Jlink OB Clone? - Page 1
Forum section: electronics / general

author: skoehler
author_rank: Contributor
timestamp: December 16, 2019, 03:59:14 pm
content: Hi guys,has anyone purchased one of these JLink OB clones?https://www.aliexpress.com/item/4000249803796.htmlhttps://www.ebay.com/itm/J-OB-V2-JLINK-OB-JLINK-V8-V9-V9-3-STLINK-compatible-with-virtual-serial-port/352820813787What excites me about those clones is that they have SWO support and a virtual COM port! That reduces the number of adapters on my desk: The sellers claim that the device is not limited to ST controllers.JLink OB  is a Segger product designed for eval boards. It is the equivalent of the ST-Link on Nucleo Boards, in many ways. It seems the chinese may have cloned that.Another theory would be, that it is an ST Link V2-1 clone but flashed with a JLink firmware. See  for more information. But that doesn't seem to be equivalent to the JLink OB.The feature set is similar to the ST Link V2-1 on Nucleo boards. Those also offer a virtual COM port. But the chinese never cloned that. All clones that I can find come without a virtual COM port and seem to be based on the older V2 (without -1) design. Even the proper ST Link V2 (about 20€ at digikey) has no virtual COM port.Obviously, these clones have severe drawbacks: the target voltage is probably fixed at 3.3V, no debugging of 1.8V targets. Also, future firmware updates may brick them.https://www.segger.com/products/debug-probes/j-link/models/j-link-ob/https://www.segger.com/products/debug-probes/j-link/models/other-j-links/st-link-on-board/

author: thm_w
author_rank: Super Contributor
timestamp: December 16, 2019, 09:26:44 pm
content: Here is a smaller one with a picture of the PCB:https://www.aliexpress.com/item/32883585428.htmlLooks to be essentially the same as a stlink clone.There are some threads on here about adding the SWO and I believe com port wires to a stlink.That or you can use a bluepill + blackmagicprobe which has similar features.Or just try the one one you linked, less hassle and only a few $ more.

author: ebclr
author_rank: Super Contributor
timestamp: December 16, 2019, 09:57:27 pm
content: If your time is worth some money V10 is much fasterhttps://pt.aliexpress.com/item/4000047004785.html?spm=a2g0o.productlist.0.0.466e2975CctSOT&algo_pvid=edc383e3-8be8-4f47-8d0b-a3e8fceb5a4d&algo_expid=edc383e3-8be8-4f47-8d0b-a3e8fceb5a4d-0&btsid=b54d7c15-bb74-4766-93e4-497e6d8137fc&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_53

author: skoehler
author_rank: Contributor
timestamp: December 16, 2019, 10:50:26 pm
content: That link to V10 does not work.

author: thm_w
author_rank: Super Contributor
timestamp: December 16, 2019, 11:04:06 pm
content: Quote from: skoehler on December 16, 2019, 10:50:26 pmIt does, shorter link:https://www.aliexpress.com/item/4000047004785.html$46 though.

author: skoehler
author_rank: Contributor
timestamp: December 17, 2019, 12:55:41 am
content: Quote from: thm_w on December 16, 2019, 11:04:06 pmI get the message "A página que você procura não foi encontrada". Is AliExpress geo-blocking me!?

author: skoehler
author_rank: Contributor
timestamp: December 17, 2019, 01:18:03 am
content: Quote from: thm_w on December 16, 2019, 09:26:44 pmIt's the same microcontroller even: STM32F103.But the "smaller" one you linked has several disadvantages: no SWO, no virtual COM port, no RST pinQuote from: thm_w on December 16, 2019, 09:26:44 pmI found a blog from 2016 where somebody added the SWO to a similar unit:https://kiedontaa.blogspot.com/2016/11/ebay-j-link-ob-clone-swo-hacking.htmlBut the other disadvantages remain.Quote from: thm_w on December 16, 2019, 09:26:44 pmA while back, I turned a blue pill into an ST Link V2-1. But I have to say that I appreciate the convenience of a nice tiny device with a non-conductive case.

author: ebclr
author_rank: Super Contributor
timestamp: December 17, 2019, 03:26:28 am
content: This one It's original and cheaphttps://www.adafruit.com/product/3571

author: GromBeestje
author_rank: Frequent Contributor
timestamp: December 17, 2019, 06:54:21 am
content: These models I have no experience with. From the OB Series, I've got a purple one by CJMCU. Only does SWD. I haven't used it other then an initial test. Furthermore, I have two J-Link clones, a V8 (ILINKS) and a V9 (HLINK v9.43) . For both, I had to reflash them as the initial firmware was no good. The V8 seems to work perfectly fine, while the V9 seems to have some stability issues (resetting itself randomly).I have been aware there are newer variants of the V9 clones, and even V10 clones start to appear. I might order some to see what the Chinese are up to. Have they figured out the bootloader by now?One thing to be aware of: These J-Link clones appear to supply 3,3 volts on the V_target pin by default. This can be disabled by opening the device and replacing a jumper. Then it is the target voltage input just like the original JLink. CHECK THIS BEFORE CONNECTING BEFORE YOU BLOW THINGS UP.It seems some sellers are offering "simplified" versions, from the pictures, this appears to mean "without level shifting"-- disclaimer: educational purposes only --

