Technical data

Register Descriptions
MVME4100 Single Board Computer Programmer’s Reference (6806800H19B)
30
3.1.3 Status Indicator Register
The MVME4100 provides a Status Indicator Register that may be read by the system software
to determine the state of the on-board status indicator LEDs or written to by system software
to illuminate the corresponding on-board LEDs.
EEPROM_WP EEPROM Write Protect. This bit is to provide protection against inadvertent
writes to the on-board EEPROM devices. Clearing this bit will enable writes to
the EEPROM devices. Setting this bit write protects the devices. The devices are
write protected following a reset.
BRD_RST Board Reset. These bits are used to force a hard reset of the board. If a pattern is
written in bits 5-7 where bit 7 is set, bit 6 is cleared, and bit 5 is set (101), a hard
reset is generated. Any other pattern written in bits 5-7, does not generate a
hard reset. These bits are cleared automatically when the board reset has been
completed. These bits are always cleared during a read.
RSVD Reserved for future implementation.
Table 3-4 Status Indicator Register
REG Status Indicator Register - 0xF200 0002
BIT76543210
Field RSVD RSVD RSVD RSVD USR3 USR2 USR1
Y
USR1
R
OPERRRRRR/WR/WR/WR/W
RESET00000001
USR1R User LED 1 RED. This bit is used to control the USR1 bi-color LED located on the front panel.
A set condition illuminates the red segment of the front panel LED and a cleared condition
extinguishes the red segment of the front panel LED.
USR1Y User LED 1 Yellow. This bit is used to control the USR1 bi-color LED located on the front
panel. A set condition illuminates the yellow segment of the front panel LED and a cleared
condition extinguishes the yellow segment of the front panel LED.