CHAPTER 1

Allen-Bradley 6008-SV

VMEbus I/O Scanner

The VMEbus I/O Scanner physically resides in a VME chassis Input Output Controller (IOC), and acts as a master for an Allen Bradley subnet in an EPICS control system. The address of the VMEbus I/O Scanner corresponds to the LINK number in an Allen-Bradley / EPICS subnet. Up to two VMEbus I/0 Scanners (LINK 0 and LINK 1) may be used in one VME chassis IOC. In an EPICS control system, one VMEbus I/O Scanner has the ability to be the master for up to 8 Allen Bradley slave nodes, including Remote I/O Adapters in Allen Bradley 1771 Series I/O Chassis, or Allen Bradley RediPANEL Pushbutton Modules, both commonly used in an EPICS control system. In an Allen-Bradley / EPICS subnet the addresses of the slave nodes are referred to as the ADAPTER number.

VMEbus 6008-SV I/O Scanner Strapping

Refer to figure 1.1 when strapping the VMEbus I/O Scanner. J2, J6, J7, and J8 are factory mandated settings and should not be altered from their illustrated positions. J1, J4, and positions 1 - 4 of J5 are set as illustrated so that the VMEbus I/O scanner conforms to standard 24bit supervisory access data addressing, the mode used in an EPICS control system. J3, and positions 5 - 8 of J5 are set for the proper base address of a VMEbus I/O scanner in an EPICS control system. They should be inserted as illustrated in figure 1.1 with the exception of J5 position 8. This jumper should be inserted for a VMEbus I/O scanner module used as LINK 0, and removed for a VMEbus I/O scanner module used as LINK 1.

VMEbus 6008-SV I/O Scanner Installation

Power Requirements

The Allen-Bradley VMEbus I/O Scanner may be installed in any VME chassis IOC. Before Installation, calculate the power requirements of the modules currently in the VME chassis IOC. Add to that 2.5A @ 5V DC, the current required by the VMEbus I/O Scanner. Check to be sure that this combined current requirement does not exceed the current driving ability of the VME chassis IOC power supply.

Module Location in the VME chassis Input Output Controller (IOC)

The VMEbus I/O Scanner is a 6U, double height VME board which may occupy any slot but the first slot in a VME chassis IOC, this slot is commonly occupied by the VME processor module.

Module Insertion

Before a module is inserted into a VME chassis IOC, be sure that the power to the IOC is shut off. As always, be sure that "bringing down" this specific IOC will not have detrimental effects on any part of the control system serviced by this particular IOC. To insert the module, place it in the plastic tracks on the top and bottom of the VME chassis IOC. Slide the module into the IOC until the module comes in contact with the backplane connectors. Do not force the module in, instead apply firm and even pressure on the module to seat it properly on the backplane connectors. Tighten the screws at the top and bottom of the face panel of the VMEbus I/O Scanner (be sure not to over-tighten) so that the I/O Scanner remains firmly in place in the VME chassis IOC.

VMEbus 6008-SV I/O Scanner Wiring Connection

Connection between the VMEbus I/O Scanner master, and the Allen-Bradley subnet slave modules such as the remote I/O adapters or RediPANELs should be made via shielded twin-axial cable. The use of Belden 9463 J22 304.8MTR BLUSTG is recommended. This cable has the following specifications.


78 OHM TWINAXIAL CABLE
2 CONDUCTOR
20 AWG (.52 sq. mm) 7x#28 (.08 sq. mm) Tinned Cu
.0185" (.47mm) SOLID PE DIALECTRIC
BELDFOIL 100% + Tinned Cu BRAID 57%
.032" (81mm) PVC JACKET - .243" O.D.
SURFACE PRINTED
(UL) TYPE CM
USE: COMMUNICATION CIRCUITS IN ACCORDANCE WITH NEC ARTICLE 800
AWM STYLE 2582
60C 150V
The VMEbus I/O Scanner should be used with the supplied connector that fits into JK1 of the VMEbus I/O Scanner. The wires should be inserted into the connector so that the corresponding connection to JK1 will appear as in figure 1.2.

VMEbus 6008-SV I/O Scanner Use

The front panel of the VMEbus I/O scanner contains four LEDs which indicate the status of the I/O Scanner. The PWR (power) LED is lighted green when power (5V) is applied to the module through the VME backplane. The SER COM (serial communication) LED is lighted solid green when the scanner is able to communicate with all of its slaves, flashes green when able to communicate with some of its slaves, and is out when unable to communicate with any of its slaves. The BPLN COM (backplane communication) LED lights green for half a second when a VMEbus access is made to the VMEbus I/O Scanner. The FLT (fault) LED lights red when the VMEbus I/O scanner is reset, performing a self test, or a fault has been detected.