         ora   #$02
         sta   $04,x
L01D9    puls  pc,cc
L01DB    bitb  #$10
         beq   L01EF
         orcc  #IntMasks
         ldb   <u0028
         andb  #$EF
         stb   <u0028
         lda   $04,x
         ora   #$01
         sta   $04,x
         bra   L01D9
L01EF    bitb  #$40
         beq   L01D9
         ldb   <u000F
         orcc  #IntMasks
         stb   <u0043
         lbsr  L0140
         ldb   <u0028
         andb  #$BF
         stb   <u0028
         bra   L01D9

GetStat  clrb  
         pshs  dp,b,cc
         lbsr  GetDP
         cmpa  #$01
         bne   L0226
         ldd   <u0034
         beq   L021E
         tsta  
         beq   L0217
         ldb   #$FF
L0217    ldx   $06,y
         stb   $02,x
         lbra  L0316
L021E    puls  b,cc
         orcc  #Carry
         ldb   #$F6
         puls  pc,dp
L0226    cmpa  #$28
         bne   L024E
         ldd   <u001D
         tst   <u001F
         beq   L0236
         bitb  #$04
         bne   L0236
         andb  #$F7
L0236    ldx   $06,y
         std   $08,x
         clrb  
         lda   <u0020
         bita  #$80
         bne   L0243
         orb   #$10
L0243    bita  #$20
         bne   L0249
         orb   #$40
L0249    stb   $02,x
         lbra  L0316
L024E    cmpa  #$06
         bne   L0256
         clrb  
         lbra  L0316
L0256    cmpa  #$C1
         bne   L026F
         ldx   $06,y
         ldd   #$00BC
         std   $06,x
         clra  
         ldb   <u0040
         std   $08,x
         ldb   <u0028
         andb  #$07
         stb   $02,x
         lbra  L0316
L026F    cmpa  #$D0
         bne   L02DD
         ldb   <u000E
         lbne  L01A6
         orcc  #IntMasks
         ldd   <u0030
         subd  <u002E
         cmpd  <u0034
         bcs   L0288
         ldd   <u0034
         beq   L021E
L0288    andcc #^IntMasks
         ldu   $06,y
         cmpd  u0008,u
         bls   L0293
         ldd   u0008,u
L0293    std   u0008,u
         beq   L02DB
         pshs  b,a
         pshs  u,y,x
         std   $02,s
         ldd   <u002E
         std   ,s
         ldd   u0006,u
         std   $04,s
         ldx   >$0050
         ldb   $06,x
         lda   >$00D0
         puls  u,y,x
         orcc  #IntMasks
         os9   F$Move   
         ldd   <u0034
         subd  ,s
         std   <u0034
         andcc #^IntMasks
         cmpd  #$0010
         bhi   L02CD
         addd  ,s
         cmpd  #$0010
         bls   L02CD
         lbsr  L01BD
L02CD    puls  b,a
         ldx   <u002E
         leax  d,x
         cmpx  <u0030
         bne   L02D9
         ldx   <u0032
L02D9    stx   <u002E
L02DB    bra   L0316
L02DD    cmpa  #$D2
         bne   L02F5
         ldd   #$0B04
         ldy   $06,y
         std   $01,y
         ldd   #$0077
         std   $06,y
         ldd   #$0001
         std   $08,y
         bra   L0316
L02F5    cmpa  #$26
         bne   L030E
         ldx   $06,y
         ldy   $03,y
         ldy   $04,y
         clra  
         ldb   <$2C,y
         std   $06,x
         ldb   <$2D,y
         std   $08,x
         bra   L0316
L030E    puls  b,cc
         orcc  #Carry
         ldb   #$D0
         puls  pc,dp
L0316    puls  pc,dp,b,cc
L0318    pshs  u
         tfr   b,a
         leau  >L07E3,pcr
         ldx   <u0001
         andb  #$0F
         lslb  
         lslb  
         leau  b,u
         lsra  
         lsra  
         lsra  
         lsra  
         lsra  
         eora  #$03
         anda  #$03
         pshs  a,cc
         lda   <u001D
         lsra  
         lsra  
         anda  #$38
         ora   $01,s
         sta   $01,s
         ora   #$80
         orcc  #IntMasks
         sta   $03,x
         ldd   ,u++
         exg   a,b
         std   ,x
         lda   $01,s
         sta   $03,x
         ldd   ,u
         sta   <u0021
         ora   #$06
         sta   $02,x
         stb   <u0029
         puls  pc,u,a,cc

