HARDWARE
CPCI-824 User’s Manual
2-9
Revision 1.0, January 2006
2.8.5
Power Supply Monitoring
Two circuits are provided for monitoring the health of power supplies. Additional inputs to the
CompactPCI connector define pins for degraded, failed and detected power supplies. The definitions
for the CompactPCI connector J2 is provided in Appendix B. A failed or degraded power supply, as
long as it is detected, will cause an interrupt to the processor. Additionally, the state of the power
supply as defined by POWERGOOD, i.e. the power supply is neither degraded or failed, is displayed in
a green LED. Figure 2-4 shows the bit definition for the power supply status register.
Figure 2-4. Power Supply Status Register, E800 0000H
2.9
FAN MONITORING
Two circuits are provided for monitoring of the two fan frequency inputs. As in the case of the power
supply monitoring signals, additional inputs to J2 have been defined for the two fan inputs. Refer to
Appendix B for their pin locations. The fan monitoring circuits will provide an interrupt to the
processor if the frequency of the fan output falls below approximately 8K RPM. Green LEDs are
provided for fan interrupt status. If a fan frequency input causes an interrupt, the corresponding LED is
turned off.
2.10
I
2
C BUS
The CPCI-824 has five components attached to the Inter-Integrated Circuit (I
2
C) bus interface #0 of the
PPC440GP processor: the DDR SDRAM EEPROM, the two temperature sensors, the reset configu-
ration Serial EEPROM, and the DDR SDRAM phase lock loop clock driver. The I
2
C addresses of the
devices are shown in Table 2-7.
PS0 Failed
Degraded
PS1 Detected
PS0 Detected
PS1 Failed
0
1
3
2
4
5
6
7
