Difference between ST-LINK/V2-1 and ST-LINK/V2

[richard239955_stm1]

Posted on April 14, 2016 at 07:51

What is the difference between, ST-LINK/V2-1 and ST-LINK/V2?

Which one is on the STM32F4 Discovery? Which firmware am I supposed to use to update the ST-LINK ????? on the STM32F4 Discovery?

[waclawek.jan]

Posted on April 14, 2016 at 09:53

> What is the difference between, ST-LINK/V2-1 and ST-LINK/V2?

V2-1 when connected to USB host, provides a mass storage (a virtual ''disk''), where you can copy a binary and it in turns programs it into the target. Additionally it provides also a virtual serial port. Both these features were added because of mbed compatibility.

> Which one is on the STM32F4 Discovery?

That's a tricky question. ST is very inconsistent in marking the DISCOVERY boards, so they tend to have several names. Adding to the confusion, there are several DISCOVERY boards based on different STM32F4xx models, and users here tend to call any of them ''STM32F4 DISCOVERY''. Furthermore, if you are talking specifically about the ''Discovery kit with STM32F407VG MCU'', http://www2.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-eval-tools/stm32-mcu-eval-tools/stm32-mcu-discovery-kits/stm32f4discovery.html , there are two of them - the older, tagged ''STM32F4DISCOVERY'', which has STLINK/V2, and a newer, tagged ''STM32F407G-DISC1'', which has - get ready for more confusion - what they call ''ST-LINK/V2-A''. ST-LINK/V2-A is supposedly a variant of ST-LINK/V2-1, providing the mbed compatibility (albeit on the STM32F407G-DISC1 the virtual serial port is barely usable, as ST forgot to connect Rx/Tx tracks between the STLINK and target processor thus using it requires to patch the board with wires), but I have no idea why is it marked differently, nor whether it can be updated by the ST-LINK/V2-1 firmware. Adding further to the confusion, there is also a new variant of the ''Discovery kit with STM32F429ZI MCU'', marked ''STM32F429I-DISC1'', and it is said to have a ''ST-LINK/V2-B''. I'd love to hear an exhausting comment from an insider. JW

[S C]

Posted on April 14, 2016 at 10:08

Hello,

An answer to this question was already given recently in another topic:[DEAD LINK /public/STe2ecommunities/mcu/Lists/STM32Java/Flat.aspx?RootFolder=/public/STe2ecommunities/mcu/Lists/STM32Java/STLink%20V2%20versus%20V2-1&FolderCTID=0x01200200770978C69A1141439FE559EB459D758000F9A0E3A95BA69146A17C2E80209ADC21]https://my.st.com/public/STe2ecommunities/mcu/Lists/STM32Java/Flat.aspx?RootFolder=%2fpublic%2fSTe2ecommunities%2fmcu%2fLists%2fSTM32Java%2fSTLink%20V2%20versus%20V2%2d1&FolderCTID=0x01200200770978C69A1141439FE559EB459D758000F9A0E3A95BA69146A17C2E80209ADC21 Despite I understand you can not read all topics on our forum, I think you may at least read our answer to YOUR post. Moreover, the answer to your first 2 questions are in chapter 6.1 of the user manual of F4Discovery (UM1472), accessible from the dedicated web page for F4Discovery:

http://www2.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-eval-tools/stm32-mcu-eval-tools/stm32-mcu-discovery-kits/stm32f4discovery.html

In the same way, the firmware upgrade for this board is accessible from the same page, it's STSW-LINK007. I'm sorry if our website is currently having some troubles; I just checked myself that all links above are working properly. Best regards

[S C]

Posted on April 14, 2016 at 10:32

Hello,

An answer to waclawek.jan: First, thank you for your time answering this question; as regards the confusion, I perfectly understand. I hope the documentation helps clearing this confusion. My comment from an insider is that it is a consequence of the success of the mbed functionality on recent boards. Unfortunately, the initial F4 discovery board did not have the required hardware for supporting such functionality (the board was designed much before mbed). That's why V2-A and V2-B derivatives have been created afterwards, with the aim of providing this functionality on boards not initially designed for it ... So we should rather say ''ST did not foresee a future need for virtual com port and mass storage interface'' rather than ''ST forgot to connect the VCP''. All boards designed in the last 2 years are using the V2-1, designed for VCP and mass storage. Best regards

[waclawek.jan]

