Echelon I/O Model Reference for Smart Transceivers and Neuron Chips User Manual
Page 18
8
Introduction
The following guidelines for declaring I/O object types apply to the I/O models
shown in Figure 1 on page 9:
• Up to 16 I/O objects can be declared.
• Timer/counter 1 can be multiplexed for up to four input objects.
• The neurowire, i2c, magcard, magcard_bitstream, magtrack1, and serial
I/O models are mutually exclusive. One or more of a single type of these
I/O models can be declared in one program.
• Because the parallel and muxbus I/O models require all I/O pins for some
Neuron Chips and Smart Transceivers, no other object types can be
declared when either of these objects is declared. You can declare the
IO11 pin as a bit input or output in addition to the parallel or muxbus
object for the following device types: PL 3120-E4, PL 3150, or PL 3170.
For Series 5000 devices, you can also declare the IO11 pin as a bit input
or output in addition to the parallel (master or slave A mode) or muxbus
object; the IO11 pin serves as an IRQ pin for the parallel (slave B mode)
object.
• Direct I/O object types (such as bit, nibble, byte) can be declared in any
combination; see
on page 17. Timer/counter,
serial, and neurowire I/O object declarations override the pin directions of
any overlaying direct I/O object types.
• The quadrature and dualslope input objects cannot be multiplexed with
other input objects on timer/counter 1. The edgelog input uses both
timer/counters and is exclusive of any other timer/counter objects.
• The bitshift I/O objects cannot be declared on the same I/O pins as
timer/counter objects. Direct I/O objects can be overlaid with bitshift I/O
objects. Two adjacent bitshift I/O objects cannot share any I/O pins.