Question about burning firmware to USB Dongle

[sdtjoe]

Hi,

I have a project based on the NUS (Nordic Uart Service) example.

I have bought a USB dongle MDBT50Q-RX manufactured by RAYTAC (https://www.raytac.com/product/ins.php?index_id=89), but I am not sure how to deploy my application to it. I would like to see if there is anyone here have experience on USB dongle which could give me some suggestion or guide.

At first, I just insert the USB dongle to the PC's USB. The PC can recognize the USB (Image 1) but nrf Connect for Desktop application (latest version, i.e. nRF Connect v3.3.1, Programmer v1.4.1) said the device does not support (Image 2), tested on both Mac OS and Windows.


(Image 1)


(Image 2)

Afterward I found these blog pages:
raytaccorp.blogspot.com/.../burn-your-firmware-onto-mdbt50q-rx-that.html
raytaccorp.blogspot.com/.../firmware-coding-dfu-onto-mdbt50q-rx.html

So I tried to wired with J-Link, I am able to burn my firmware either through SEGGER Embedded Studio > Target > Download ble_app_uart_c_pca10056_s140 or nrf Connect for Desktop. Just like other devices I previously used.
(Image 3, Sample of the dongle connected with J-Link RTT Viewer can view the NRF_LOG properly)


(Image 3)

However after burned and insert the dongle to PC, the COM port does not appear (Image 4).

(Image 4)

Am I missing something like incorrect setting?

Thank you very much.
Joe

[sdtjoe]

Hi

After many tries, I finally can receive the data through BLE and COM port detected by the PC.

So the next step I have to send out the buffer data.
As the dongle doesn't have UART, I think I have to send the data through the USB D+/D- pin to PC?

So my question is:
1. Shall I send the data through the app_usbd_cdc_acm_write(&m_app_cdc_acm, &data_buffer, data_len)?
2. How should I initialize the pin setting?
The pin for D+/D- are 35/34 repectively, so shall I set CDC_ACM_DATA_EPIN to 35 and CDC_ACM_DATA_EPOUT to 34?

APP_USBD_CDC_ACM_GLOBAL_DEF(m_app_cdc_acm,
cdc_acm_user_ev_handler,
CDC_ACM_COMM_INTERFACE,
CDC_ACM_DATA_INTERFACE,
CDC_ACM_COMM_EPIN,
CDC_ACM_DATA_EPIN,
CDC_ACM_DATA_EPOUT,
APP_USBD_CDC_COMM_PROTOCOL_AT_V250);

Thank you
Joe

[ovrebekk]

Hi Joe

Sorry for the slow response. 

It's good to hear that you got some progress on your end. 

sdtjoe said:

1. Shall I send the data through the app_usbd_cdc_acm_write(&m_app_cdc_acm, &data_buffer, data_len)?

 Yes. This function can be used to send data to the USB host from the nRF device. The CDC example that you're linking to can be used as a reference for this. 

sdtjoe said:

2. How should I initialize the pin setting?

 You don't have to select the pin when using USBD, since the USBD interface has dedicated pins on the chip that can  not be used for any other purpose. 

The CDC_ACM_DATA_EPIN and CDC_ACM_DATA_EPOUT defines sets the USB endpoints (EPIN means EndPoint IN), not the pins, and have to be values in the 0-5 range. I would recommend just using the same values as the CDC example, and not change these defines. 

Best regards
Torbjørn