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STP2002QFP
Fast Ethernet, Parallel Port, SCSI (FEPS) - STP2002QFP
Sun Microsystems,
4.4 Differences from STP2000 (MACIO) Parallel Port• PP_INIT and PP_AFXN have extra functions: high and low address
latch clocks
• EPROM address is given by parallel port data bus
• DIR bit in the TCR register must be set during memory clear operation
4.5 Test SupportThe TST_CSR provides a way for the user to test the DMA engine. The test
consists of moving one block data of the size of a read burst from the host
memory into the FIFO. The user then instructs the engine to drain data back
to the host memory at an address which is programmable.
The maximum size of a read burst is 32 bytes. Since the starting address of
the FIFO register cannot be programmed, the user has no control over which
FIFO registers should be tested. And since the maximum size of the burst is
limited to 32 bytes, the entire FIFO (64 bytes) cannot be tested.