Questions about micro-esb

RE: Questions about micro-esb

djqtsg — Thu, 16 Jun 2016 07:06:49 GMT

can any one take a look at my question: devzone.nordicsemi.com/.../

RE: Questions about micro-esb

Håkon Alseth — Mon, 07 Mar 2016 07:17:36 GMT

The radio mode you want to use is set in the init of the uesb library (type uesb_config_t mode). If you set this to UESB_PROTOCOL_ESB_DPL, then you have two choices wrt. how you send an RF payload, noack or ACK.

To send using ACK, you have to set the "tx_payload.noack = 0" when pushing the payload to the TX FIFO to ensure that the library sets up the correct interrupts/shorts for the radio. If you send with tx_payload.noack = 1, then you will trigger "on_radio_disabled_esb_dpl_tx_noack()" when the payload has been send on-air.

If noack=0 when pushing the payload to the FIFO, then the PTX device will send the on-air payload and immediately start switching to RX mode to wait for an acknowledgement from the PRX device to ensure that the transfer was successful. If no acknowledgement is received, the PTX device will re-send based on your configuration.

Cheers, Håkon

RE: Questions about micro-esb

trk — Fri, 04 Mar 2016 21:44:50 GMT

@hakon

I was trying to understand how acknowledge mechanism works on micro esb. we are trying to work micro-esb as bi directional communication protocol.

This code snippet is transmit function in micro-esb.c in github. .

how to enable acknowledment? and can you explain on_radio_disabled_esb_dpl_tx_noack event and how auto tx mode works?

RE: Questions about micro-esb

Håkon Alseth — Fri, 11 Dec 2015 11:34:56 GMT

Fixed this on github. Thanks for pointing it out. Have a nice weekend:)

RE: Questions about micro-esb

Håkon Alseth — Fri, 11 Dec 2015 11:27:41 GMT

Ah, sorry for misunderstanding. This is a bug. This should be set to "UESB_CORE_MAX_PAYLOAD_LENGTH" to ensure that the max. size set in fw equals the size set in the radio registers.

RE: Questions about micro-esb

trk — Thu, 10 Dec 2015 20:42:47 GMT

Thanks for reply Hakon, I am just wondering that is there any particular connection interval time for ESB_DPL 2MPS configurations? I understand UESB_CORE_MAX_PAYLOAD_LENGTH. Anyways thanks for your explination but in the code base there is another variable called payload_length in general RF paramenters github.com/.../micro_esb.h How we need to select the payload_length parameters.

RE: Questions about micro-esb

Håkon Alseth — Tue, 08 Dec 2015 12:01:31 GMT

Hi,

Q1: µESB is based on the Enhanced Shockburst protocol that was first implemented on our nRF24L-series parts. You can find more information about this in the nRF24L01+ datasheet, or by checking out our blog: devzone.nordicsemi.com/.../

µESB can also differ from the "Enhanced Shockburst" implementation, as the nRF51-series can send up to 254 bytes in one RF payload, while the nRF24L-series could do 32 byte max. If backwards compatibility is needed, then you should set the define "UESB_CORE_MAX_PAYLOAD_LENGTH" to 32 byte max.

This variable only sets the maximum length, but it also allows you to send a value from 1 to "UESB_CORE_MAX_PAYLOAD_LENGTH" at any given RF-pipe, but only if you have initialized the library with protocol "UESB_PROTOCOL_ESB_DPL". This is the most common mode to use.

You can also set the library to use static length, so that it always sends the same amount of bytes in your payload, but this is a restriction that normally used only when having backwards compatibility with older nRF products.

Q2: The buffer size and packet drop does not have a correlation, other than you send more data through your link. It's the overall link integrity/signal strength that drives this. I would recommend testing how many packets that you get per second (use the RTC in 1 s interval for instance) and see if this is an accepted data throughput for your application.

Q3: This configuration sets the amount of buffers x size_of_max_payload. This means that you can upload 8 TX packets.

Cheers, Håkon