Embedded PC/RTOS Features 45
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3 • Embedded PC/RTOS Features
GE’s V7768/V7769 feature additional capabilities beyond those of a typical
desktop computer system. The units provide four software-controlled, general-
purpose timers along with a programmable Watchdog Timer for synchronizing
and controlling multiple events in embedded applications. The V7768 provides a
bootable CompactFlash Disk system and 32 KByte of non-volatile RAM. Also, the
V7768/V7769 support an embedded intelligent VME bridge to allow compatibility
with the most demanding VME applications. These features make the unit ideal
for embedded applications, particularly where standard hard drives and floppy
disk drives cannot be used.
3.1 VME Bridge
3.1.1 Features
• Complete six-line Address Modifier (AM-Code) programmability
• VME data interface with separate hardware byte/word swapping for master
and slave accesses
• Support for VME64 multiplexed MBLT 64-bit VME block transfers
• User-configured interrupter
• User-configured interrupt handler
• System Controller mode with programmable VME arbiter
(PRI, SGL and RRS modes are supported)
• VME BERR bus error timer (software programmable)
• Slave access from the VME to local RAM and mailbox registers
• Full-featured programmable VME requester
(ROR, RWD and BCAP modes are supported)
• System Controller auto detection
• Complete VME master access through five separate Protected-mode
memory windows
The V7768/V7769 support High Throughput DMA transfers of bytes, words and
longwords in both Master and Slave configurations.
If Endian conversion is not needed, GE offers a special “Bypass” mode that can be
used to further enhance throughput (not available for byte transfers).
The V7768/V7769 VME interface is provided by the PCI-to-VME bridge built
around the Tundra Semiconductor Corporation Universe IID VME interface chip.
The Universe IID provides a reliable high-performance 64-bit VME-to-PCI
interface in one design. The functions and programming of the Universe-based
VME interface are addressed in detail in a companion manual titled:
GE’s Tundra
Universe II Based VME Interface Product Manual
(500-000211-000)
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