User Manual

© Sealevel Systems, Inc.
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ACB-ULTRA.LPCI User Manual
Interface Selection
The ACB-ULTRA.LPCI supports a variety of electrical interfaces. Reference the
Control and Status Registers Defined section of this manual for this bit description.
There is line termination on RXD, RXC, and TXC in the following modes: RS-530,
RS-530A, RS-485T, and V.35.
Reset Circuit
Writing any value to base+3 will reset the Z16C32. Only one write is required. This
starts a reset sequence, which lasts about 320 ns. During the reset sequence base+3
bit D4 will read 0. When the reset is complete, base+3 bit D4 will read 1.
The Z16C32 should not be accessed until the reset sequence is complete.
TSET Clock Select
Port5 of Z16C32 is used to select TSET clock source.
 0 selects 16C32 TXC as source
 1 selects received TXC as source
Z16C32 Register Access
Pin Source
Port0 20 MHz clock
Port1 20 MHz clock
D/C (data/control) Address SA6
S/D (serial/DMA) Address SA7
DMA channel registers Base + 0-127
Serial controller base + 128-255