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reg pg=00 pc=c00c ps=0023 dt=00 sp=027f a=ff00 b=0000 x=027f y=0017 dpr=0000
0000100..0000100 00
0000200..000020f 54 48 49 53 20 49 53 20 4d 45 53 53 41 47 45 20
0000210..000021f 41 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Let's look at the registers to verify that the stack pointer was properly
initialized. Type:
U> reg
You will see:
Notice that sp contains 27f hex.
Verify that the input area command byte was cleared during
initialization.
Type:
U> m -db 100
You will see:
The input byte location was successfully cleared.
Now we will use the emulator features to make the program work.
Remember that the program writes specific messages to the output area
depending on what the input byte location contains. Type:
U> m 100=41
This modifies the input byte location to the hex value for an ASCII
"A". Now let's check the output area for a message.
U> m 200..21f
You will see:
These are the ASCII values for MESSAGE_A.
Repeat the last two commands twice. The first time, use 42 instead of
41 at location 100 and note that MESSAGE_B overwrites
MESSAGE_A. Then try these again, using any number except 00, 41,
or 42 and note that the INVALID_INPUT message is written to this
area.
Getting Started 2-21
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