DK-CH101 HelloChirp firmware doesn't work properly

i've encountered the same issue. both with sonic link software and with the hello chirp example. did you find any workaround?

I've been trying to get in contact with invensense technical support but the only suggestion i got was to flash the firmware with atmel tool instead of the tool provided in the soniclink.

Attached CH101 to STM32F0 Discovery board and ported SmartSonic_HelloChirp_v1_11_0 HAL to STM32. I2C communication seems to work according both osciloscope analysis and CH101 triggering interrupts in free running mode - so I'm assunming CH101 firmware is loaded and operational. However data returned look like random garbage (register dump added):

Hello Chirp! - Chirp SonicLib Example Application

    Compile time:  Feb  2 2021 00:04:45

    Version: 1.11.0    SonicLib version: 2.1.2
Initializing sensor(s)...

starting group...

OK
Sensor  Type       Freq          RTC Cal        Firmware

0       CH101    176703 Hz      2935@100ms      gpr_sr_open_gpr-101_v40a
Checking i2c devices on BUS after programming

  Found device on address 0x45
Configuring sensor(s)...

Sensor 0:       max_range=250mm         mode=FREERUN
Reading control registers

Register CH101_COMMON_REG_OPMODE: 2

Register CH101_COMMON_REG_TICK_INTERVAL: e1

Register CH101_COMMON_REG_PERIOD: 5

Register CH101_COMMON_REG_CAL_TRIG: 0

Register CH101_COMMON_REG_MAX_RANGE: 81

Register CH101_COMMON_REG_TIME_PLAN: 30

Register CH101_COMMON_REG_CAL_RESULT: 77

Register CH101_COMMON_REG_RX_HOLDOFF: a

Register CH101_COMMON_REG_STAT_RANGE: 0

Register CH101_COMMON_REG_STAT_COEFF: 6

Register CH101_COMMON_REG_READY: 2

Register CH101_COMMON_REG_TOF_SF: 2b

Register CH101_COMMON_REG_TOF: 6b

Register CH101_COMMON_REG_AMPLITUDE: 18

Register CH101_COMMON_REG_DATA: 0
Starting measurements

Port 0:  Range: 37.2 mm  Amp: 8164

Port 0:  Range: 84.6 mm  Amp: 38439

Port 0:  Range: 21.3 mm  Amp: 14529

Port 0:  Range: 21.3 mm  Amp: 15192

Port 0:  Range: 46.6 mm  Amp: 7031

Port 0:  Range: 46.6 mm  Amp: 4517

Port 0:  Range: 43.1 mm  Amp: 8125

Port 0:  Range: 44.6 mm  Amp: 4471

Port 0:  Range: 19.4 mm  Amp: 5297

Port 0:  Range: 45.1 mm  Amp: 4299

Port 0:  Range: 44.9 mm  Amp: 4299

Port 0:  Range: 84.8 mm  Amp: 38439

Port 0:  Range: 48.5 mm  Amp: 4517

Port 0:  Range: 38.8 mm  Amp: 4997

Port 0:  Range: 40.8 mm  Amp: 4155

Port 0:  Range: 21.3 mm  Amp: 6217

Port 0:  Range: 19.4 mm  Amp: 4861

Port 0:  Range: 45.1 mm  Amp: 4298

Port 0:  Range: 19.4 mm  Amp: 6734

Port 0:  Range: 19.4 mm  Amp: 11435

Port 0:  Range: 37.7 mm  Amp: 8723

Port 0:  Range: 21.3 mm  Amp: 6644

Port 0:  Range: 64.0 mm  Amp: 4398

Port 0:  Range: 21.3 mm  Amp: 5350

Port 0:  Range: 21.3 mm  Amp: 4938

Port 0:  Range: 44.0 mm  Amp: 8338

Port 0:  Range: 38.8 mm  Amp: 4587

Port 0:  Range: 67.9 mm  Amp: 4484

Port 0:  Range: 45.0 mm  Amp: 8124

Port 0:  Range: 21.3 mm  Amp: 38895

Port 0:  Range: 21.3 mm  Amp: 39097

Port 0:  Range: 46.6 mm  Amp: 5467

Port 0:  Range: 44.7 mm  Amp: 6700

Port 0:  Range: 19.4 mm  Amp: 6502

Port 0:  Range: 50.5 mm  Amp: 4692

Port 0:  Range: 40.8 mm  Amp: 4368

Port 0:  Range: 43.2 mm  Amp: 4299

Port 0:  Range: 56.3 mm  Amp: 5055

Port 0:  Range: 46.6 mm  Amp: 5467

Port 0:  Range: 46.6 mm  Amp: 5466

Port 0:  Range: 44.6 mm  Amp: 7031

Port 0:  Range: 44.6 mm  Amp: 7031

Port 0:  Range: 46.6 mm  Amp: 5467

Port 0:  Range: 38.8 mm  Amp: 4854

Port 0:  Range: 19.4 mm  Amp: 10339

Port 0:  Range: 42.7 mm  Amp: 6033

Port 0:  Range: 42.6 mm  Amp: 8265

Port 0:  Range: 84.6 mm  Amp: 38117

Port 0:  Range: 21.3 mm  Amp: 4858

Port 0:  Range: 84.4 mm  Amp: 38439

Port 0:  Range: 44.6 mm  Amp: 4517

Port 0:  Range: 43.2 mm  Amp: 4298

Port 0:  Range: 45.1 mm  Amp: 4298

Port 0:  Range: 84.7 mm  Amp: 38555

Port 0:  Range: 19.4 mm  Amp: 7022

Port 0:  Range: 19.4 mm  Amp: 5316

Port 0:  Range: 45.0 mm  Amp: 8124

Port 0:  Range: 19.4 mm  Amp: 9901

Port 0:  Range: 21.3 mm  Amp: 10248

Also other firwares present in SmartSonic_HelloChirp_v1_11_0 were tested, none of them privides relevant results.
For verification purposes DK-CH101 SmartSonic platform was bought and tested, with pretty much the same result. Any hints? Is it possible to use CH101 for any distance measuring at all?

Thank you.

Having the same issue with CH201, wrote to tech support, lets see if we can have some reply!

Hey michltriopscz,

Have you solved the problem？I would appreciate it if you could provide some information.

Best regards,
Victor

The answer is quite simple. It doesn't work. At least with a reasonable effort.

I soldered my own board with the CH101 and ported to a stm32f-series mcu. It delivered strange results. Due to the CH101-MOD (180 degree FOV) beeing in stock in the meantime I ordered to to verify my boards or the soldering process weren't faulty. I even made an adapter board with the TI SN74 bus driver to ensure I stick as close to the datasheet as possible.

The results are better but far from usable (so my custom horn is definitely part of the problem). In a static scenario (object remains in static for approx one sec) the range measurement jumps from 40 mm to 87 mm straight. If the object is moved the measurement jumps back to 40 mm and so on. I don't see the usecase of such a picky sensor.

By the way: porting was a nightmare. A simple datasheet with register description would have been a huge help.

I simply hope this is a firmware error. The chip itself would have such a wide variety of benefits.

Hello and sorry for late reply,

after some more trial and error, I was able to achieve quite good results. It seems firmware needs some time and target movement to detect obstacle to measure distance to. After that, it gives millimeter accuracy with some samples to be complete off range, which I'm simply discarding (target is always within specific range in my scenario). I was however unable measure the distance without moving the target first.

As a side note, providing library and not documentation is indeed a bit unfortunate.