Apple-2-SW/apple2_hgr_font_tutorial
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Add missing ORG

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michaelangel007 2016-01-11 02:40:47 -08:00
parent 329867e140
commit a40a68418d
1 changed files with 61 additions and 48 deletions
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@ -865,9 +865,9 @@ Recall we'll re-use our existing font drawing code `_DrawChar` at $0352:
```assembly ```assembly
ORG $0352 ORG $0352
352: _DrawChar 352: _DrawChar
352:A2 00 LDX #0 ; next instruction is Self-Modifying! 352:A2 00 LDX #0 ; next instruction is Self-Modifying!
354:BD 00 00 _Font LDA $0000,X ; A = font[ offset + i ] 354:BD 00 00 LoadFont LDA $0000,X ; A = font[ offset + i ]
357:91 F5 STA (TmpLo),Y ; screen[col] = A 357:91 F5 STA (TmpLo),Y ; screen[col] = A
359:18 CLC 359:18 CLC
35A:A5 F6 LDA TmpHi 35A:A5 F6 LDA TmpHi
@ -980,6 +980,7 @@ Let's fix it up to print the hex value of the current character we are inspectin
; FUNC: DrawHexByte( c ) = $103C ; FUNC: DrawHexByte( c ) = $103C
; PARAM: A = byte to print in hex ; PARAM: A = byte to print in hex
103C: DrawHexByte
103C:48 PHA ; save low nibble 103C:48 PHA ; save low nibble
103D:6A ROR ; shift high nibble 103D:6A ROR ; shift high nibble
103E:6A ROR ; to low nibble 103E:6A ROR ; to low nibble
@ -991,6 +992,7 @@ Let's fix it up to print the hex value of the current character we are inspectin
; FUNC: DrawHexNib() = $1048 ; FUNC: DrawHexNib() = $1048
; PARAM: A = nibble to print as hex char ; PARAM: A = nibble to print as hex char
1048: DrawHexNib
1048:29 0F AND #F ; base 16 1048:29 0F AND #F ; base 16
104A:AA TAX ; 104A:AA TAX ;
104B:20 66 03 JSR HgrToTmpPtr 104B:20 66 03 JSR HgrToTmpPtr
@ -998,7 +1000,7 @@ Let's fix it up to print the hex value of the current character we are inspectin
1051:C8 INY ; IncCursorCol() 1051:C8 INY ; IncCursorCol()
1052:20 3B 03 JSR DrawCharCol 1052:20 3B 03 JSR DrawCharCol
1055:60 RTS 1055:60 RTS
ORG $358 ORG $0358
1058:30 31 32 33 NIB2HEX ASC "0123456789ABCDEF" 1058:30 31 32 33 NIB2HEX ASC "0123456789ABCDEF"
105C:34 35 36 37 105C:34 35 36 37
1060:38 39 41 42 1060:38 39 41 42
@ -1034,9 +1036,9 @@ Let's use IncCursorCol() to automatically advance the cusor. We'll also add a s
; Must start at every 8 scanlines. ; Must start at every 8 scanlines.
; OUTPUT: The Y-Register (cursor column) is automatically incremented. ; OUTPUT: The Y-Register (cursor column) is automatically incremented.
