HQ-ST Link System Manual

Rev. A00 HQ-ST System Manual Page 2 of 32
Primary Hardware Components of the HQ-ST System
The ST Plus and HQ Plus are the two essential hardware components in an HQ-ST Link. ST Plus devices, attached to
ECRs in stores, connect to their assigned HQ Plus device located at a head office.
ST Plus
The ST Plus is a device operates as a TCP/IP Raw Client, with the intention of providing a store-side serial-to-Ethernet
interface to an ECR or other similar device.
The ST Plus provides a serial port with the I/O characteristics and pin-out of a USR-type modem with a DB-25F
connector. To make a serial-to-serial connection from the HQ Plus's serial port to the ST Plus's serial port the
originating equipment connected to HQ Plus (typically a computer running ECR polling software) sends a dialing
string (ATDT5551234, for example) that causes a connection to be made to the serial port of the specific ST Plus (in this
example, known as 5551234) to which the receiving equipment (the ECR to be polled) is connected.
Figure 2: ST Plus
Figure 3: ST Plus: front connections