DRF1276DM

Revision 2.72

May. 2017

6/13

Wake timer

RF data rate

Sensitivity

64ms

5.47Kbs

-123Dbm

32ms

3.125Kbs

-136Dbm

16ms

1.758Kbs

-129Dbm

8ms

0.977Kbs

-132Dbm

4ms

0.537Kbs

-135Dbm

2ms

0.293Kbs

-138Dbm

Table 4:

Wake timer & RF data rate & Sensitivity

For node module, if the EN pin and the SET pin of it are set to logic low, it will work in full

performance so the central module doesn’t need to send long preamble. That’s why it is called

express communication. The disadvantage of this way is that the node module will consume

much higher current. Not matter in which way, the logic level of the SET pins of central

module and node module should be configured to the same in case the central module sends

the wrong length of preamble, which results in the loss of data. Please note that changing the

logic level of SET pin should be done after the EN pin is set to logic low.

Figure 5: Node Module in Express Communication

In star network mode the first two bytes of data package which central module sends to node

module should be the node ID of the targeted node module. When the node module detects the

effective wireless signal from central module, it will check the first two bytes of the data

package and compare it with its own. According to the value of node ID information in the

data package, the node module will have different process ways. Assuming central module

sends the data string: 0x00 0x01 0x02 0x03 0x04 0x05 (

the first two bytes must be the node

ID of the targeted module).



If the node ID of the node module is 0x00 0x00, when it receives the data package, it will transfer the

whole string [0x00 0x01 0x02 0x03 0x04 0x05] to the host (microcontroller or PC) and doesn’t filter the

ID information of the data package.



If the node ID of the node module is 0x00 0x01, when it receives the data package, it compares the first

two bytes of the data package and will know the data is for it. The module will filter the first two types

of ID information and transfer the real data string [0x02 0x03 0x04 0x05] to the host.