Apple-2-SW/apple2_hgr_font_tutorial
1
0
Fork 0
mirror of https://github.com/Michaelangel007/apple2_hgr_font_tutorial.git synced 2024-11-25 07:32:25 +00:00
Code Issues Projects Releases Wiki Activity

Added pic 16

Browse Source
This commit is contained in:
michaelangel007 2016-01-10 15:50:57 -08:00
parent e68ff05033
commit bd41b49b19
2 changed files with 7 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
README.md
View File

@ -1,6 +1,6 @@
#Apple ]\[ HGR Font Tutorial
Revision: 9, Jan 10, 2016.
Revision: 10, Jan 10, 2016.
# Table of Contents
@ -1097,7 +1097,7 @@ We'll split the table of addresses into Low and High bytes for easier access. We
This is our mini HGR Y Address look-up table. "Funny" that it has 24 entries -- the same height as our text screen. :-)
Enter these bytes:
Enter these bytes (or `bload hgrtable.bin`):
Our `HgrLo` table:
@ -1111,6 +1111,8 @@ Our `HgrHi` table:
6420:00 00 01 01 02 02 03 03
6428:00 00 01 01 02 02 03 03
To save this AppleWin press `F7`, at the debugger console `bsave "hgrtable.bin",6400:642F`, press `F7`.
To select which row to draw at we'll pass that in the X register to our DrawCharColRow() routine:
```assembly
@ -1159,6 +1161,9 @@ Enter in:
1100:A9 41 A0 01 A2 02 4C 20 03
1100G
![Screenshot 16](pics/hgrfont_16.png?raw=true)
## Natural Params CursorColRow()
Unfortunately, our usage of the X and Y registers are not intuitive. This is due to the limited addressing modes of the 6502. :-/ If the 6502 had a symmetrical indirect zero-page X addressing mode:

BIN
pics/hgrfont_16.png Normal file
View File

Binary file not shown.
Side by Side

After

Width:  |  Height:  |  Size: 430 B