ORG $0310 ORG $0310
310 PrintChar 0310: PrintChar
310:20 3B 03 JSR DrawCharCol 0310:20 3B 03 JSR DrawCharCol
313:4C 70 03 JMP IncCursorCol 0313:4C 70 03 JMP IncCursorCol
``` ```
And the new code to draw a space before the hex num: And the new code to draw a space before the hex num:
@ -1050,6 +1052,7 @@ And the new code to draw a space before the hex num:
; FUNC: DrawHexByte( c ) ; FUNC: DrawHexByte( c )
; PARAM: A = byte to print in hex ; PARAM: A = byte to print in hex
1041: DrawHexByte
1041:48 PHA ; save low nibble 1041:48 PHA ; save low nibble
1042:6A ROR ; shift high nibble 1042:6A ROR ; shift high nibble
1043:6A ROR ; to low nibble 1043:6A ROR ; to low nibble
@ -1061,11 +1064,12 @@ And the new code to draw a space before the hex num:
; FUNC: $1048 = DrawHexNib() ; FUNC: $1048 = DrawHexNib()
; PARAM: A = nibble to print as hex char ; PARAM: A = nibble to print as hex char
1048: DrawHexNib
104D:29 0F AND #F ; base 16 104D:29 0F AND #F ; base 16
104F:AA TAX ; 104F:AA TAX ;
1050:BD 58 10 LDA $1058,X ; nibble to ASCII 1050:BD 58 10 LDA NIB2HEX ,X ; nibble to ASCII
1053:4C 10 03 JMP PrintChar ; 1053:4C 10 03 JMP PrintChar ;
1058:30 31 32 33 ASC "0123456789ABCDEF" 1058:30 31 32 33 NIB2HEX ASC "0123456789ABCDEF"
105C:34 35 36 37 105C:34 35 36 37
1060:38 39 41 42 1060:38 39 41 42
1064:43 44 45 46 1064:43 44 45 46
@ -1190,11 +1194,12 @@ Enter in:
Now we can print a char at any location: Now we can print a char at any location:
```assembly ```assembly
ORG $1100 ORG $1100
1100:A9 41 LDA #41 ; A-register = char DrawXY
1102:A0 01 LDY #1 ; Y-register = col 1 (2nd column) 1100:A9 41 LDA #41 ; A-register = char
1104:A2 02 LDX #2 ; X-register = row 2 (3rd row) 1102:A0 01 LDY #1 ; Y-register = col 1 (2nd column)
1106:4C 20 03 JSR DrawCharColRow 1104:A2 02 LDX #2 ; X-register = row 2 (3rd row)
1106:4C 20 03 JSR DrawCharColRow
``` ```
Enter in: Enter in:
@ -1217,13 +1222,14 @@ We could map the X-register to the natural column (x-axis), and the Y-register t
; FUNC: SetCursorColRowYX() ; FUNC: SetCursorColRowYX()
; PARAM: Y = col ; PARAM: Y = col
; PARAM: X = row ; PARAM: X = row
ORG $0379 ORG $0379
379:20 28 03 JSR SetCursorRow 379: SetCursorColRowYX
37C:18 CLC 379:20 28 03 JSR SetCursorRow
37D:98 TYA 37C:18 CLC
37E:65 F5 ADC $F5 37D:98 TYA
381:85 F5 STA $F5 37E:65 F5 ADC $F5
383:60 RTS 381:85 F5 STA $F5
383:60 RTS
``` ```
Or are we stuck? Since we're using a function to calculate the destination address let's fix the order. Or are we stuck? Since we're using a function to calculate the destination address let's fix the order.
@ -1233,17 +1239,17 @@ We'll need to change the `X` offset in SetCursorColRowXY() to `Y`;
; FUNC: SetCursorColRow2( row ) = $0328 ; FUNC: SetCursorColRow2( row ) = $0328
; PARAM: Y = row ; PARAM: Y = row
; NOTES: Version 2 ! ; NOTES: Version 2 !
328: ORG $0328 328: ORG $0328
328: SetCursorColRow2 328: SetCursorColRow2
328:B9 00 64 LDA $6400,Y ; changed from: ,X 328:B9 00 64 LDA HgrLoY,Y ; changed from: ,X
32B:18 CLC 32B:18 CLC
32C:65 E5 ADC $E5 32C:65 E5 ADC HgrLo
32E:85 F5 STA $F5 32E:85 F5 STA TmpLo
330:B9 18 64 LDA $6418,Y ; changed from: ,X 330:B9 18 64 LDA HgrHiY,Y ; changed from: ,X
333:18 CLC 333:18 CLC
334:65 E6 ADC $E6 334:65 E6 ADC HgrHi
336:85 F6 STA $F6 336:85 F6 STA TmpHi
338:60 RTS 338:60 RTS
``` ```
And change the low byte to add `X` instead: And change the low byte to add `X` instead:
@ -1253,11 +1259,13 @@ And change the low byte to add `X` instead:
; PARAM: X = col ; PARAM: X = col
; PARAM: Y = row ; PARAM: Y = row
; NOTES: Version 2 ! ; NOTES: Version 2 !
