Product specifications

4007 LD HL,DATA
400A LD DE,COPY
400D LD BC,5
4010 LDIR
4012 RET
4013 DATA: DB 12,£34,"LOW''
4010 COPY:DS 5
4011 RET
Symbols..
DATA 4013 COPY 4018
Suppose we wanted to modify the program to transfer only the first two bytes. We
would change the line at 400D from LD BC,5 to LD BC,2.
To do this type E £400D and RET.
This will put us in edit mode and display the line to be edited.
Use the cursor along the line with the arrow keys until it is over the letter "5", then we
press the "2" key to change the number followed by RET to store the line away. The
line is now safe in memory and the next line will be presented for editing.
To quit edit mode type CLS followed by RET.
This will leave the assembler ready to accept the next directive.
There is another way of specifying lines in the assembler code without having to use
the address of the instruction.
Suppose we wanted to alter the 12 in line 4013 of the previous example. That line has
an associated label "DATA", so we can use this instead of the address.
Type E DATA and RET.
This has exactly the same effect as E £4013 and RET.
To leave the assembler press CLS and RET. This will bring you back to BASIC.
Now type LIST or L. in BASIC and you will see your assembler code program appear
as a BASIC line. If you already had or now add some lines of BASIC you will find the
code line takes its place just like any normal BASIC line would.
NB:- as your BASIC program is added to or edited the code line will move about in
memory. As most machine code is location dependent it will become necessary to re-
assemble your code.
To do this type:... ASSEM 10