user manual

3 Functional Description

PrPMC800/800ET Processor PMC Module Installation and Use (PrPMC800A/IH5)

PrPMC800/800ET Power Supplies

The PrPMC800/800ET module requires only a +3.3V input voltage. The processor core voltage

and the Harrier core voltage are generated on the module from the +3.3V input using the

LTC1702 dual synchronous switching regulator. In addition to the Harrier core voltage, the

+2.5V supply provides the processor, Harrier, and L2 cache I/O voltages.

Module Reset Logic

A block diagram of the PrPMC800/800ET module reset logic appears in Figure 3-2 on page 24.

There are five standard sources of reset on the PrPMC800/800ET. They are:

1. Power-Up reset

2. PMC PCI RST#

3. Watchdog Timer reset via the Harrier Watchdog 1 Timer output

4. Software generated module reset from Harrier RSTOUT control bit

5. Debug RESET_L signal from debug header

The following table describes the function of each reset source. A module reset includes the

processor, Harrier and Ethernet. The RESETOUT_L pin must be tied into the baseboard reset

logic, which drives PCIRST# in order to produce module reset.

Table 3-4. Reset Source Functions

Reset Source Type Module Reset PrPMC RESETOUT_L

Active

Power-Up Reset x x

PMC PCI RST# x

WDT1 Timer Output x

SW Reset x

Debug Reset x