Documentation

Description

The -24 I/O interface extension uses the LVCMOS I/O lines of the Pulse* (see Note below) or IO3xx I/O to interface with two Resolver-to-Digital Converters (RDC). Each RDC provides a differential excitation output and sine and cosine inputs at the front connector to connect to a Resolver. Use the Resolver Measurement driver block to configure the interface.

The -24 extension converts some of the rear I/O lines from LVCMOS to RS422, RS485 and 3.3 V/5 V TTL and makes them accessible from the front of the enclosure. The extension has two possible digital I/O line configurations. The first configuration provides 8 differential I/O lines with RS422/485-compatible transceivers and 24 TTL I/O lines. The second configuration provides 40 TTL I/O lines but no RS422/485 I/O lines. The TTL I/O lines are distributed in groups of 8 lines. All 8 lines of a group must have the same direction and pull resistor configuration. The pull resistors of the TTL I/O port groups can be configured using the Setup block mask.

	Note
	* This information applies to MATLAB R2025a and later.

Pin Mapping -24

Warning

The resolver interface uses differential signals. The interface is designed to connect to the input and output windings of a resolver without ground reference. To avoid damaging the module, do not connect any of the resolver interface pins to ground. The output amplifier for the excitation signal works with a single positive supply voltage and adds a DC offset to both excitation outputs (positive and negative). If either of the excitation outputs (plus or minus) are connected to ground, the module will be damaged. The input circuit expects two pairs of fully differential and floating feedback signals from the resolver's secondary windings. A DC offset is applied to the input pins (plus and minus) to adjust the operating range of the input amplifier.