51 lines
941 B
ArmAsm
51 lines
941 B
ArmAsm
;; BASIC Cold start entry point
|
|
;; Compute's Mapping the 64 p211
|
|
|
|
basic_cold_start:
|
|
;; Setup BASIC vectors at $0300
|
|
;; Initialise interpretor
|
|
;; Print start up message
|
|
|
|
;; Print coloured part of the message
|
|
ldy #>startup_message
|
|
lda #<startup_message
|
|
jsr print_string
|
|
|
|
|
|
;; Work out free bytes, and display
|
|
jsr basic_do_new
|
|
lda basic_top_of_memory_ptr+0
|
|
sec
|
|
sbc basic_end_of_text_ptr+0
|
|
tax
|
|
lda basic_top_of_memory_ptr+1
|
|
sbc basic_end_of_text_ptr+1
|
|
|
|
jsr print_integer
|
|
|
|
lda #$20
|
|
jsr $ffd2
|
|
|
|
;; Print the rest of the start up message
|
|
ldx #34
|
|
jsr print_packed_message
|
|
|
|
;; jump into warm start loop
|
|
jmp basic_warm_start
|
|
|
|
|
|
startup_message:
|
|
;; Clear the screen
|
|
.byte $93
|
|
;; Vertical bars in different colours
|
|
.byte $1C,$B4
|
|
.byte $9E,$B5
|
|
.byte $1E,$A1
|
|
;; <RVS><WHITE>MEGA<NORMAL>BASIC\r\r
|
|
.byte $12,$05,$4D,$45,$47,$41,$92
|
|
.byte $42,$41,$53,$49,$43
|
|
.byte $20,$56,$32,$2e,$30,$2e,$30
|
|
.byte $0D,$0D
|
|
|
|
.byte 0
|