Echelon Series 6000 Chip databook - Manual (Page 118)

I/O Model
Applicable I/O
Pins
Total Pins
per Object Input/Output Value
Triac Output 2 IO0, IO1 + (one of
IO4 – IO7)
2 Delay of output pulse with
respect to input edge
Triggered-
Count Output
IO0, IO1 + (one of
IO4 – IO7)
2 Output pulse controlled by
counting input edges
Notes:
1. The Stretched Triac Output model is available for the following device types: FT
5000, Neuron 5000, FT 6000, and Neuron 6000.
2. Dual-edge triggering is not available for the following device types: Neuron 3150, FT
3150, or PL 3150.
Neuron Chips and Smart Transceivers have two 16-bit timer/counters on-chip. The input to
timer/counter 1, also called the multiplexed timer/counter, is selectable among pins IO4 –
IO7, through a programmable multiplexer and its output can be connected to pin IO0. The
input to timer/counter 2, also called the dedicated timer/counter, can be connected to pin IO4
and its output to pin IO1.
The timer/counters are implemented as a 16-bit load register writable by the CPU, a 16-bit
counter, and a 16-bit latch readable by the CPU. The load register and latch are accessed a
byte at a time. No I/O pins are dedicated to timer/counter functions. If, for example,
timer/counter 1 is used for input signals only, then IO0 is available for other input or output
functions. Timer/counter clock and enable inputs can be from external pins, or from scaled
clocks derived from the system clock; the clock rates of the two timer/counters are
independent of each other. External clock actions occur optionally on the rising edge, the
falling edge, or both rising and falling edges of the input.
For Series 6000 devices, many of the timer/counter I/O models can also trigger interrupt
tasks, which can provide minimum application latency for I/O events that are related to the
timer/counter models. See the Neuron C Programmer’s Guide for more information about
defining and using interrupts for Series 6000 devices.
Multiple timer/counter input objects can be declared on different pins within a single
application. By calling the io_select() function, the application can use the first
timer/counter to implement up to four different input objects. If a timer/counter is
configured to implement one of the output models, or is configured as a quadrature input
object, then it cannot be reassigned to another timer/counter object in the same application
program.
The following guidelines for declaring I/O object types apply to the I/O models shown in
Figure 44:
• 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
106 Input/Output Interfaces for the Series 6000