Posted on April 14, 2016 at 11:19

SC,

Thanks for your prompt answer. I am sorry, but that just raises further questions... > Unfortunately, the initial F4 discovery board did not have the required hardware for supporting such functionality (the board was designed much before mbed). Are you sure? My mbed account is from November 2010 (and mbed has been around for some time then, that was when I bought my first mbed gadget); and initial revision of UM1472 is dated 27-Sept-2011... OK, just some nitpicking... ;) > That's why V2-A and V2-B derivatives have been created afterwards, with the aim of providing this functionality on boards not initially designed for it ... So... Does this mean that the ''old'' STM32F4DISCOVERY's STLINK can be upgraded to the ''mbed'' variant? How? What does V2-A and V2-B then designate, exactly? Hardware connection of the STLINK STM32F103? Version of bootloader? Variant of firmware? All/any of these? How can V2-A  and V2-B be distinguished from V2-1 when connected to PC? What exactly are the differences? Are there any gotchas when moving between them? Why is no hardware connection for VCP on the *new* STM32F407G-DISC1? Was there any reason to retain the old layout partially/completely? Normally, these connections go through solder bridges; if there would be by-default-unconnected solder bridges for VCP, 100% compatibility signal-wise would be achieved, and with a bit of thinking, with only minor impact on performance (due to additional stubs on those two pins). OTOH, if the layout is completely untouched why the new designator then, causing confusion in webshops and your website (there's no STM32F407G-DISC1 in the list of DISCOs, for example)? And how is it with the firmware updates? As far as I know, there are two different lines of firmwares, and V2 STLINK cannot be field-upgraded to V2-1. Why? And what firmware is to be used to upgrade the V2-A and V2-B, if needed? The V2-1 firmware? Once at it, can you please explain the naming of the updates? Also, once at it, let me repeat my suggestion/request that ST provide the STM32F103 factory-programmed to STLINK (whatever version) as a part through the distributors (in a similar fashion as you provide dotnet- and JVM-programmed STM32F407). Thanks, Jan Waclawek

[S C]

Posted on April 14, 2016 at 14:57

Hello,

V2-A and V2-B designate both changes in hardware and different bootcode. We can also say it's the minimum changes required to make the VCP+mass storage firmware run on a V2 board. The reason why a full new F4Disco with real V2-1 ST-Link has not been made is an ST-internal decision. V2-A and V2-B provide the functionality under few conditions. Another possibility would have been to not provide the functionality on those old boards.

V2-A, V2-B and V2-1 boards can not be distinguished by the PC excepted by their mass storage volume name and mbed shortcut. But they all differ with V2 boards which enumerate on the USB with a single interface.

The STLinkUpgrade identifies the board type (V2 or not V2) and updates the firmware accordingly. As a result it's not possible to program a V2-1 firmware on a V2 board and conversely [otherwise this would be problematic afterwards]. The V2-1 firmware is designed

in such a way that he can also run on V2-A and V2-B boards. Few words about the version naming: J (for JTAG) is for the STM32 debug interface version; S (for Swim) is for the STM8 debug interface version; M (for mass storage) regroup the VCP and mass storage firmware version. For instance, STM32 discovery boards based on ST-Link/V2 (without mass storage + VCP) have version in the form V2J27S0, the ones based on V2-1 with mass storage and VCP V2J27M15.

I hope this clarifies a little bit more the topic. We are thinking about how presenting this more clearly. But the difficulty is to make simple the things that are not ;)

[richard239955_stm1]

Posted on April 14, 2016 at 15:28

Your response serves to highlight the poor design/capability of your support forum application.

I never received an email to my entry in the other form and could not find the entry to read it again. As the forum had exploded and crashed when I did the entry, I just assumed that wherever it was, it was dead. This is the first time I see an email indicating there is a response to my question and when I pull out my magnifying glass, I can almost read it. Have you folks thought about using different software that really works properly?

[Amel NASRI]

Posted on April 14, 2016 at 15:38

Hi tomkins.richard,

I agree that there are some issues with the forum.But you should be able to see the questions you submitted here clicking on ''My Discussions'' link. And if you activate an alert for a discussion, you will be able to receive any related update.-Mayla-

[AvaTar]

Posted on April 14, 2016 at 15:52

> Have you folks thought about using different software that really works properly?

Perhaps you have already noticed that this (i.e. ST's) user forum is based on MS SharePoint. Obviously, someone of questionable experience/competence made the decision for this software (not totally bad per se, but totally inappropriate for a user forum) years ago. And as long as the (perceived) pain of maintenance is smaller than the (perceived) pain of porting to something real, ST will continue to delight us with it. Since it is mostly a user supported forum, complaining vehemently, and en masse, seem the best way to transpire the pain toward ST ...

[Tesla DeLorean]

Posted on April 14, 2016 at 16:38

I was in the office with some of the ST staff yesterday discussing the forum and the issues here.

Over the years I've communicated with a number of groups within ST about the deficiencies in the Microsoft platform.The web portal is in the process of being overhauled, and hopefully some of the chronic issues with the platform can be addressed.With respect to the primary question, the new mbed ready ST-LINK uses a more powerful STM32F103 to provide the additional features, you can't flash the old parts with the new firmware.I think a chip level ST-LINK offering would be a good plan, similar to the ATMEL EDBG part.