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BEKODO 00 FE
6V0O1 00
EKOO0O FF - š

The contents of 6000 are shown as FF,

To summarize the M command so far, you can seguentially step

the value 00, (the value was changed immediately you typed the
second 0) you can change it again if you wish,

So, if you enter an incorrect value, and realise what y0u have done
before you press ENTER, you can correct YOUur mistake without
having to specify the address again. in fact, You can make only two
sttempts at entering a value before the routine returns you to the

prompt and cursor, when you will have to type M to re-enter tho M '
command.

Remember, that in the M command, ENTER only has the effect of
Stepping on to the next memory location, whereas in other

Commands (where applicable) ENTER causes the Operation to be
executed,

Imagine that you have just entered a machine Code routine from,
say 6000 to 6200, and you realise that you need to change the value
of one byte somewhere near the middle of the routine, but you do
not know the precise address, You could spend a long time guessing
addresses and looking at their Contents, or repeatedly pressing
ENTER until you find the right byte. But if You type M, to re-enter
the M command, and look at the Contents of an address somewhere
near the beginning of the rOutine, then press ENTER, and hold it
pressed, after about 1% seconds the screen will start scrolling guite
fast, and will rapidly display successive locations until you release
ENTER. In this way you can guickly scan through a routine until
you find the byte You are looking for. To effect the alteration,
having released ENTER, you wili again have to type M xxxx to
re-enter the M command at the Correct address, and then change the '
Contents of that address,

..

The 'M' command, (and the $ command, described on page 18) are
the only commands that usa the repeating key facility.

X — Escape

The X command allows YOU to escape from a command mode and
returns you to the monitor key scan routine, .

t

Type X . :
The screen will seroli, and the prompt and cursor will reappear on
the bottom line of the screen. You can now enter any of the
MONITOR commands. All command routines, with the exception
of R (display registers) and K (breakpoint restore), will accept X as
8n escape command at any time up to the point of execution.

1 — Insert

If, having written a machine code routine, you find it necessary to
add extra instructions in the middle of that routine, the Insert
command (1) allows you to insert up to 255 bytes at any point, and
automatically moves up memory a specified area of RAM by the
number of bytes you wish to insert.

The Insert command takes the form "| aaaa bbbb nn" where | is the
Insert command mode, aaaa is the Hex address of the first byte of
the insertion, bbbb is the Hex address of the highest byte in RAM of
the block of memory to be moved, and nn is the number of bytes to
be inserted, in Hex,

Example ;

Type X to restore the prompt and cursor to the bottom line,
and then, using the M command, enter the following
Consecutive values into memory:

6000 00

6001 01

6002 02 >z

600303  , id
etc.

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