Parallel Port Interface - Motorola MVME167-32 User Manual

or synchronous port. It can operate at synchronous bit rates up to 64 k bits per second.
It uses RXD, CTS, DCD, TXD, RTS, and DTR. It also interfaces to the synchronous
clock signal lines. Refer to the MVME166/MVME167/MVME187 Single Board
Computers Programmer's Reference Guide for drawings of the serial port interface
connections.
All four serial ports use EIA-232-D drivers and receivers located on the main board,
and all the signal lines are routed to the I/O connector. The configuration headers are
located on the main board and the MVME712X transition board. An external I/O
transition board such as the MVME712X should be used to convert the I/O connector
pinout to industry-standard connectors.
N
The MVME167 board hardware ties the DTR signal from the
ote
CD2401 to the pin labeled RTS at connector P2. Likewise, RTS
from the CD2401 is tied to DTR on P2. Therefore, when
programming the CD2401, assert DTR when you want RTS,
and RTS when you want DTR.
The interface provided by the PCCchip2 allows the 16-bit CD2401 to appear at
contiguous addresses; however, accesses to the CD2401 must be 8 or 16 bits. 32-bit
accesses are not permitted. Refer to the CD2401 data sheet and to the PCCchip2 in the
MVME166/MVME167/MVME187 Single Board Computers Programmer's Reference
Guide for detailed programming information.
The CD2401 supports DMA operations to local memory. Because the CD2401 does
not support a retry operation necessary to break VMEbus lockup conditions, the
CD2401 DMA controllers should not be programmed to access the VMEbus. The
hardware does not restrict the CD2401 to onboard DRAM.

Parallel Port Interface

The PCCchip2 provides an 8-bit bidirectional parallel port. All eight bits of the port
must be either inputs or outputs (no individual selection). In addition to the 8 bits of
data, there are two control pins and five status pins. Each of the status pins can generate
an interrupt to the MPU in any of the following programmable conditions: high level,
low level, high-to-low transition, or low-to-high transition. This port may be used as a
Centronics-compatible parallel printer port or as a general parallel I/O port.
When used as a parallel printer port, the five status pins function as: Printer
Acknowledge (ACK), Printer Fault (FAULT*), Printer Busy (BSY), Printer Select
(SELECT), and Printer Paper Error (PE); while the control pins act as Printer Strobe
(STROBE*), and Input Prime (INP*).
MVME167/D3
MVME167 Functional Description
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