5
BVME4000/6000
Copyright
1993,1995,1998,2001 BVM Ltd.
3.2 Processor
The BVME4000 is based on the MC68040 32-bit processor from Motorola running at 25 or 33MHz.
This virtual memory processor provides a MC68030 compatible integer processor running
concurrently with an IEEE754 compatible floating-point unit (FPU). In addition two fully independent
data and instruction demand page memory management units (MMU's) and two independent 4Kbyte
caches provide efficient bus interface with a high degree of instruction execution parallelism.
The BVME6000 is similar to the BVME4000, but is based on the MC68060 32-bit processor from
Motorola running at 50MHz with a 25MHz bus. The MC68060 provides a MC68040 compatible integer
processor running concurrently with a MC68040 IEEE754 compatible floating-point unit (FPU). In
addition two fully independent data and instruction MC68040 compatible demand page memory
management units (MMU's) and two independent 8Kbyte caches.
The BVME4000 and BVME6000 are also available in lower cost versions with the
MC68LC040/68LC060, which provide the same functionality as the MC68040/68060, but without the
FPU, and with the MC68EC040/68EC060 which provide the same functionality, but without the MMU
or FPU. The MC68LC060/68EC060 can run at 50 or 66MHz with a 25 or 33MHz bus respectively.
3.3 Memory
The BVME4000/6000 may be fitted with a large variety of 32-bit wide, burst fill memory devices. The
BVME4000/6000 uses the BVM memory module interface which provides a full 32-bit MC68040/68060
bus, and supports 2/1/1/1 (no wait state) accesses to a variety of standard BVM memory modules,
allowing use of memory modules which currently include:
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8 to 48Mbytes DRAM (5/3/3/3 access at 33MHz bus clock).
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16 to 512Mbytes DRAM (4/1/1/1 read, 3/2/2/2 write at 25 & 33MHz bus clock).
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16Mbytes DRAM plus 8Mbyte FLASH EPROM (4/2/2/2 DRAM, 5/2/2/2 FLASH access).
This memory can be dual ported allowing concurrent accesses by both the processor and other
VMEbus masters. These accesses may be 'snooped' by the processor to maintain cache coherency.
This, together with the onboard 'location monitor' allows full multiprocessor communication with other
CPU (and DMA) VMEbus cards.
The BVME4000/6000 also provides 2Mbytes (512Kbytes to special order) of battery-backed 32-bit
wide Static RAM, providing a 5 CPU clock cycle access at 25MHz or 33MHz bus clock. This SRAM
may be used for non-volatile storage applications, or as main system memory in applications where a
memory module is not fitted. The SRAM can also be dual ported to the VMEbus.
A pair of 32-pin JEDEC pinout sockets provide up to 2Mbytes of 16-bit wide EPROM providing a 10
CPU clock cycle access at 25MHz or 33MHz bus clock. These sockets can support 512K, 1M, 2M, 4M
and 8Mbit EPROM devices, and up to 4Mbit 5V FLASH devices.
3.4
Real Time Clock
The BVME4000/6000 provides a battery backed Real Time Clock using the DP8570 device. This
device is battery backed, and maintains date and time data. The DP8570 can also generate an
interrupt from it's periodic timer from 1mS to 1 second, or from two other independent 16-bit timers on
chip. The timers offer a resolution of up to 500nS, and can be used in one-shot or periodic interrupt
mode. A small amount of non-volatile storage is also provided for system configuration purposes. The
DP8570 is battery backed using a lithium battery giving typically 10 years of non-volatile operation.
