Frequency hopping experiments on the NRF24

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Flynn
Posts: 43
Joined: 17 Feb 2018, 14:48

Re: Frequency hopping experiments on the NRF24

Post by Flynn »

Ummm..the plot thickens then... It is entirely possible (indeed, most likely after your comments on USBasp) that I used the usb com port to program the device for the first time, however it is now not greeted with the usual 'ding ding dong' when plugged in to windows, so no more programming.. at least that is what I thought... but it turns out, after your prompting, and after inspecting under the microscope, I had managed to short one side of the CH340 xtal to ground when soldering in a 100uF smt cap to the 3v3..
100uf.jpg
Now the serial ship is running again I can re-program the device.. :roll:

The nrf24l01+ is internally connected to the 3v3 line so I can't have damaged it with the usbasp.
It is stamped nRF24l01+ on the device.

It is supposed to be CE=D9 but now I can re flash it I am going to try t'other way around coz it ain't listening to the Tx at the mo.

Thanks for the offer....it may still come to it. First off I think I will wire up a vanilla Nano and a mini nrf24l01+ with the rx sketch with my variables to unequivocally prove the TX

More after this brief interlude!
You only ever need two tools....WD40 and duct tape.
If it doesn't move when it should use the WD40 and if it moves and it shouldn't use the tape.
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Phil_G
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Re: Frequency hopping experiments on the NRF24

Post by Phil_G »

According to https://github.com/nulllaborg/lgt-rf-nano BUT this has 9 & 10 swapped wrt the Keywish we've been using so far...

lgt8f328p_nrf24.jpg

I'd try the isplus test too = this will confirm its a plus and that the 328 is talking to it...
viewtopic.php?p=8890#p8890 you'll need to swap 9 & 10 tho if its different to the Keywish which is:
RF24 radio(10, 9); // RF-NANO and new builds, ce=10, csn=9

On the Tstars I had to physically buzz it out from the NRF legs to D7/8 as the docs were wrong!
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Flynn
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Joined: 17 Feb 2018, 14:48

Re: Frequency hopping experiments on the NRF24

Post by Flynn »

so...... the vanilla MiniPro and mini nrf24l01+ works, the LGT8F328P doesn't. The TX is working.

I tried adding the analogueReadResolution(10); to void setup() ..... no difference.

I can see the sck pulses, I can see CE goes +5V, I can see a 18kHz +5v square wave on CSN, I can see a clock pulse on SCK, if I touch MOSI with my scope probe the servos jitter (+5v but only a crappy 25mhz analogue scope) and I see 0v on MISO unless the servos are jittering then I see a noisy signal. No amount of stick stirring alters any of the signals........ the nrf24l01+ isn't seeing the incoming signal.


[about 2 hours later]

OK....mystery solved.... after reflowing and then replacing both the nrf24l01+ and the 16MHz crystal to no avail I have tracked the 'problem' down.....
yup..self inflicted! In order to get the veroboard servo connector pins installed I had to relieve the side of the RF-Nano board a touch, well... it turned out to be a touch too much as it removed the traces for CD, CSN and MISO between the NRF and the LGT8F328P.... dang those things are close to the edge of the board, I only needed 0.25mm or so......

Anyhow, I guess I am done with this, I have proved the TX conversion works and was thinking of asking Tobe if he has any PCB's spare to make a working radio set.
You only ever need two tools....WD40 and duct tape.
If it doesn't move when it should use the WD40 and if it moves and it shouldn't use the tape.
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Flynn
Posts: 43
Joined: 17 Feb 2018, 14:48

Re: Frequency hopping experiments on the NRF24

Post by Flynn »

Phil_G wrote: 17 Jun 2022, 12:21

On the Tstars I had to physically buzz it out from the NRF legs to D7/8 as the docs were wrong!
I think the docs here will be right as the examples that come with the IDE download also have RF24 radio(9, 10); and I have found the reason
why my board doesn't work, thanks anyway Phil. I have come to the conclusion you were right.... tobes Rx is the nicest solution!
You only ever need two tools....WD40 and duct tape.
If it doesn't move when it should use the WD40 and if it moves and it shouldn't use the tape.
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