Motorola MVME167P, Инструкция по установке и эксплуатации

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I/O Interfaces
http://www.motorola.com/computer/literature 5-9
5
Parallel Port Interface
The PCCchip2 ASIC 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
∗
).
The PCCchip2 provides an auto-strobe feature similar to that of the
MVME147 PCC. In auto-strobe mode, after a write to the Printer Data
Register, the PCCchip2 automatically asserts the STROBE
∗
pin for a
selected time specified by the Printer Fast Strobe control bit. In manual
mode, the Printer Strobe control bit directly controls the state of the
STROBE
∗
pin.
Refer to the MVME1X7P Single Board Computers Programmer’s
Reference Guide for drawings of the printer port interface connections.
Ethernet Interface
The MVME167P uses the Intel 82596CA LAN coprocessor to implement
the optional Ethernet transceiver interface. The 82596CA accesses local
RAM using DMA operations to perform its normal functions. Because the
82596CA has small internal buffers and the VMEbus has an undefined
latency period, buffer overrun may occur if the DMA is programmed to
access the VMEbus. Therefore, the 82596CA should not be programmed
to access the VMEbus.
Every MVME167P that is built with an Ethernet interface is assigned an
Ethernet Station Address. The address is $0001AFxxxxxx where xxxxxx is
the unique 6-nibble number assigned to the board (i.e., every MVME167P
has a different value for xxxxxx).