SetStat  clrb  
         pshs  dp,b,cc
         lbsr  GetDP
         cmpa  #$D1
         lbne  L03F5
         ldu   $06,y
         ldx   u0006,u
         ldd   u0008,u
         pshs  x,b,a
         beq   L03D3
L036F    ldd   <u003A
         cmpd  <u003E
         bne   L037D
         ldd   <u003C
         subd  #$0001
         bra   L0387
L037D    subd  #$0001
         cmpd  <OutNxt
         bcc   L0387
         ldd   <u003C
L0387    subd  <OutNxt
         beq   L03D8
         cmpd  ,s
         bls   L0392
         ldd   ,s
L0392    pshs  b,a
         ldx   >$0050
         lda   $06,x
         ldb   >$00D0
         ldu   <OutNxt
         ldx   $04,s
         ldy   ,s
         orcc  #IntMasks
         os9   F$Move   
         ldd   ,s
         ldu   <OutNxt
         leau  d,u
         cmpu  <u003C
         bcs   L03B5
         ldu   <u003E
L03B5    stu   <OutNxt
         clra  
         ldb   <u0040
         addd  ,s
         stb   <u0040
         andcc #^IntMasks
         ldd   ,s
         ldx   $04,s
         leax  d,x
         stx   $04,s
         ldd   $02,s
         subd  ,s++
         std   ,s
         bne   L036F
         lbsr  L0140
L03D3    leas  $04,s
         lbra  L0543
L03D8    orcc  #IntMasks
         lbsr  L0140
         lbsr  L05AD
         ldx   >$0050
         ldb   <$19,x
         beq   L03EC
         cmpb  #$03
         bls   L03D3
L03EC    ldb   $0C,x
         andb  #$02
         bne   L03D3
         lbra  L036F
L03F5    cmpa  #$28
         bne   L0426
         ldy   $06,y
         ldd   $08,y
         tst   <u001F
         beq   L0408
         bitb  #$04
         bne   L0408
         orb   #$08
L0408    std   <u001D
         lbsr  L0318
         clr   <u0022
         tst   <u000C
         bne   L0423
         tst   <u000B
         bne   L0423
         tst   <u000D
         bne   L0423
         ldb   <u001D
         bitb  #$04
         bne   L0423
         inc   <u0022
L0423    lbra  L0543
L0426    cmpa  #$2B
         bne   L0441
         ldx   <u0001
         lda   $04,x
         pshs  x,a
         anda  #$FE
         sta   $04,x
         ldx   #$001E
         os9   F$Sleep  
         puls  x,a
         sta   $04,x
         lbra  L0543
L0441    cmpa  #$1D
         bne   L0491
         orcc  #IntMasks
         ldx   <u0001
         lda   <u0028
         ora   #$08
         sta   <u0028
         lda   #$0D
         sta   $01,x
         clr   <u0040
         ldd   <u003E
         std   <u003A
         std   <OutNxt
         lda   <u0021
         ora   #$04
         sta   $02,x
         clra  
         sta   ,x
L0464    lda   $05,x
         anda  #$40
         bne   L0476
         andcc #^IntMasks
         ldx   #$0001
         os9   F$Sleep  
         ldx   <u0001
         bra   L0464
L0476    lda   $03,x
         ora   #$40
         sta   $03,x
         ldx   #$001E
         os9   F$Sleep  
         ldx   <u0001
         anda  #$BF
         sta   $03,x
         lda   <u0028
         anda  #$F7
         sta   <u0028
         lbra  L0543
L0491    cmpa  #$C2
         bne   L04A7
         ldb   <u0028
         andb  #$F8
         stb   <u0028
         tst   <u0040
         lbeq  L0543
         lbsr  L0140
         lbra  L0543
L04A7    cmpa  #$1A
         bne   L04C4
         lda   $05,y
         ldy   $06,y
         ldb   $07,y
         orcc  #IntMasks
         ldx   <u0034
         bne   L04BD
         std   <u0025
         lbra  L0543
L04BD    puls  cc
         os9   F$Send   
         puls  pc,dp,b
L04C4    cmpa  #$1B
         bne   L04D5
         lda   $05,y
         cmpa  <u0025
         bne   L04D2
         clra  
         clrb  
         std   <u0025
L04D2    lbra  L0543
L04D5    cmpa  #$9A
         bne   L04E4
         lda   $05,y
         ldy   $06,y
         ldb   $07,y
         std   <u0023
         bra   L0543
L04E4    cmpa  #$9B
         bne   L04F6
         orcc  #IntMasks
         lda   $05,y
         cmpa  <u0023
         bne   L04F4
         clra  
         clrb  
         std   <u0023
L04F4    bra   L0543
L04F6    cmpa  #$2A
         lbne  L0511
         orcc  #IntMasks
         lda   $05,y
         ldx   #$0000
         cmpa  <u0025
         bne   L0509
         stx   <u0025
L0509    cmpa  <u0023
         bne   L050F
         stx   <u0023
L050F    bra   L0543
L0511    cmpa  #$C3
         bne   L052B
         orcc  #IntMasks
         ldb   #$0D
         stb   $01,x
         ldd   <u003E
         std   <OutNxt
         std   <u003A
         clr   <u0040
         ldb   <u0021
         orb   #$04
         stb   $02,x
         bra   L0543
L052B    cmpa  #$29
         bne   L053B
         ldx   <u0001
         lda   #$03
         sta   $04,x
         ldb   #$0F
         stb   $01,x
         bra   L0543
L053B    puls  b,cc
         orcc  #Carry
         ldb   #$D0
         puls  pc,dp
L0543    puls  pc,dp,b,cc

