Operator`s manual

E-1
E
E. Command Codes (AVM-510A)
Introduction
This appendix describes the RS-232 protocol between the AVM-510A Series Automated Video
Monitors (AVM-510A) and a Personal Computer (PC).
Guidelines
•
Letters with ‘ ’ (single quotes) are literal and case sensitive. For example, an ‘a’ is the lower case
ASCII letter a, with a decimal value of 97. In general, the case of the letters is significant and must
be followed.
•
<CR> means a carriage return. This is ASCII decimal code 13 or 0xD hex. It is used to terminate
all text strings, either sending or receiving.
•
Numbers inside [ ] represent an inclusive range. For example, [0…10] means any value from and
including 0 up to and including 10.
•
Spaces must not be used unless explicitly stated. A needed space is indicated by an underscore _.
•
All data received or transmitted except raster dumps are ASCII values. For example, to send a
value of 129, you must sent three characters: a ‘1’, a ‘2’, and then a ‘9’. This is not the same as
sending a binary 129 value.
•
Requests for information usually begin with a lower case letter. Control functions that change
things usually begin with an upper case letter.
Placeholders
•
S. .S is used to denote a string of characters. The string contains ASCII characters, possibly
including spaces, but nothing below the ASCII binary value of a space (32), that is, no control
codes.
•
H is generally used to represent a hexadicimal digit from [0. . F].
•
N is generally used to represent a decimal digit from [0. .9]. [N. .N] is used to represent an
arbitrary number of successive digits that make up a decimal number.
•
Bit 0 is always the Least Significant Bit (LSB).