Filter
Top Products
IQ80960RM/RN
Evaluation Board Manual 3-5
Hardware Reference
3.5.2 Interrupt and IDSEL Routing
3.6 Battery Backup
Battery backup is provided to save any information in SDRAM during a power failure. The
IQ80960RM/RN platform contains four AA NiCd batteries, a charging circuit and a regulator
circuit. The batteries installed in the IQ80960RM/RN platform are rated at 600 mA/Hr.
SDRAM technology provides a simple way of enabling data preservation though the self-refresh
command. When the processor receives an active Primary PCI reset it will issue the self-refresh
command and drive the SCKE signals low. Upon seeing this condition a PAL on the
IQ80960RM/RN platform will hold SCKE low before the processor loses power. The batteries will
maintain power to the SDRAM and the PAL to ensure self-refresh mode. When the PAL sees
PRST# returning to inactive state the PAL will release the hold on SCKE.
The battery circuit can be disabled by removing the batteries. LED CR4 indicates when the
SDRAMs have sufficient power. If the batteries remain in the evaluation platform when it is
depowered and/or removed from the chassis, the batteries will maintain the SDRAM for
approximately 30 hours. Once power is again applied, the batteries will be fully charged in about
four hours.
3.7 Loss of Fan Detect
The i960 RM/RN I/O processor can be cooled by an active heat sink mounted on top. The fan
provides a square wave output that is monitored by a comparator circuit on the IQ80960RM/RN
platform. The frequency of the fan output is approximately 9K RPM. If the frequency falls below
approximately 8K RPM the circuit will provide an interrupt to the processor. This is an evaluation
board feature intended as an example of system hardware monitoring, since the IQ80960RM/RN
platform does not ship with a heatsink.
Note: When using a passive heat sink, the processor never sees an interrupt from not having a fan.
Table 3-6. Secondary PCI Bus Interrupt and IDSEL Routing
Connector IDSEL INTA# INTB# INTC# INTD#
J11 SAD16 SINTA# SINTB# SINTC# SINTD#
J12 SAD17 SINTB# SINTC# SINTD# SINTA#
J13 SAD18 SINTC# SINTD# SINTA# SINTB#
J14 SAD19 SINTD# SINTA# SINTB# SINTC#