379:20 28 03 JSR SetCursorRow ORG $0379
37C:18 CLC 379: SetCursorColRow2
37D:88 TXA ; changed from: TYA 379:20 28 03 JSR SetCursorRow
37E:65 F5 ADC $F5 37C:18 CLC
381:85 F5 STA $F5 37D:88 TXA ; changed from: TYA
37E:65 F5 ADC $F5
381:85 F5 STA $F5
383:60 383:60
``` ```
@ -1269,18 +1277,19 @@ This is a little clunky but it is progress. Let's write the new SetCursorColRow(
; PARAM: Y = row to draw at; $0 .. $17 (Rows 0 .. 23) (not modified) ; PARAM: Y = row to draw at; $0 .. $17 (Rows 0 .. 23) (not modified)
; NOTES: Version 3! X and Y is swapped from earlier version! ; NOTES: Version 3! X and Y is swapped from earlier version!
; [$F5] = HgrLoY[ Y ] + ScreenLo + X ; [$F5] = HgrLoY[ Y ] + ScreenLo + X
ORG $0379 ORG $0379
379:86 F5 STX $F5 379: SetCursorColRow
37B:B9 00 64 LDA HgrLoY,Y ; HgrLoY[ row ] 379:86 F5 STX TmpLo
37E:18 CLC 37B:B9 00 64 LDA HgrLoY,Y ; HgrLoY[ row ]
37F:65 E5 ADC $E5 37E:18 CLC
381:65 F5 ADC $F5 ; add column 37F:65 E5 ADC HgrLo
383:85 F5 STA $F5 381:65 F5 ADC TmpLo ; add column
385:B9 18 64 LDA HgrHiY,Y ; HgrHiY[ row ] 383:85 F5 STA TmpLo
388:18 CLC 385:B9 18 64 LDA HgrHiY,Y ; HgrHiY[ row ]
389:65 E6 ADC $E6 388:18 CLC
38B:85 F6 STA $F6 389:65 E6 ADC HgrHi
38D:60 RTS 38B:85 F6 STA TmpHi
38D:60 RTS
``` ```
Enter in: Enter in:
@ -1299,6 +1308,7 @@ Now that we have the basic print char working lets extend it to print a C-style
; PARAM: X = High byte of string address ; PARAM: X = High byte of string address
; PARAM: Y = Low byte of string address ; PARAM: Y = Low byte of string address
ORG $038E ORG $038E
38E: DrawString
38E:84 F0 STY $F0 38E:84 F0 STY $F0
390:86 F1 STX $F1 390:86 F1 STX $F1
392:A0 00 LDY #0 392:A0 00 LDY #0
@ -1314,6 +1324,8 @@ And our example to verify that it works:
```assembly ```assembly
; FUNC: DemoDrawString() ; FUNC: DemoDrawString()
ORG $1200
1200: DemoDrawString
1200:A2 03 LDX #3 ; col = 3 1200:A2 03 LDX #3 ; col = 3
1202:A0 02 LDY #2 ; row = 2 1202:A0 02 LDY #2 ; row = 2
1204:20 79 03 JSR SetCursorColRow 1204:20 79 03 JSR SetCursorColRow
@ -1489,6 +1501,7 @@ And here is the assembly:
; $6000.$63FF Font 7x8 Data ; $6000.$63FF Font 7x8 Data
; $6400.$642F HgrLoY, HgrHiY table for every 8 scanlines ; $6400.$642F HgrLoY, HgrHiY table for every 8 scanlines
ORG $1300 ORG $1300
1300: CopyTextToHgr
1300:A9 00 LDA #0 1300:A9 00 LDA #0
1302:85 F3 STA row 1302:85 F3 STA row
1304:85 E5 STA $E5 1304:85 E5 STA $E5