Apple-2-SW/apple2_hgr_font_tutorial
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Add more Listing and Demo headers

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Michaelangel007 2016-01-27 10:24:42 -08:00
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README.md
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@ -1,6 +1,6 @@
#Apple ]\[ //e HGR Font 6502 Assembly Language Tutorial
Revision: 48, Jan 27, 2016.
Revision: 49, Jan 27, 2016.
# Table of Contents
@ -1411,6 +1411,8 @@ The **lateral** thinking is to _use partial results_.
Let's code this up:
Listing 6:
```Assembly
; FUNC: DrawCharCol( c, col ) alias _DrawChar2
; PARAM: A = glyph to draw
@ -1507,6 +1509,8 @@ We now have the ability to print any of the 128 ASCII characters!
Let's verify this by writing a character inspector. We'll use the arrow keys to select the glyph and ESC to exit.
Listing Demo2a:
```assembly
; FUNC: DemoCharInspect()
KEYBOARD EQU $C000
@ -1574,6 +1578,8 @@ We now have an ASCII char inspector!
Let's fix it up to print the hex value of the current character we are inspecting:
Listing Demo2b:
```assembly
ORG $1010
1010:20 3C 10 JSR Patch1
@ -1642,6 +1648,8 @@ And now we have our own DrawHexByte() function.
Let's add a space after the character but before the hex value to improve readability of the output. The new code is:
Listing Demo2c:
```assembly
ORG $1010
1010:20 37 10 JSR Patch2
@ -1756,6 +1764,8 @@ Our `HgrHiY` table:
To select which row to draw at we'll pass that in the X register to our DrawCharColRow() routine:
Listing 7:
```assembly
; FUNC: SetCursorRow( row )
; PARAM: X = row to draw at; $0 .. $17 (Rows 0 .. 23) (not modified)