ENERGY SCAN

Not supported by the current SDK (2018-05, TWELITE NET 1.2.0 or later).

This is enabled by the module definition ToCoNet_REG_MOD_ENERGYSCAN. This module measures the specified channel level (including noise and signal).

A channel with a low channel level implies less communication and less noise, but the channel level at that moment does not guarantee channel availability. It is difficult to determine without multiple evaluations over a long period of time.

Only available on SimpleNet.

This function may cause a hang-up depending on the timing of its use. It is recommended to use this function when wireless packet communication is not used.

Definition

// define modules
#define ToCoNet_USE_MOD_ENERGYSCAN

// includes
#include "ToCoNet.h"
#include "ToCoNet_mod_prototype.h"

functions

ToCoNet_EnergyScan_bStart()

The energy scan is started. After completion the E_EVENT_TOCONET_ENERGY_SCAN_COMPLETE event is raised.

bool_t ToCoNet_EnergyScan_bStart(uint32 u32ChMask, uint8 u8Scale)

Argumtens

Type	Name	Remarks
uint32	u32ChMask	Channel mask to be measured (1UL<<<16 for ch16 only, 1UL<<16|1UL<<<17 for ch16,17)
uint8	u8PreScale	Measurement time. Approximately (2^u8PreScale)*16[ms]. The number of measurement channels is required. The measurement time should not exceed the internal timeout of about 1 second.

Returns

Type	Remark
boot_t	If TRUE the request was accepted, if FALSE the request was not accepted.

Event

case E_EVENT_TOCONET_ENERGY_SCAN_COMPLETE:
    _C {
        uint8 *pu8Result = (uint8*)u32arg;
    }

the value of pu8Result

byte offset	Remark
[0]	Number of channels measured [N].
[1]	Measured channel level for the youngest numbered channel
[2]	Next youngest channel number
... [N]	Data continues up to N

The level takes the value 0..255, with 0 being the weakest and 255 the strongest. The higher the value, the noisier the channel.

Sample code

// define module
#define ToCoNet_USE_MOD_ENERGYSCAN

// includes
#include "ToCoNet.h"
#include "ToCoNet_mod_prototype.h"

void inSomeFunc() {
	// start energy scan (scan 1ch only)
	ToCoNet_EnergyScan_bStart(1 << sAppData.u8channel, 2); 
	sAppData.bTxBusy = TRUE; // set internal busy flag.
}

void cbToCoNet_vNwkEvent(teEvent eEvent, uint32 u32arg) {
	int i;
	switch(eEvent) {
	case E_EVENT_TOCONET_ENERGY_SCAN_COMPLETE:
		_C {
			uint8 *pu8Result = (uint8*)u32arg;
			sAppData.u8ChEnergy = pu8Result[1];
			
			//save history...
			int i, max = 0;
			static uint8 u8Hist[8] = { 0 };
			static uint8 u8Idx = 0;
			u8Hist[(u8Idx++) & 0x7] = pu8Result[1];
			for (i = 0; i < 8; i++) {
				if (u8Hist[i] > max) max = u8Hist[i];
			}
			sAppData.u8ChEnergyMax = max;
			sAppData.bTxBusy = FALSE;
		}
		break;
	default:
		break;
	}
}