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; ----------------------------------------------------------------------------
; Initialization callback. The OS will call this on coldstart (or would do,
; if the driver were in ROM), and also on warmstart (because we stole the
; DOSINI vector).
; This routine is also the first thing that gets called by the mainline
; init code. Its job is to install COL80 in the handler table at HATABS.
; Actually the handler is first installed as X:, then the main init code
; fixes this up to E: unless the user is holding down SELECT. This allows
; the user to toggle between the 40-column ROM E: and COL80 without doing
; a full reboot. No idea if this was a documented feature or something the
; author used for development/debugging.
col80_init:
ldy #$00
next_hatab_slot:
lda HATABS,y
beq register_x_handler
iny
iny
iny
cpy #$20
bcc next_hatab_slot
jmp return_success
register_x_handler:
lda #$58
sta HATABS,y
lda #<col80_vector_tab
iny
sta HATABS,y
lda #>col80_vector_tab
iny
sta HATABS,y
jmp return_success
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