S2-LP (and its GUI) problems

[oleg239955_st]

Hi!

I have S2-LP connected to S2-LP GUI (only difference - it has no EEPROM on board, so I recompiled CLI firmware with EEPROM_NO define, and it has quartz running at 25MHz). I have to receive packets with 30-50kpbs datarate, but I made slower packets for testing.

1. If I try Running RSSI for OOK or ASK modulation, I get the following: https://prnt.sc/131we39. RSSI level on graph can raise, but cannot lower, it stale at maximum level S2-LP seen in session. If I press Stop then Start again - it starts from noise level again.
2. Second problem - I cannot get it working with OOK modulation. It breaks packets with 'silence' periods. This is picture from logic analyzer in 'RX data on GPIO without packet' mode: https://prnt.sc/131wk11. Upper channel is from transmitter side (real data on air), second channel is data that S2-LP shown on GPIO, and third channel - its clock.

I have not changed any registers except was changed by S2-LP GUI while freq/packet tuning with its input boxes.

Can you provide me with registers dump that can definitely work with OOK modulation on receive side?

Thank you in advance!

[AndyR1]

Hello,

Looks like you are using logic analyser from saleae, did u buy it on chinese website ?

[oleg239955_st]

I have no idea is it chinese or original, I got it as a gift from my friend. But it works, and I can see same signals on oscilloscope, so this is definitely not analyzer issue.

[oleg239955_st]

After some experiment I found that in some cases S2-LP can get packets and even parse them (at level of ~ -55dbm).

It depends on position of transmitter. With some registers values I got something like this: https://prnt.sc/1334xhx

As I understand, it senses noise like a bits, then packet starts, and it tunes AGC to receive itб but still bits missing inside packet. Then AGC relaxes in ~3ms, and starts to sense noise again till next packet.

I have no idea why this happens, I've tried to change MEAS_TIME, HOLD_TIME, OK_PEAK_DECAY, CS_MODE with no success - sometime it start to receive valid packets but slight moving a transmitter breaks receiving. Trying to change a data rate also leads to loosing bits.

Maybe someone have working registers dump for S2-LP in OOK mode?

[oleg239955_st]

Sometimes data received by S2-LP can 'invert' - and after this receiving almost finishes: https://prnt.sc/134116r

When received data on GPIO has idle high level - it receives something (not all bits, but I can guess some bits sequences), but after inverting (idle low) - it receives several bits only.. :(

Screenshot above was taken in 'RX data on GPIO without packet' mode with data rate = 64 kbps, manchester turned on. Same config with data rate = 32 kbps work better (but still depends on transmitter position relative to S2-LP, very narrow position when it can receive packets).

Maybe this is something relative to AGC tuning?

[AndyR1]

could you send me a pic of your analyser pls ? so i could tell u if its a counterfit or not, i've bought one of these counterfit (didn't know at this time), and i had issue when run sampling at 8MS/s, there is a power 20dB above noise level and it jammed my signal, so try another sampling rate maybe (i don't know about good saleae)