mirror of https://github.com/smartykit/apple1.git
75 lines
2.6 KiB
C++
75 lines
2.6 KiB
C++
;
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; Originally designed and written by Daryl Rictor (c)2003-2004
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;
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; Modified by Grant Searle 2007-13
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;
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; Define Registers and Port Pins
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; Acc = R00, R01 (results of multiply command)
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.def Acc = R0 ; Reserved - maths accumulator for multiply operations
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.def Acch = R1 ; "
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.def nibbleTemp= R2 ; Temp storage for 4-bit (nibble) transfer
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.def configByte = R3 ; As read from PORT D at startup
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.set CONFIG_PAL = 7 ; 0xxxxxxx = NTSC, 0xxxxxxx = PAL
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.set CONFIG_8_OR_4_BIT = 6 ; x0xxxxxx = 4 bit, x1xxxxxx= 8 bit
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.set CONFIG_N_TWI = 5 ; xx1xxxxx = 4/8 bit, xx0xxxxx= Two wire
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.set CONFIG_80_CHAR_PER_LINE = 4 ; xxx0xxxx = 40, xxx1xxxx=80
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.set CONFIG_SINGLE_HEIGHT = 3 ; xxxx1xxx = Normal, xxxx0xxx = Double height
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.set CONFIG_BOLD = 2 ; xxxxx0xx = Normal, xxxxx1xx = Bold
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.def currLineAtt = R4 ; Reserved for scanline processing
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.set ATT_80_CHAR_PER_LINE = 0 ; xxxxxxx0 = 40, xxxxxxx1=80
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.set ATT_BOLD = 1
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.set ATT_DBL_TOP = 2 ; xxxx00xx = Normal, xxxx01xx = Double top row, xxxx10xx = Double bottom row
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.set ATT_DBL_BOTTOM = 3
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.def activeLineAtt = R5 ; Font/graphic style currently being used
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.set ATT_DBL_HEIGHT = 2
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.set ATT_GRAPHICS = 7
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.def previousInpt = R6
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.def charUnderCursor = R7 ; character under the cursor
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.def temp1s = R8
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.def temp0s = R9
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.def lastline = R10
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.def line1 = R11
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.def cmdVal = R12
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.def temp = R13 ; General purpose temp
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.def temp2 = R14 ; General purpose temp
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.def temp3 = R15 ; General purpose temp
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;-------------------------------------------------
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.def J = R16 ; scratch 8 bit reg
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.def K = R17 ; scratch 8 bit reg
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.def column = R18 ; hor cursor pos 0-79
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.def row = R19 ; vert cursor pos 0-24
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.def vline = R20 ;\ vertical display line counter 0-261
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.def vlineh = R21 ;/ hi byte of vline counter
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.def chrln = R22 ; display chr line 0 - 199
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.def inpt = R23 ; host input
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.def cursorChar= R24 ; cursor character
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.def cursorClk = R25 ; the cursor blink timer
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; X pair = R26,27
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; Y pair = R28,29
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; Z pair = R30,31
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;
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; X pair used to point to SRAM by refresh routines
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; Y pair used to point to SRAM by HOST processor
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; Z pair used to point to Font data in Program Memory & scrolling
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;PORT pin defs
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.set syncpin = PB0 ; output
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.set ldsrpin = PC3 ; output
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.set ackdpin = PC4 ; output
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.set availpin = PC5 ; input
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.set ntscpin = PD7
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.set datalenpin = PD6
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.set twowireselpin = PD5
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; TWI defs
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.equ TW_SR_DATA_ACK = 0x80 ; x80 10000000 (the previously addressed (SLA + W) data has been received , ACK has been returned
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