FANUC Robotics America GFK-1535A - Manual (Page 31)

2-12 VersaMax™ System Genius® Network Interface Unit User's Manual – November 2000 GFK-1535A
2
Setting the SBA and Baud Rate
Open the clear protective door by pulling upward at the indentation in the side of
the NIU. Use a 2.44mm (3/32in) flat screwdriver to adjust the rotary switches.
(Refer to the heading Special Switch Settings if the NIU is being configured using
datagrams or for information about upgrading the NIU firmware).
0
1 0
0
7
6 4
5
8
9 1
1
BAUD
RATE
SBA
X10
3
2
3
2
3
2
SBA
X1
N
N
A
U
Baud Rate
Serial Bus
Address
Select the serial bus address with the two upper rotary switches, SBA X10 (for the
tens digit) and SBA X1(for the ones digit). Each device on a bus must have a unique
serial bus address in the range 0 - 31.
Select the baud rate to match that used by the other devices on the bus by setting the
bottom rotary switch: (3) 153.6 Kbaud extended, (2) 153.6 Kbaud standard, (1)
76.8 Kbaud, or (0) 38.4 Kbaud.
Cycle power to the NIU after changing the switch settings.
Selecting a Baud Rate
All devices on a bus must use the same baud rate.
If the cable length is between 4500 and 7500 feet, you must select 38.4 Kbaud. This
data rate only supports a maximum of 16 devices on the bus.
If the cable length is between 3500 and 4500 feet, select 76.8 Kbaud.
If cable length is between 2000 and 3500 feet, select 153.6 Kbaud extended.
If the cable length is less than 2000 feet, either 153.6 Kbaud standard or 153.6
Kbaud extended can be used. 153.6 Kbaud extended is recommended, especially if
the system will include a dual bus. In noisy environments, 153.6 Kbaud extended
provides improved noise immunity with little effect on bus scan time.
Selection of an appropriate baud rate for the system may also be determined by the
type of cable used. For more information, see Selecting a Cable Type.