User`s guide

High-Speed Interrupts
Normally, the digital I/O system is checked once every V+ major cycle (every 16 ms). In
some cases, the delay or uncertainty resulting may be unacceptable. Digital signals 1001 -
1004 can be configured as high-speed interrupts. When a signal configured as a high-speed
interrupt transitions, its state is read at system interrupt level, resulting in a maximum delay
of 1 ms. The controller configuration utility CONFIG_C is used to configure high-speed
interrupts. See the INT.EVENT instruction in the V+ Language Reference Guide for more
information.
Soft Signals
Soft signals are used primarily as global flags. The soft signals are in the range 2001 - 2512
and can be used with SIG and SIGNAL. A typical use of soft signals is for intertask
communication. See "REACT and REACTI" and the REACT_ instructions in the V+ Language
Reference Guide.
Soft signals may be used to communicate between different V+ systems running on multiple
system processors.
1
Digital I/O and Third Party Boards
When V+ starts, default blocks of system memory are assigned to the digital I/O system. V+
expects to find the digital I/O image at these locations. If you are using a third party digital I/O
board, you must remap these memory locations to correspond to the actual memory location
of the digital I/O image on your board. See the description of DEF.DIO in the V+ Language
Reference Guide for details.
Digital I/O and DeviceNet
When V+ starts, default blocks of system memory are assigned to the DeviceNet system. V+
expects to find the DeviceNet image at these locations. For additional information, see
DeviceNet on page 237.
1
If your system is equipped with multiple system processors and the optional V+ Extensions
software, you can run different copies of V+ on each processor. Use the CONFIG_C utility to
set up multiple V+ systems.
Digital I/O
V+Language User's Guide, v17.0
Page 206