The PCL-724 offers 24 programmable digital I/O lines on a half-size PC add-on card. Each port emulates the operation of an 8255 Programmable Peripheral Interface (PPI) chip in mode 0 but provides a higher driving capacity than the 8255.
The PCL-724's 24 bits of DI/O are divided into three 8-bit ports (A, B and C). You can configure each of these ports individually by software for either input or output. The card can directly control SSR carrier modules through a 50-pin Opto-22 compatible connector.
The PCL-724 is a low-cost alternative to the PCL-722 for applications that require up to 24 I/O channels. Like the PCL-722 it provides a readback feature which lets you monitor the status of the output by reading back the output port directly.