81 Opto Input Modules

The Opto module is an easy to use optocoupler input module that increases the functionality of the 81 controller board. The module is designed so that it can accept a wide range of input voltages. It utilizes an ON Semiconductor optocoupler, part number H11L1M, which is a Schmitt trigger, inverting output chip. It plugs into either of the module ports on the 81 controller board. The Opto1 module uses the I2C bus to communicate with the microcontroller on the 81 board. It has DIP switches which enable address selection, as well as to engage or disengage pull-up resistors for the I2C bus. The module interfaces to the outside world via the 10-position pluggable terminal block.