read high speed analog sensor data and send data to pc

RE: read high speed analog sensor data and send data to pc

Jørgen Holmefjord — Wed, 30 Jan 2019 16:03:42 GMT

Your question does not make sense unless you can specify more what you are connecting to and what data you will transfer. We have different USB examples in the SDK, but there is no general example that can send any data to any device.

RE: read high speed analog sensor data and send data to pc

ratnakar1978 — Wed, 30 Jan 2019 14:39:04 GMT

Hi , Can you please suggest me how can I transfer data from Nordic chipset (nRF52480) dedicated USB port to host PC or external CPU USB Interface.

RE: read high speed analog sensor data and send data to pc

Jørgen Holmefjord — Fri, 28 Jul 2017 12:25:34 GMT

No, the MSC example should not need any driver, as this USB class should be supported by Windows already.

RE: read high speed analog sensor data and send data to pc

Tim — Fri, 28 Jul 2017 12:19:06 GMT

I did follow these steps to browse the driver manually but is it also necessary when doing the MSC example, to have this driver installed?

RE: read high speed analog sensor data and send data to pc

Jørgen Holmefjord — Fri, 28 Jul 2017 12:08:35 GMT

Yes, I had to browse the driver manually, as described in this answer.

RE: read high speed analog sensor data and send data to pc

Tim — Fri, 28 Jul 2017 11:59:12 GMT

Ok I removed the driver. When I reconnect the board, I get a message that for nRF52 USB CDC Demo, no driver was found. I'm using Windows 7. Until know I was working with the CDC ACM example, I will try implementing the MSC example.

RE: read high speed analog sensor data and send data to pc

Jørgen Holmefjord — Fri, 28 Jul 2017 10:29:45 GMT

The nordic_cdc_acm_example.inf driver should not be used with the MSC example, this is only for CDC ACM example. The device should enumerate as MSC device automatically. Which Windows version are you using? Have you tried removing the driver and reconnected the board?

RE: read high speed analog sensor data and send data to pc

Tim — Fri, 28 Jul 2017 09:55:29 GMT

The driver is not automatically installed when I connect the device to my computer. I added the nordic_cdc_acm_example.inf file manually in the driver settings but still the device doesn't show up as a removable disk so I can't retrieve any of the .txt files that should be created in this example.

RE: read high speed analog sensor data and send data to pc

Jørgen Holmefjord — Fri, 28 Jul 2017 07:21:19 GMT

Unfortunately, only up to 1 Mega baud is supported by the UART peripheral. Unfortunately, we do not have any file transfer examples. The closest we provide is the USB MSC Example. It is possible to use the FatFS driver in this example to store files on external QSPI flash, and then copy the files from the MSC device on your computer, but it will not work in an automated way. If you want to transfer files directly, you need to implement your own USB class. What is the issue with the driver? I tested it on Windows 7 yesterday and it worked fine. Also tested example on Windows 10, but there no driver is needed.

RE: read high speed analog sensor data and send data to pc

Tim — Thu, 27 Jul 2017 15:05:05 GMT

Thank you for your reply,

Increasing the baudrate partly fixed the problem with the overflow message. I can now reach up to 2.5k samples/sec. Is it possible to increase the baudrate beyond 1 Megabaud?

I'm indeed using nRF52840. I implemented the USB CDC ACM example but I would like to receive the data in a .txt file (also .xlsx file or .mat file would work). At this moment I can only view the data in the putty or termite terminal. There seems to be a problem with the Windows driver for the nRF52840 USB CDC ACM. Is there a fix for this?

Best regards

RE: read high speed analog sensor data and send data to pc

Jørgen Holmefjord — Thu, 27 Jul 2017 11:05:40 GMT

Hi Tim,

The SAADC peripheral support sampling rate up to 200 ksps, with aquisition time set to 3 us. With default settings from SAADC example from SDK (10 us aquisition time), you should be able to achieve 83.33 ksps sample rate.

The overflow message you are seeing is from the UART printing. You could try increasing the baudrate, for instance to 1 Megabaud.

If you are using the nRF52840, there is an USB CDC ACM example in the SDK, which emulates a virtual COM port over the USB interface. You should be able to modify this to transfer the ADC data to the computer. If you are using the nRF52832, there is no USB interface on this chip, but the Segger J-Link IF MCU on the nRF52 DK also provide Virtual COM port interface.

Best regards,

Jørgen