Protocols: The default protocol

SPLatLink is our "native" protocol, and is what is used for downloading programs and interacting with the controller when debugging with SPLat/PC. SPLatLink can also be used for one on one communications between a SPLat controller and a PC.

Since writing this we have introduced ModBus support, which provides a richer feature set in a recognized standard protocol. We no longer support SPLatLink for use in customer applications.

SPLatLink is the default protocol. If you do nothing, SPLatLink is what you get. When a SPLat Controller first starts running your program, be it due to power being applied or a restart after a fatal error, the SPLatLink protocol will be in charge.

To invoke a different protocol you must switch protocols. This is done via a programming instruction. However, in the first 10 seconds after a reset (power up or restart after a fatal error) SPLatLink is unconditionally in charge. That means it is always possible to take control of a controller via SPLat/PC by clicking the "Connect" button in the Module window within 10 seconds of powering up the controller.