I'm trying to set up DTM environment with my DUT(Own device, using nRF51822) and a nRF51DK for Lower Tester, referencing the document, nAN34_v1.0, "Setting up production test using DTM".
I did setup as "Figure 2, Setup with PCB module with SMA connector as Lower Tester" of nAN34 document.
My problem is UART to nRF51DK is working correctly. But, UART to DUT is not working. Look at below scope capture. Red is RX line and Yello is TX.
First image is UART between nRF51DK and Computer.
Second image is UART between DUT and Computer.
I am sure UART of DUT is working correctly, tested with other firmware I developped. And, I'm using same DTM example(examples\dtm\direct_test_mode) with UART port number modified as DUT using.
I did erase all of flash of DUT and nRF51DK and flash blank build (examples\dtm\direct_test_mode\pca10028\blank). And, after reset, I trying "Direct Test Mode" of nRFgo Studio, choosing correct UART port and start test.
After then DUT's shows a pop-up window with message, "An error has occured in the serial connection. Please ensure that everything is connected correctly.". While nRF51DK is working correctly.
- Q1. Can I use blank build for DUT? Should I use Softdevice or boot loader?
- Q2. Is there any need to be done for DTM in H/W part?
- Q3, In what reason, UART does not respond as above image?
Best Regards. Jake
