The 'IOMOD10 - Carrier Board ' is a small PCB which the 'IOMOD10 - Sigma Calibration Module' plugs into. The carrier board allows an external (non Equinox) programming system to connect to the IOMOD10 module.
The external programming signals are routed from the 'carrier board' to the IOMOD 10 module. The 'Calibration oscillator' can then be enabled or disabled onto the SPI MOSI / MISO or UART TXD / RXD signals by use of an external 'Oscillator output ENABLE' signal