Real-Time Clock/Nvram/Timer Function - Motorola MVME2603-1121A Installation And Use Manual

The PIB controller provides the following functions:
Accesses to the configuration space for the PIB (PCI/ISA Bridge)
controller are performed by way of the CONADD and CONDAT
(Configuration Address and Data) registers in the Raven bridge
controller ASIC. The registers are located at offsets $CF8 and $CFC,
respectively, from the PCI I/O base address.

Real-Time Clock/NVRAM/Timer Function

The MVME2603/2604 employs an SGS-Thomson surface-mount
M48T59/T559 RAM and clock chip to provide 8KB of non-volatile
static RAM, a real-time clock, and a watchdog timer function. This
chip supplies a clock, oscillator, crystal, power failure detection,
memory write protection, 8KB of NVRAM, and a battery in a
package consisting of two parts:
PCI bus arbitration for:
Ð ISA (Industry Standard Architecture) bus DMA
Ð The PHB (PCI Host Bridge) MPU/local bus interface
function, implemented by the Raven ASIC
Ð All on-board PCI devices
Ð The PMC (PCI Mezzanine Card) slot
ISA (Industry Standard Architecture) bus arbitration for
DMA devices
ISA interrupt mapping for four PCI interrupts
Interrupt controller functionality to support 14 ISA interrupts
Edge/level control for ISA interrupts
Seven independently programmable DMA channels
One 16-bit timer
Three interval counters/timers
Functional Description
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