6502
/
6502-emulator
mirror of https://github.com/tdinucci/6502-emulator.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

Update README.md

This commit is contained in:
Tony Di Nucci 2019-04-26 17:36:54 +01:00 committed by GitHub
parent 857e1ac107
commit b44a511ab2
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 4 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
README.md
View File

@ -41,6 +41,8 @@ There is 64KB of memory and this is broken into
Resolution of the "attached display" is 64 * 64, so 4096 bytes. Each "pixel" is blown up to be 8 pixels in size so things are nice and blocky.
Writing a byte to 0xE000 will draw a pixel at the top left and at byte at 0xF000 will display at the bottom right.
Each pixel can be one of 256 colours where bits:
* 0-1 are blue
@ -51,6 +53,8 @@ Each pixel can be one of 256 colours where bits:
The last key pressed is stored to 0xF001 and it's up to your programs to clear this out after reading if you don't want to repeatedly read the same keypress.
SDL is used for reading key presses and the code for each key is https://wiki.libsdl.org/SDLScancodeLookup. Only key presses where the code is <= 0xFF are logged.
## Sample
The _sample/draw.s_ file contains well commented 6502 assembly code for a simple program which allows you to draw multi-coloured lines with your cursor keys. What fun!