19
4. Numeric data required with the RCD command to specify
counter or preset to be read. Up to eight numeric charac-
ters are required for some commands. Most commands
do not require any numeric characters (see pages 19
through 21 for list of all commands).
5. Two digit hexadecimal checksum of the ASCII values of
the ID number, command, and any required numeric
characters. Required for all transmissions to the control.
Checksum Calculation:
The checksum is the last two hexadecimal characters —
7A. Upper or lower case letters may be used. The > start
character and carriage return are not used in calculation.
6. ASCII carriage return (13 decimal). Required at the end
of all commands.
SERIAL RESPONSE FORMAT
The counter does not respond to a command unless the
transmitted ID number matches its programmed ID number.
If the ID numbers match and the command and checksum
are valid, the control executes the command and transmits a
response as shown below:
A [data] [checksum] (cr) where:
A is the acknowledge character (ASCII 65) sent when any
valid command is received and executed.
[data] is sent in response to the RCD, RDV, or RPI com-
mands which request data. Data is not transmitted for
other commands.
[checksum] is sent only when data is requested (RCD, RDV
or RPI commands). The checksum is calculated by add-
ing the ASCII values of all preceding characters (includ-
ing spaces), but excluding the acknowledge character
"A". The checksum is the two least significant digits of this
sum in hexadecimal.
(cr) is the ASCII carriage return (13 decimal). Transmitted at
the end of all responses.
EXAMPLES:
A(cr)
No data requested
ACT 337914 52(cr)
Count data requested
If the ID numbers match but the command is not valid or
cannot be executed, the counter ignores the command and
SERIAL COMMAND/RESPONSE FORMAT
responds by sending an ASCII “N” (not acknowledged)
followed by a one character error code and a carriage return.
Error Codes:
00 - Power up Error — When power is applied to the unit, or
the program mode is exited, the unit performs a power
up self test. The first valid command received by the
unit following the self test is not executed and not
acknowledged.
10 - Lock input is on — cannot change preset values or
enter serial program mode until lock input is removed.
02 - Checksum error — received checksum does not match
calculated checksum.
01 - Command not found in table or invalid command —
WPI, RPI, XSP received when not in serial program
mode.
05 - Invalid data — incorrect number of digits or illegal
character received in data field.
11 - Preset edit in progress on keyboard — serial preset
cannot be sent if preset is being changed on the
keyboard.
12 - Command is valid for this family but not this counter or
command is not valid with this program configuration —
cannot change output time if output is set to latch.
13 - Keyboard programming mode is active — cannot enter
serial program mode if in keyboard program mode.
EXAMPLES:
N05(cr) Invalid data
N10(cr) Lock input is on
SERIAL RUN-MODE COMMANDS
RCD(n) — Read Counter Data
This command must be followed by a number (n) from 0 to 7.
The number determines which value the counter sends. The
requested value is preceded by a two character counter or
preset abbreviation. The counter formats its response in a 12
character field. The counter sends any programmed decimal
points in the correct location. Leading zeros are sent as
spaces.
EXAMPLE COMMAND: >1BRCD37F(cr) Reads rate indi-
cator from unit 27.
EXAMPLE RESPONSES:
(n) Value Sent
Response Formats with Different
Decimal Points
0
Main counter
ACT 123456 4C(cr)
1
Batch counter
ABT 123456 4B(cr)
2
Totalizer
AT 12345678 58(cr)
3
Rate
ART 123456 5B(cr)
4
Preset 1
AP1 123456 36(cr)
6
Batch Preset
APB 123456 47(cr)
0 A R C D 2
48 + 65 + 82 + 67 + 68 + 50 = 380 (dec.)
