Specifications

EPC-8A Hardware Reference
6
• Starts the IACK and bus grant daisy chains.
• Provides bus timeout error (BERR) function
The EPC-8A can be user-configured to provide standard VMEbus Slot-1 functionality.
The Slot-1 configuration option is enabled (default) by installing the Slot-1 shunt (jumper)
on the processor board (see Figure 2-1). Removing the jumper disables Slot-1
functionality. When the EPC-8A is configured as the Slot-1 controller, it performs all the
standard VMEbus system control functions.
Jumper JP2 (LOOP) is reserved for use by RadiSys and should not be installed.
The BIOS Jumper JP2 (-BIOS) enables the BIOS Flash memory for writing.
The Flash Jumper JP2 (-FLSH) enables the resident Flash memory for writing and must be
installed when using software such as the XFORMAT utility.
The Recovery Jumper JP2 (RCVR) must be installed only to recover a corrupted BIOS.
For example, if the power source was interrupted during a BIOS upgrade, and the corrupt
BIOS can only be reflashed by a Flash recovery floppy disk installed on EXM Slot 0.
Selecting the EPC-8A Slot Location
There are two main considerations in determining where the EPC-8A should be positioned
in the chassis.
• Per the VMEbus specification (Rule 3.3), the Slot-1 controller must be in Slot 1. All
other boards must be to the right of the Slot-1 controller.
Figure 2-1. Jumper Locations
Slot 1 controller jumper
Loop
Rcvr BBEN BIOS Flsh
JP2
Install the Boot Block
jumper (BBEN) only
when updating the flash
device’s Boot Block.