Hardware manual

3 Programmers Reference EUROCOM-17-5xx
78 Hardware Manual
3.15 Reset
During power-up or after actuation of the reset switch (S4), /RESET is
held low for approximately 1s. If the system controller switch (S3) is in
the 'SC' position, the VMEbus is also reset because the VIC is configured
as the VMEbus system controller. Otherwise SYSRESET from the
VMEbus is an input.
The reset switch or power-up reset affect all modules and chips on the
EUROCOM-17-5xx board, and also the VMEbus SYSRESET line if
switch S3 is in the 'SC' position. The LED included in the reset switching
socket shows the status of the RESET line. RESET inactive means LED is
illuminated.
If the reset is generated by the watchdog, the left decimal point of the hex
display (watchdog indicator) is active and stays illuminated until it is reset
by a voltage drop < 4.75V, power-up, reset switch, SYSRESET, or VIC
remote control reset. The state of the watchdog indicator can be read by
port PA7 of the system CIO.
A remote reset via VIC’s reset register or a VMEbus SYSRESET behaves
the same way as a power-up reset, except that the VMEbus configuration
(VIC register and master/slave address) is not changed.
Table46: Reset Conditions
Reset Source Effected Device
Voltage Drop < 4.75V
or Power-up
or Reset Switch S3
CPUs, CL-CD2401, CIOs, Keyboard Controller,
SCSI Controller,
ILACC,
VMEbus SYSRESET (if system controller),
Watchdog Indicator,
VMEbus Slave Decoder
VIC Remote Control Reset
or SYSRESET
CPUs, CL-CD2401, CIOs,
SCSI Controller,
ILACC,
Watchdog Indicator
Watchdog Reset CPUs, CL-CD2401, CIOs, Keyboard Controller,
SCSI Controller,
ILACC,
Primary CPU SCSI Controller,
ILACC