Function

Set RF channel

Purpose

Select a free RF channel for non-interfering communication

Syntax

void setRFchannel(uns8 channel)

Parameters

•     channel: see IQRF OS User’s guide, Appendix 2, Channel map. E.g., for the TR-77G series, only channels 45 to 67 are allowed.

•     Default:     868 MHz band:      52

                     916 MHz band:    104

                     433 MHz band:        8

The default channel can be changed by TR Configuration in IQRF IDE.

Return value

  –

Output values

Available read only in the RFchannel register

Preconditions

•     To avoid interferences between adjacent RF channels, the selection should respect the following rules (typical, in most cases):

•     STD mode: There are no interferences even between very adjacent channels.

•     LP or XLP modes: 10 channel spacing is required in the worst case.

Channels not interfering with each other can be used in two overlapping IQRF networks transmitting at the same time. Interferences between two IQRF transceivers in LP or XLP modes significantly decrease with the distance between those transceivers.

Examples of interference between two IQRF transceivers:

•     Channels 50 and 51 typically do not interfere in STD mode at any distance.

•     Channels 50 and 60 or higher typically do not interfere in all modes at any distance.

•     Channels 50 and 51 may typically interfere in LP or XLP at the 1 m distance.

•     Channels 50 and 51 typically do not interfere in LP or XLP at the 20 m distance.

But in all cases, it is recommended to observe spacing as high as possible.

Remarks

Channel 0 is reserved for DPA service purposes. It is not recommended to use it for regular communication.

Side effects

  –

See also

  –

Example

setRFchannel(10);          // 864.15 MHz channel selected (for 868 MHz band)

                           // 903.25 MHz channel selected (for 916 MHz band)

                           // 434.10 MHz channel selected (for 433 MHz band)