Peritek VCD-V, User Manual

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Peritek
Theory of Operation 4-13
Table 4-1 VCT, VCU, VCD Common PLD Device Summary
Part Device
Number Type Description
VCDTU1 MACH230 Provides LRDY and BUSFLT to 34020. Supplies address
decoders for color maps, cursors, HSP, zoom register, PC
Keyboard, serial I/O, SCSI (VCT/VCU only), and DLUT
and pixel mux (VCD only). Has input jumpers for DRAM
size and 8 bit/pixel (VCD, VCU) or 32-bit/pixel (VCT)
VRAM. Supplies RAS lines for graphics and system
memory. Decodes LAD0-3 for page mode writes, refresh,
VRAM special functions (shift register load, writemask,
block fill, color register, ), and FPU select. Provides
modified SF line to VRAMs for correct special function
operation. Controls 74BCT16652 hidden writemask
register. Provides chip select and special address decoding
shift for autobooting PROMS.
VCDTU10 MACH230 Functions as a 32-bit registered bus transceiver with byte,
word, and long data swapping. All data passing between
VMEbus and 34020 side goes through this device.
VCDTU11 PALC22V10 Supplies CAS lines for display and system memory.
Decodes LAD0-3 to support VRAM block fill. Different
versions are required for VCD, VCT, and VCU.
VCDTU234 MACH435 A16, A24, A32 space VMEbus decoder, CSR bits 0-15,
LAR bits 0-15, A16/A24 DBR (line buffer base address)
bits 0-13, XAR (A32 space base address) bits 0-5, VEC
(interrupt vector) bits 0-7. Outputs drive 34020 host address
lines CMA 10-25. Data lines DA0-DA15 are I/O's for the
registers and output bits 0-7 of the interrupt vector.
Generates byte swap and bus control for VCDTU10.
Enables A24 and A32 VME block transfers.
VCDTU78 MACH230 VMEbus arbitrator and bus control. Address modifier
decoder. Generates 34020 autoboot/CRTCON, byte selects
and chip select. Control VMEbus 74BCT16652 bus
transceivers. Interrupt arbitrator. Transmits 34020 interrupt
to VMEbus. Buffers VMEbus address lines 2-9.