gno/lib/lsaneglue/findfpcp.asm

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mcopy findfpcp.mac
*
* Find the slot the FPE or NumberCruncher card is in
*
* Returns the slot number or -1 if FPCP card cannot be found.
*
* For slots 1-5 and 7, findfpcp() can find the card
* regardless of the Slot setting in the Control Panel.
* For slot 6, the Control Panel must be set to "Your Card"
* for the function to be able to find the card.
*
* Written in 1997 by Soenke Behrens, from Merlin code by
* Albert Chin-A-Young
* This code is hereby place into the Public Domain
*
*
* Dummy function to take care of findfpcp.root, which
* can then be discarded.
*
dummy start
end
****************************************************************
*
* int findfpcp (void);
*
* Find slot FPCP card is in
*
* See also: Floating-Point Coprocessor Manual by Albert
* Chin-A-Young
*
****************************************************************
*
findfpcp start
SETINTC3ROM equ $e1c00a ; enable internal slot 3 ROM
SETSLOTC3ROM equ $e1c00b ; enable external slot 3 ROM
RDC3ROM equ $e1c017 ; bit 7 = 1 if slot c3 space enabled
SLTROMSEL equ $e1c02d ; slot ROM select
csub
sei Disable interrupts
short m 8-bit accumulator
lda #0 enable slot 3 ROM as FPCP
sta SETSLOTC3ROM might be in slot 3
lab1 lda RDC3ROM wait for external slot 3
bpl lab1 space to be enabled
lda SLTROMSEL store previous value in Y
tay
ora #%10110110 enable slot 1, 2, 4, 5, 7 ROM
sta SLTROMSEL
long m 16-bit accumulator
ldx #$c100 Start with slot 1
search lda $e00004,x read slot at address $04,
cmp id_bytes $06 and $0b. If no match
bne next_slot is found, exit, else set up
lda $e00006,x base address
cmp id_bytes+2
bne next_slot
lda $e0000b,x
cmp id_bytes+4
beq found
next_slot txa try next slot
clc
adc #$100
tax
cmp #$c000 last slot + $100
bne search
lda #$FFFF
sta slot_num store -1 to
bra end indicate FPCP not found
found txa slot number of FPCP
xba
and #$0f strip slot number
sta slot_num save slot number
end short m
lda #0 re-enable internal slot 3 ROM
sta SETINTC3ROM
lab2 lda RDC3ROM wait for internal slot 3
bmi lab2 space to be enabled
tya re-enable other internal
sta SLTROMSEL slot ROM
long m
cli re-enable interrupts
ret 2:slot_num
id_bytes anop
dc h'3838'
dc h'1818'
dc h'01af'
slot_num ds 2
end