Term     clrb  
         pshs  dp,b,cc
         lbsr  GetDP
         orcc  #IntMasks
         clra  
         clrb  
         std   <u0034
         ldx   <u0032
         stx   <u002C
         stx   <u002E
         pshs  x,b,a
         ldb   $04,s
         tfr   b,cc
         ldx   >$0050
         lda   ,x
         sta   <u0004
         sta   <u0003
L0566    orcc  #IntMasks
         tst   <u0040
         bne   L0576
         ldx   <u0001
         ldb   $05,x
         eorb  #$20
         andb  #$20
         beq   L0585
L0576    orcc  #IntMasks
         lbsr  L05AD
         ldd   $02,s
         std   <u002C
         ldd   ,s
         std   <u0034
         bra   L0566
L0585    leas  $04,s
         clr   $01,x
         clr   $04,x
         andcc #^IntMasks
         ldd   <u0036
         pshs  u
         ldu   <u0032
         os9   F$SRtMem 
         puls  u
         ldx   #$0000
         ldd   <u0001
         addd  #$0002
         pshs  y
         leay  >IRQRtn,pcr
         os9   F$IRQ    
         puls  y
         puls  pc,dp,b,cc
L05AD    ldd   >$0050
         sta   <u0005
         tfr   d,x
         lda   $0C,x
         ora   #$08
         sta   $0C,x
         andcc #^IntMasks
         ldx   #$0001
         os9   F$Sleep  
         rts   

* Transfer hi-byte of U to Direct Page
GetDP    pshs  u
         puls  dp
         leas  $01,s
         rts   

