The Talking Compass Circuit

A talking compass consists of a Hall-effect direction sensor (MODI) and an ISD1016 analog audio storage device. It can store eight two-second announcements for each of the eight primary compass directions. The Talking Compass includes a digital compass (MODI), an ISD1016 analog storage device (U2), a 74S188 preprogrammed PROM (U3), and several additional components.

The talking compass system operates by utilizing the Hall-effect direction sensor, which detects the Earth's magnetic field to determine the compass heading. The MODI sensor outputs digital signals corresponding to the direction the compass is facing. This information is processed and used to trigger the appropriate audio announcement stored in the ISD1016 device.

The ISD1016 is an analog storage device capable of recording and playing back audio. It allows for the programming of up to eight distinct audio messages, each lasting two seconds, which correspond to the eight primary compass directions: North, Northeast, East, Southeast, South, Southwest, West, and Northwest. The audio messages can be recorded and programmed by the user, enabling customization of the compass announcements.

The 74S188 preprogrammed PROM serves as a memory component that stores the audio message addresses and controls the playback sequence. This PROM is integral to the operation of the talking compass, as it ensures that the correct audio message is played back in response to the directional input from the MODI sensor.

Additional components in the circuit may include resistors, capacitors, and power supply elements that support the operation of the Hall-effect sensor, audio storage device, and PROM. The entire assembly is typically housed in a compact enclosure, allowing for portability and ease of use in various outdoor navigation applications. This talking compass is particularly beneficial for visually impaired users, providing auditory direction cues to enhance navigation. A talking compass is made up using a Hall-effect direction sensor (MODI) and an ISD1016 analog audio storage device. It is possible to program eight two-second announcements, for each of the eight main compass directions.

The Talking Compass is comprised of a digital compass (MODI), and ISD1016 analog storage device (U2), a 74S188 preprogrammed PROM (U3), and a handful of additional components. 🔗 External reference