Instruction manual

SERIAL INTERFACE
6-3
Instruction Format
In general, the format used as the command string for serial input is as
follows:
1 2 3 4
DATA — ADDRESS — ACTION CODE — <LF>
1. DATA
– is a two character hexadecimal code (in ASCII) which is
written to the control register that is being addressed, and is used
during a Write Action only.
2. ADDRESS
– is a one to three character hexadecimal code (in
ASCII) that selects the memory location which will be acted upon.
3. ACTION CODE
– is a single character which is used to define the
Remove Control Action as shown below:
NOTE: ALL ACTION CODES FOR THE 361T MUST BE SENT
AS CAPITAL (UPPERCASE) LETTERS.
G [Go] is the ASCII character sent to the 361 to release it to operate as
instructed after the "LF" (or "CR" is received.
NOTE: The reason for the "G" command is that when the
361T senses that data is being received on the serial input,
it stops normal operation and only allows the serial input to
modify or monitor keys and control registers, until a "G"
Action Code is given to return the 361T to normal
operation.
I [INTERROGATE] reads the external RAM memory from the first
Address to the last Address, and sends the Data value(s) out the
Transmit line of the I/O port in the following format: ##CR(LF).
The first and last Address must both be designated a 3 hexadecimal
characters in the command string. If the last Address is not sent or is
a lower Address than the first Address, then only the first Address is
read.
Command String # # #
# # # I——Action Code
│ │
Last Address First Address