CS8C © Stäubli 2009 – D28070504A
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Chapter 5 - Integration
5.4. AS-I DIGITAL INPUTS/OUTPUTS (RS ARMS)
Note:
The AS-I function doesn't exist on ARMIO board of second generation.
Description
The RS arms support additional digital inputs and outputs on the fore arm, through the use of the AS-I bus that is
present on the CIO board (see chapter 5.3.1.7). This AS-I bus supports up to 13 AS-I slave modules of 4 digital
inputs and 4 digital outputs.
Configuration
AS-I Inputs/Outputs are configured in the /usr/configs/asi.cfx file. Each CS8C controller is supplied with an
example in which the configurations are commented out. To activate a configuration:
• Rename the /usr/configs/asiExample.cfx file in /usr/configs/asi.cfx.
• Remove the slave configurations that are not needed.
• For each remaining slave configuration, remove the Inputs/Outputs configurations that are not needed.
• If desired modify the default name of each AS-I Input/Output, and select its logical mode (inverted / notInverted).
• Restart the CS8C.
It is possible to define analog Inputs/Outputs based on the digital Inputs/Outputs of an AS-I module (see provided
asiExample.cfx file):
• The "channel" and "bitCount"' parameters define the first and the number of digital signals to use to build the
analog signal.
• The format of the analog signal is either "signed" or "unsigned".
• The "coefA" and "coefB" parameters define the linear transformation to apply:
• When writing on analog outputs, the linear transformation y = a.x + b is applied.
• When reading an analog input or output, the linear transformation x = (y-b) / a is applied.
Any configuration errors in the asi.cfx file are listed in the events logger on start-up. You can check the status of
the AS-I Inputs/Outputs in the Control Panel display.
WARNING:
• Only 4 slave modules are supported when they are powered by the CIO board. You need an
external power supply to support additional slave modules (up to 13).
• The AS-I bus of the CIO board supports the AS-I 1 specification: Analog Inputs/Outputs and
AB modules are not supported.
• Each slave module must have an address on the AS-I bus (a value between 1 and 13). This
address cannot be assigned with the CS8C controller. You need an external device to
configure it. Such AS-I configuration tools can be found by AS-I devices manufacturers.
• The slave modules present on the AS-I bus cannot be detected automatically by the CS8C
controller. You have to declare them to the controller (see Configuration hereafter).