L05CA    fdb   $0160,$0115,$001b,$01bb,$0004,$0004,$002a

* IRQ Service Routine
IRQRtn   fcb   $5f
L05D8    pshs  dp,b,cc
         bsr   GetDP
         clr   <u0027
         ldy   <u0001
         ldb   $02,y
         bitb  #$01
         beq   L05F4
         tfr   a,b
         andb  #$0E
         bne   L05F4
         puls  cc
         orcc  #Carry
         puls  pc,dp
L05F4    leax  >L05CA,pcr
         andb  #$0E
         abx   
         tfr   pc,d
         addd  ,x
         tfr   d,pc
L0601    ldb   $02,y
         bitb  #$01
         beq   L05F4
         lda   <u0005
         beq   L0616
         clrb  
         stb   <u0005
         tfr   d,x
         lda   $0C,x
         anda  #$F7
         sta   $0C,x
L0616    puls  pc,dp,b,cc
         ldx   <u002C
         lda   $05,y
         bmi   L062B
         ldb   <u0029
L0620    bsr   L0651
         decb  
         bne   L0620
         bra   L0629
         ldx   <u002C
L0629    lda   $05,y
L062B    bita  #$1E
         beq   L0634
         lbsr  L07BF
         bra   L0629
L0634    bita  #$01
         beq   L063C
L0638    bsr   L0651
         bra   L0629
L063C    tst   <u0027
         bne   L064D
         ldd   <u0025
         beq   L064D
         stb   <u0027
         os9   F$Send   
         clra  
         clrb  
         std   <u0025
L064D    stx   <u002C
         bra   L0601
L0651    lda   ,y
         beq   L0679
         tst   <u0022
         bne   L0679
         cmpa  <u000C
         bne   L0662
         lda   #$02
         lbra  L06FD
L0662    cmpa  <u000B
         bne   L066B
         lda   #$03
         lbra  L06FD
L066B    cmpa  <u000F
         beq   L06E3
         cmpa  <u0010
         beq   L06F2
         cmpa  <u000D
         lbeq  L070A
L0679    pshs  b
         sta   ,x+
         cmpx  <u0030
         bne   L0683
         ldx   <u0032
L0683    cmpx  <u002E
         bne   L0697
         ldb   #$02
         orb   <u000E
         stb   <u000E
         cmpx  <u0032
         bne   L0693
         ldx   <u0030
L0693    leax  -$01,x
         bra   L06A5
L0697    stx   <u002C
         ldd   <u0034
         addd  #$0001
         std   <u0034
         cmpd  <u002A
         beq   L06A7
L06A5    puls  pc,b
L06A7    ldb   <u0028
         bitb  #$70
         bne   L06A5
         lda   <u001D
         bita  #$02
         beq   L06BF
         orb   #$20
         stb   <u0028
         lda   $04,y
         anda  #$FD
         sta   $04,y
         bra   L06A5
L06BF    bita  #$01
         beq   L06CF
         orb   #$10
         stb   <u0028
         lda   $04,y
         anda  #$FE
         sta   $04,y
         bra   L06A5
L06CF    bita  #$08
         beq   L06A5
         orb   #$40
         stb   <u0028
         lda   <u0010
         beq   L06A5
         sta   <u0043
         ldb   #$0F
         stb   $01,y
         bra   L06A5
L06E3    lda   <u0028
         anda  #$FB
         sta   <u0028
         tst   <u0040
         beq   L06F1
         lda   #$0F
         sta   $01,y
L06F1    rts   
L06F2    lda   <u0028
         ora   #$04
         sta   <u0028
         lda   #$0D
         sta   $01,y
         rts   
L06FD    pshs  b
         tfr   a,b
         lda   <u0003
         stb   <u0027
         os9   F$Send   
         puls  pc,b
L070A    ldu   <u0009
         beq   L0711
         sta   <u0008,u
L0711    rts   
         ldx   <u003A
         lda   <u0043
         ble   L071E
         sta   ,y
         anda  #$80
         sta   <u0043
L071E    tst   <u0040
         beq   L0757
         ldb   <u0028
         bitb  #$08
         bne   L0757
         andb  #$07
         andb  <u001D
         bne   L0757
         ldb   <u003B
         negb  
         cmpb  #$0F
         bls   L0737
         ldb   #$0F
L0737    cmpb  <u0040
         bls   L073D
         ldb   <u0040
L073D    pshs  b
L073F    lda   ,x+
         sta   ,y
         decb  
         bne   L073F
         cmpx  <u003C
         bcs   L074C
         ldx   <u003E
L074C    stx   <u003A
         ldb   <u0040
         subb  ,s+
         stb   <u0040
L0754    lbra  L0601
L0757    lda   #$0D
         sta   $01,y
         bra   L0754
         lda   $06,y
         tfr   a,b
         andb  #$B0
         stb   <u0020
         ldb   <u0028
         andb  #$FC
         bita  #$10
         bne   L076F
         orb   #$02
L076F    bita  #$20
         bne   L0775
         orb   #$01
L0775    bita  #$08
         beq   L07AF
         bita  #$80
         bne   L0799
         lda   <u001D
         bita  #$10
         beq   L0791
         ldx   <u0016
         beq   L0791
         lda   #$01
L0789    sta   <$3F,x
         ldx   <$3D,x
         bne   L0789
L0791    lda   #$20
         ora   <u000E
         sta   <u000E
         andb  #$FB
L0799    tst   <u0027
         bne   L07AF
         stb   <u0028
         ldd   <u0023
         tstb  
         beq   L07B1
         os9   F$Send   
         stb   <u0027
         clra  
         clrb  
         std   <u0023
         bra   L07B1
L07AF    stb   <u0028
L07B1    lda   #$0F
         sta   $01,y
         lbra  L0601
         lda   $05,y
         bsr   L07BF
         lbra  L0601
L07BF    pshs  b
         clrb  
         bita  #$02
         beq   L07C8
         orb   #$04
L07C8    bita  #$04
         beq   L07CE
         orb   #$01
L07CE    bita  #$08
         beq   L07D4
         orb   #$02
L07D4    bita  #$10
         bne   L07DE
         orb   #$08
         orb   <u000E
         stb   <u000E
L07DE    puls  pc,b

* IRQ Flip/Mask/Priority Bytes
IRQPkt   fcb   $01,$01,$80

L07E3    fcb   $28
         fdb   $e901,$010f,$0001,$0107,$8041,$0403
         fdb   $c081,$0801,$e0c1,$0e00,$f0c1,$0e00,$78c1,$0e00
         fdb   $3c81,$0800,$1e81,$0800,$1481,$0800,$0f81,$0800
         fdb   $0a81,$0800,$0a81,$0800,$0a81,$0800,$0a81,$0800
         fdb   $2581
         fcb   $08

         emod
eom      equ   *
         end

