Hello,
I have bought two VR Brain boards and I have several questions/problems. Can anyone help me with the following questions:
- I can only connect using ST-Link/V2 to the boards using SWD. When I try to connect using JTAG option the "STM32 ST-Link Utility" software gives me an error: "Internal command error" and do no connect to the VR Brain. I'm almost sure that the cable from the ST-Link/V2 (20 pins 0.1") to the connector in VRBrain is OK. I had followed the schematics and the link:
https://www.olimex.com/Products/ARM/JTAG/ARM-JTAG-20-10/resources/ARM-JTAG-20-10-schematic.pdf.
- What are the best ESCs to use with VRbrain? I have some BL-Ctrtl 2.0 from Mikrokopter that accepted I2C. The firmware of VRBrain is compatible?
Thank you very much,
Eduardo Pinto
Replies
Hi Eduardo ,
about Jtag normally we use SWD with ST-Link/v2 and it work fine . Some times i had some problem with OpenOcd and if we use the jtag for upload the program it fail upload ... so normally i use ST-Link outside OpenOcd and eclipse for upload firmware and openocd only for realtime debug.
About the compatibility of VRBRAIN with BL-Ctrl 2.0 i doing some test in early revision of Multipilot32 ... but on last revision of firmware the i2c support for Mikrokopter is deprecated ... could be possibile take old code and import in last revision of code ... is important to put a level shifter between the i2c of vrbrain and mk bl-control. The other option is put simon-K to Bl-control and use pwm to control MK Esc. If you want try better refresh rate you can try to use the range between 400 us and 1200 instead of 1000 - 2000 so you can improve the refresh rate from 490 hz to 700 hz
Best
Roberto
Hi Roberto,
Thank you very much for your help! I will try to make several tests with BL-CTRL 2.0 and when I have results I will post here!
About JTAG interface I continue not to understand why is not working, since all connections seem Ok and are direct from the connector U$1 to the micro. I think will ignore for now since the SWD option works well... but it was a pain to discrover that since the ST-link program starts with the option JATG by default...
I have now a clue but since I'm starting with this kind of microcontroller... Seems that "SWV: Serial Wire Viewer: A trace capability providing display of reads, writes, exceptions, PC Samples and printf" is active by default what implies that the pin "SWO - Serial Wire Output" shares the JTAG signal TDIO...
Could anyone confirm this??? As I told now that I have discover the SWD option works well is not really so important...
Once again thank you Roberto,
Eduardo