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: December 17, 2019, 07:12:28 pm
content: I's still go with the EDU which is ~50€ without VAT:https://www.antratek.de/j-link-eduThe EDU is actually a PLUS hardware wise with just some licenses missing and a daily nag screen (but, well, there are ways around both issues).

author: GromBeestje
author_rank: Frequent Contributor
timestamp: December 17, 2019, 09:45:07 pm
content: Those nag screens only work on Windows. The Linux version lacks those.

author: skoehler
author_rank: Contributor
timestamp: December 18, 2019, 12:04:48 am
content: Quote from: 0xdeadbeef on December 17, 2019, 07:12:28 pmFor a professional project? of course! Unlike the clones, they offer JTAG, are compatible with different target voltages, and are probably much more reliable. They also have SWD+SWO support. But the virtual COM port is missing. That's a big missed opportunity. If a UART including level shifting was included, I would have a UART to connect to 1.8V targets, for example. I really miss that.

author: skoehler
author_rank: Contributor
timestamp: December 18, 2019, 01:51:54 am
content: Here's an unexpected find:https://www.aliexpress.com/item/32564971415.htmlDAPLink seems to be an open source design!

author: GromBeestje
author_rank: Frequent Contributor
timestamp: December 18, 2019, 07:39:02 am
content: Quote from: skoehler on December 18, 2019, 12:04:48 amThe J-Link EDU has VCOM (https://www.segger.com/products/debug-probes/j-link/models/j-link-edu/)The J-Link EDU Mini is the one that doesn't, and it lacks level shifting too, but the EDU has it all.Quote from: skoehler on December 18, 2019, 01:51:54 amThe DAPLink firmware is an open source project under an Apache license. (https://github.com/ARMmbed/DAPLink)The project is based on the Keil compiler, and requires a Keil license to build it. However, I don't think it would be too hard to port to gcc.At least, take the part that speaks the CMSIS-DAP protocol, and interface that to the USB code of your favourite microcontroller.Add some functions that control some GPIO pins, and that should be it. At least, that is my current analysis of the project,I still want to try if I can create my own debugger in the way I just proposed.

author: 0xdeadbeef
author_rank: Super Contributor
timestamp: December 18, 2019, 02:37:49 pm
content: RTT and Ozone alone are more than enough to buy a J-Link.

author: skoehler
author_rank: Contributor
timestamp: January 13, 2020, 12:59:30 am
content: I bought the JLink OB from ebay for about USD 3.90. It arrived and I fired it up. It survived a firmware update by the official SEGGER software and it found my blue pill attached to SWD. It's based on a STM32F072C8. I have yet to test the virtual COM port.

author: pablintino
author_rank: Contributor
timestamp: January 13, 2020, 11:38:22 pm
content: Quote from: 0xdeadbeef on December 17, 2019, 07:12:28 pmAnother vote for the EDU version if you are not going to make profit from it. Have been using it for 6 years as a hobbyst with multiple IDEs (Crossworks and Keil most of the times) and it has never failed or made weird things. Flashing is a bit faster than STlink v2.

author: voltsandjolts
author_rank: Unknown
timestamp: November 26, 2022, 04:26:10 pm
content: Waking a sleeping beauty here I know...I happened across aHackaday articleabout unbricking a J-Link V9, which was interesting enough but then I noticed one of the comments was from Rolf Segger himself.Nice, polite comment which leaves a positive impression of Segger as a company.Please do use official J-Link products for commercial work, they are fast and very reliable

author: eutectique
author_rank: Frequent Contributor
timestamp: November 26, 2022, 05:37:51 pm
content: Since that comment there were new developments, including closed hole in licensing of v10 and v11 probes:https://bi-zone.medium.com/vulnerabilities-in-j-link-licensing-system-or-why-researching-device-security-matters-b3ba1f9b469aEdit: fixed the link.

author: GromBeestje
author_rank: Frequent Contributor
timestamp: November 27, 2022, 09:24:29 am
content: Also an interesting read in the matterhttps://uglyduck.vajn.icu/ep/archive/2019/05/Unbricking_a_SEGGER_J_Link_v9_debug_probe.html

author: thm_w
author_rank: Super Contributor
timestamp: November 28, 2022, 10:54:32 pm
content: Quote from: GromBeestje on November 27, 2022, 09:24:29 amThats the hackaday link aboveQuote from: eutectique on November 26, 2022, 05:37:51 pmniceQuote