UMAC-CPCI Turbo CPU Board Hardware Reference Manual
Board Configuration 5

HARDWARE SETUP

Clock-Source Jumpers

In order to operate properly, the Turbo CPU board must receive servo and phase clock signals from a
source external to the board. These clock signals can be brought into the board from one of three possible
ports: the stack connector, the UBUS backplane connector, or the front-side main serial-port connector.
Jumpers E1A and E1B must be configured properly for the clock source used.
(Note: If the UMAC-CPCI Turbo CPU board cannot find the clock signal from the source specified by
these jumpers, it will generate its own 2.26kHz servo clock and its own 9.04kHz phase clock so it will
stay in operation.)
To receive the clock signals over the Compact-UBUS backplane, usually from an ACC-24C2x axis-
interface board, E1A must connect pins 1 and 2, and E1B must connect pins 2 and 3. This configuration
is typical for an UMAC-CPCI system. The clock signals are output on the main serial port.
To receive the clock signals through the stack connectors, usually from the MACRO IC on the CPCI
“bridge” board, E1A must connect pins 1 and 2, and the E1B jumper must be removed. The clock signals
are output on the main serial port.
To receive the clock signals through the main serial port, usually from another UMAC system or a
reference signal generator, E1A must connect pins 2 and 3, and E1B must connect pins 1 and 2. This
configuration is rarely used, but permits complete synchronization to the system that is generating the
clock signals.

Watchdog Timer Jumper

Jumper E19 should be OFF for normal operation, leaving the watchdog timer circuit active and prepared
to shut down the card in case of a severe problem. Putting jumper E19 ON disables the watchdog timer
circuit. This should only be used for test purposes, in trying to track down the source of watchdog timer
trips. Normal operation of a system with this jumper ON should never be attempted, as an important
safety feature is disabled.

Operation Mode Jumpers

Jumpers E20, E21, and E22 control the operational mode of the UMAC-CPCI Turbo CPU. For normal
operation, E20 must be OFF, E21 must be ON, and E22 must be ON. Other settings of these jumpers are
for factory use only.

Firmware Reload Jumper

Jumper E23 should be OFF for normal operation. If you want to load new firmware into the flash-
memory IC on the CPU, E23 should be ON when the card is powered up. This puts the card in “bootstrap
mode”, ready to accept new firmware. If you then try to establish communications to the card with the
Executive program, either over the main serial port or the optional USB or Ethernet ports, the Executive
program will automatically recognize that the card is in bootstrap mode, and prompt you for the firmware
file to download.

Re-Initialization Jumper

Jumper E3 should be OFF for normal operation, where the last saved I-variable values are loaded from
flash memory into active memory at power-up/reset. If E3 is ON during power-up/reset, the factory
default I-variable values are instead loaded into active memory at power-up/reset. The last saved values
are not lost when this happens. This jumper is typically only used when the system’s set up has a
problem severe enough that communications does not work – otherwise, a $$$*** command can be
used for re-initialization.