Inside the AS7010 Subscriber Terminal(ST) Meter

Overview

The AS7010 ST meter contains application designed for providing a handheld installation tool for assisting in the configuration and setup of wireless DSL subscriber terminals that operate in a point to multi-point configuration.

Explanation

A PIC16F877 microcontroller is the basis of the AS7010 ST meter wherein sufficient I/O pins are provided to interface to the keypad and drive an LCD while the MCU contains ADC and UART. The ADC functions like a voltmeter which allows the outdoor antenna to be aligned using the received signal strength. The information is passed to the main ST processor using a SLIP like protocol when the ST meter is attached to the ST maintenance port.  A bargraph is presented by the ST meter display refers to the received signal strength and compared to the constantly flickering display of a digital voltmeter, it is much easier to use. To periodically pass information to ST meter by encoding the information, the signal from the received signal strength pin is used.

The supplied power of the device can either come from two AA cells via step up regulator or the maintenance port of the Subscriber Terminal via step down regulator.