Specifications

36
SERIAL PORT
SETUP
SELECTIONS DEFAULTS
SET ADDRESS
N (decimal) (Protocol-Specific)
DEVICE ADDRESS FOR MODBUS, DF1, AND ADAM-4000 PROTOCOLS.
ETHERMETER DOES NOT CHECK ADDRESS FOR RANGE VALIDITY.
4 (decimal)
SET PROTOCOL
MB-RTU, MB-ASCII, DF1-FD, DF1-RM, ASCII, DISPLAY,
ADAM (ADAM-VERSION ONLY)
(SELF EXPLANATORY)
MB-RTU
SET BAUD
N (bps)
NOTE: DEVICE CAPABLE OF NON-STANDARD BAUD RATES.
9600
SET SERIALPARAMS
8N1, 7E1, 7O1, 7N2
8N1 (8 Data Bits, No Parity, 1 Stop Bit)
7E1 (7 Data Bits, Even Parity, 1 Stop Bit)
7O1 (7 Data Bits, Odd Parity, 1 Stop Bit)
7N2 (7 Data Bits, No Parity, 2 Stop Bits)
8N1
SET FLOW-CTRL
FIXEDRTS, NULLMODEM, HANDSHAKE, NONE
FIXEDRTS (USE FOR CERTAIN “DUMB” MODEMS & RS-485):
• DELAY BEFORE RESPONSE FOR FIXED TIME,
• THEN RAISE RTS FOR FIXED TIME,
• TRANSMIT DATA
• HOLD RTS HIGH FOR FIXED TIME
NULL-MODEM:
• TRANSMITS IF/WHILE CTS IS HIGH.
• LOWERS RTS IF/WHILE RCV BUFFER FULL.
HANDSHAKE (USE FOR CERTAIN “SMART” MODEMS):
• RAISE RTS WHEN DATA IS READY TO TRANSMIT.
• BUT WAIT FOR CTS RCV’D FROM MASTER BEFORE XMT.
NONE (USE FOR CERTAIN “SMART” MODEMS):
• NO HARDWARE FLOW CONTROL
• ACTIVE WIRES: TXD, RXD, AND GND
NOTE: SOFTWARE FLOW CONTROL IS NOT SUPPORTED.
FIXEDRTS
SET RESP-DELAY-US
N (usecs)
• USED WITH “FIXEDRTS” FLOW CONTROL ONLY.
• TIME DELAY BEFORE RESPONDING TO A REQUEST
BY A MASTER.
• USEFUL FOR TUNING RS-485 OR RADIO-MODEM TIMING.
• IMPLEMENTED IN MULTIPLES OF 834 MICROSECONDS.
0
SET PRE-RTS-US
N (usecs)
• USED WITH “FIXEDRTS” FLOW CONTROL ONLY.
• AFTER RESP-DELAY-US, THIS IS THE TIME DELAY
WHILE HOLDING RTS HIGH.
• USEFUL FOR TUNING RS-485 OR RADIO-MODEM TIMING.
• IMPLEMENTED IN MULTIPLES OF 834 MICROSECONDS.
834
SET POST-RTS-US
N (usecs)
• USED WITH “FIXEDRTS” FLOW CONTROL ONLY.
• AFTER DATA IS COMPLETELY TRANSMITTED, THIS IS
THE TIME DELAY FOR HOLDING RTS HIGH.
• USEFUL FOR TUNING RS-485 OR RADIO-MODEM TIMING.
• IMPLEMENTED IN MULTIPLES OF 834 MICROSECONDS.
0
SET COLL-AVOID-US
N (usecs)
• USED WITH “FIXEDRTS” FLOW CONTROL ONLY.
• IF NON-ZERO, TRANSMITTER WILL WAIT UP TO N
MICROSECONDS FOR DCD TO GO LOW BEFORE
TRANSMITTING.
• USEFUL FOR IMPLEMENTING COLLISION-AVOIDANCE
WITH “DUMB” RADIO-MODEMS.
• IMPLEMENTED IN MULTIPLES OF 834 MICROSECONDS.
0
SET NHALFBYTES
N (halfbytes)
• MODIFIES MODBUS/RTU AND DF1 SERIAL RECEPTION BEHAVIOR.
DURING DATA PACKET RECEPTION, AFTER “N” HALF-BYTE TIME
PERIODS HAVE ELAPSED WITH NO FURTHER DATA RECEIVED, THEN
END-OF-PACKET IS ASSUMED. DOES NOT AFFECT MODBUS/ASCII OR
ADAM-4000 RECEPTION BEHAVIOR.
• MODIFYING THIS SETTING MAY IMPROVE RECEPTION RELIABILITY
WHEN USING AN UNCONDITIONED (EG. BELL-202) RADIO-MODEM.
7
( MODBUS/RTU
DEFAULT =
3.5 BYTE TIMES )