Communication method and apparatus

A system comprising a master device and at least one slave device, each of the devices comprising respective processing circuitry that includes a respective transceiver, the processing circuitry configured to operate the transceiver at a bit rate selected from a group comprising:

• a messaging bit rate and a data transfer bit rate, wherein the messaging bit rate is a fixed bit rate and the processing circuitry is configured to operate at the messaging bit rate when no data transfer is scheduled;
• wherein the processing circuitry of each device is configured to operate the respective transceiver at the messaging bit rate for communication of messages;
• wherein the processing circuitry of the master device is configured to, in response to being triggered for a data transfer, select at least one time slot in which to perform the data transfer, select a data transfer bit rate for the data transfer, and operate the transceiver to transmit to a said slave device an instruction to operate at the selected data transfer bit rate in the selected at least one time slot;
• operate at the selected data transfer bit rate in the selected at least one time slot to perform a data transfer;
• in response to being triggered for a further data transfer with a second slave device, a further at least one time slot being different to said at least one time slot:
• select the further at least one time slot in which to perform the further data transfer, select a further bit rate for the further data transfer, and operate the transceiver to transmit to the second slave device an instruction to operate at the further bit rate in the further at least one time slot;
• and operate at the further bit rate in the further at least one time slot to perform the further data transfer;
• and wherein the processing circuitry of the said slave device is configured to receive from the master device the instruction to operate the transceiver at the selected data transfer bit rate in the selected at least one time slot;
• and operate at the selected data transfer bit rate in the selected at least one time slot to perform the data transfer.

A method comprising:

• operating processing circuitry of a master device at a messaging bit rate for communication of messages, wherein the processing circuitry includes a transceiver, and the processing circuitry is configured to operate the transceiver at a bit rate selected from a group comprising:
• a messaging bit rate and a data transfer bit rate, wherein the messaging bit rate is a fixed bit rate and the processing circuitry is configured to operate at the messaging bit rate when no data transfer is scheduled;
• operating a transceiver of a slave device at the messaging bit rate for communication of messages, wherein the processing circuitry includes the transceiver and is configured to operate the transceiver at a bit rate selected from a group comprising:
• a messaging bit rate and a data transfer bit rate;
• in response to being triggered for a data transfer, selecting by the processing circuitry of the master device at least one time slot in which to perform the data transfer, selecting by the processing circuitry of the master device a data transfer bit rate for the data transfer, and operating the transceiver of the master device to transmit to a first slave device an instruction to operate at the selected data transfer bit rate in the selected at least one time slot;
• in response to being triggered for a further data transfer with a second slave device, a further at least one time slot being different to said at least one time slot:
• selecting the further at least one time slot in which to perform the further data transfer, selecting a further bit rate for the further data transfer, and operating the transceiver to transmit to the second slave device an instruction to operate at the further bit rate in the further at least one time slot, and operating at the further bit rate in the further at least one time slot to perform the further data transfer receiving, by the processing circuitry of the slave device the instruction;
• and operating the processing circuitry of the master device and the processing circuitry of the slave device at the selected data transfer bit rate in the selected at least one time slot to perform the data transfer.