1.2 Functional Description

For serial transmissions from the Microchip communication firmware stacks 'uplink', the embedded USI provides a function that packs and sends each primitive through the serial link to the external application. Upon reception, the USI Host unpacks the message, extracts received parameters, and calls a user configured callback function.

For serial transmission to the Microchip communication firmware stacks 'downlink', the USI Host provides the external application with a set of functions identical to the ones described in the Microchip communication stacks. When any of these functions are invoked, the primitive is packed and sent through the serial link to the remote device. Upon reception, the Embedded USI unpacks it, extracts received parameters, and transfers the control to the corresponding stack module.