Briel Computers Replica I, Setup And Users Manual Setup And Users Manual, Page: 26 / 33

Replica 1 TE Users Manual
© Briel Computers 2007 page
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Chapter 7: Using the Krusader Assembler
Krusader is a powerful assembler written by Ken Wessen for the replica 1. This assembler makes programming
the 6502 processor in the replica 1 a breeze. No hand converting mnemonic instructions to hex then manually
entering them in the Woz monitor. Now you can program using mnemonic instructions, assemble and run your
program right from the assembler. To enter the assembler, type in:
F000R [return]
The program will begin and the authors name and current revision will appear. Next line will display a ‘?’ with
the cursor next to it. Type ‘N’ to enter a new program. The assembler will now display ‘000’ for the first line.
Let’s enter the program listed in the Krusader as an example program.
000 is now displayed. Press space bar to skip the first field used for naming code blocks. The assembler tabs
over to the next field. Type LDA #’A’ [return] ;
001
is now displayed. Then type
LOOP
then press space bar to tab to the next field. Type
JSR $FFEF
[return]. Type in the rest as shown:
002 CLC
003 ADC #$1
004 CMP #’Z’+1
005 BNE LOOP
006 RTS
Once you have entered in the source code, type L to list out the code, and then A to assemble it. To run your
code type
R $300
. The program will run and output the string:
ABCDEFGHIJKLMNOPQRSTUVWXYZ
Once the program finishes with the RTS command it will return to the Krusader assembler shell.
To learn more on how to program using Krusader, refer to the Krusader owner’s manual or visit the Krusader
web site at:
http://school.anhb.uwa.edu.au/personalpages/kwessen/apple1/Krusader.htm