Board Level Hardware Description
1-8
MVME197IG/D1A1
1
Functional Description
The following sections contain a functional description of the major blocks on
the MVME197DP/SP single board computers.
Front Panel Switches and Indicators
There are two push-button switches and six LEDs on the front panel of the
MVME197. The switches are RESET and ABORT. The RESET switch (S3) will
reset all onboard devices and drive the SYSRESET* signal if the board
is
the
system controller. The RESET switch (S3) will reset all onboard devices except
the DCAM and ECDM if the board
is not
the system controller. The VMEchip2
generates the SYSRESET* signal. The BusSwitch combines the VMEchip2 local
reset, the power up reset, and the reset switch to generate a local board reset.
Refer to the
Reset Module
section in the
BusSwitch
chapter of the
MVME197LE,
MVME197DP, and MVME197SP Single Board Computers Programmer’s Reference
Guide
for more information.
The ABORT switch (S2) can generate an interrupt to CPU0 via the NMI* signal.
It is normally used to abort program execution and return to the debugger.
This capability is controlled via the ABORT register in the BusSwitch. Refer to
the
BusSwitch
chapter of the
MVME197LE, MVME197DP, and MVME197SP
Single Board Computers Programmer’s Reference Guide
for more information.
The six LEDs on the MVME197 front panel are: FAIL, SCON, RUN, LAN,
VME, and SCSI.
1.
The yellow FAIL LED (DS1) is lit when the BRDFAIL signal line is active.
2.
The green SCON LED (DS2) is lit when the VMEchip2 is the VMEbus
system controller.
3.
The green RUN LED (DS3) is lit when the MC88110 bus MC* pin is low.
4.
The green LAN LED (DS4) lights when the LAN chip is the local
peripheral bus master.
5.
The green VME LED (DS5) lights when the board is using the VMEbus or
when the board is accessed by the VMEbus.
6.
The green SCSI LED (DS6) lights when the SCSI chip is the local peripheral
bus master.
