NCS: ESB how much are max ptx speed and what can i do to increase the speed

[spring.liu]

• My minimum requirement is 1568kbit/s .

I try the example that in    Nordic\ncs_v1.7.1\v1.7.1\nrf\samples\esb  ..

I increased the dynamic load to 252 ,and It can send about 700 packets in a second.

I  set  the  retransmission and autoack.

so, 252*700*8/1024=1378.kbit/s  ,Can not reach 2M .  Some devzone info says that 1.8mbps can be reached.

[Håkon Alseth]

Hi,

 

Some devzone info says that 1.8mbps can be reached.

In wireless applications, you will always have re-transmissions, meaning it is highly likely not possible with auto-acking enabled.

 

I increased the dynamic load to 252 ,and It can send about 700 packets in a second.

I  set  the  retransmission and autoack.

so, 252*700*8/1024=1378.kbit/s  ,Can not reach 2M

2 Mbit is the on-air datarate, and you will get a lower data throughput than this, as you have preamble, addressing and CRC in the on-air payload as well.

 

The default turn-around time for the radio is set, for compatibility reasons with nRF51 and nRF24L-series devices, to 130 us. "esb" library unfortunately does not have an API to change this at this time, so it must be set manually in your application.

You can change this by manually setting the MODECNF0 register, field "RU" to 1:

https://infocenter.nordicsemi.com/topic/ps_nrf52840/radio.html?cp=4_0_0_5_19_13_69#register.MODECNF0

 

If you set this register to '1' on both the PRX and PTX, each transmission will go down to 40 us ramp-up time and you will get a increased throughput.

 

Kind regards,

Håkon

[spring.liu]

You can change this by manually setting the MODECNF0 register, field "RU" to 1:

https://infocenter.nordicsemi.com/topic/ps_nrf52840/radio.html?cp=4_0_0_5_19_13_69#register.MODECNF0

it is the same with 5340  setting the MODECNF0 register, field "RU" to 1:

[Håkon Alseth]

Hi,

 

spring.liu said:

You can change this by manually setting the MODECNF0 register, field "RU" to 1:

https://infocenter.nordicsemi.com/topic/ps_nrf52840/radio.html?cp=4_0_0_5_19_13_69#register.MODECNF0

it is the same with 5340  setting the MODECNF0 register, field "RU" to 1:

Yes, this is similar in all nRF52- and nRF53 devices.

 

Kind regards,

Håkon

[spring.liu]

up to  1700kbit/s   I think that's the limit

[Håkon Alseth]

Hi,

 

spring.liu said:

up to  1700kbit/s   I think that's the limit

Yes, this is the very maximum, but please note that this is without any packet loss. As mentioned, you can get packet loss in a wireless connection.

 

Kind regards,

Håkon