RCA COSMAC Operator's Manual page 17

INTRODUCTION TO UTILITY PACKAGE - UTZ (cont'd)
We present below a further detailed summary of in-
structions for use of UTZ, repeating the information
just presented in a more concise form.
1.
After hitting "RUN UTILITY", hit either CR or LF:
a. For Half Duplex, hit LF.
b. For Full Dupl~x.!hit·CR.
(This sets up the bit-serial timing and specifies echo or not.)
Z. VTZ will return
*
as a prompt.
3. Following
*,
VTZ ignores all characters until one
of ?, $, or ! is typed in. Then:
4. Following? or ! must be M. Then VTZ waits for a hex
character. It then assembles an address (if more than
four hex digits are typed, only the last four are used).
Next, a space is required.
a. For?M addr 6 a hex count must follow (again, only
the last four digits are kept), and the command
is terminated by CR.
b. For!M addr 6 data must follow. An even number of
hex dIgIts IS required. Before each hex pair ar-
bitrary garbage is allowed, except for a CR, comma,
or semicolon. CR terminates the command, unless
immediately preceded by comma or generally preceded
by a semicolon.
i.
In case of comma CR the user should insert
his own LF, and
uTz
continues to accept data.
This is a form of line continuation.
ii. In case of a semicolon, all following characters
are ignored until the CR is typed. Then the
user again should provide LF, and VTZ continues
as if he had begun a new command with !M --
i.e., optional garbage, then a starting address
must follow, then a space, and then data.
iii. The!M command can use as many continuation
lines as needed, mixed between the two types
if desired, and finally terminating with a CR
not preceded by comma or semicolon.
S. Following $ must be P, and then the starting address
(last four digits used if more than four typed in).
(If no address is entered, 0 is assumed.) Program
execution begins at this location using RO as program
counter.
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