Xycom XVME-202, Руководство пользователя

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XVME-202
Manual
December, 1986
Chapter 3
MODULE PROGRAMMING
3.1 INTRODUCTION
This chapter will briefly examine the addressing, and initialization procedures and
constraints required when programming the XVME-202 PAMUX Interface Adapter.
3.2 MODULE ADDRESSING
The XVME-202 is an odd byte only slave, and as such, the module will not respond
to even, single-byte accesses.
However, word accesses may be used, with the
understanding that only the odd byte of the word is used to exchange PAMUX data.
The PAMUX data bus is only 8-bits wide, while the PAMUX unit contains 32 points
of
I/O.
To be able to access all 32 points, the PAMUX is composed of 4
consecutive banks of 8 I/O channels (refer to Figure 3-l). Refer to the OPTO 22,
PAMUX
4 32 Channel Data Acquisition/Control System manual for information about
how to assign each PAMUX unit a base address. With 16 PAMUX units connected
to the XVME-202, there will be a block of 64 consecutive banks that could be
accessed.
3 - 1