Did we get an answer from OP yet? If not it's time to close the thread.
Did we get an answer from OP yet? If not it's time to close the thread.
I presume you mean the "answer" to the teaser?
Because OP's original question has been answered: it is somewhat common, and without more info I suspect the EEVblog 121GW is most likely more hackable due to the published schematic and microSD slot.
Plus, some significant work has already been done on reverse engineering the 121GW beyond the schematic ...
https://github.com/tpwrules/121gw-reIf you just want a well documented multimeter circuit to hack into your own design, then Digilent have this
https://store.digilentinc.com/dmm-shield-7-function-digital-multimeter-shield/
Did we get an answer from OP yet? If not it's time to close the thread.
No, the OP hasn't been back on EEVblog since three days. Busy building his new multimeter business, or turning his scoop into a full-length movie, I presume.
For a fully functional multimeter with a mature firmware , what is the point for "hacking" ? You can't add features or improve it . The 121GW , as it is now , is not used to the max and has some deficiencies, that why the haching and improving the firmware could be very usefull .
Yes, well-made video. 
Thanks, im very new to all this. Glad you liked it.
Did we get an answer from OP yet? If not it's time to close the thread.
No, the OP hasn't been back on EEVblog since three days. Busy building his new multimeter business, or turning his scoop into a full-length movie, I presume.
Haha, you have no idea. Filming and editing the video has been non stop for the full week. Even deciding if i should just do a basic unboxing or go into deeper depth wasn't easy to decide as you can see from some of the comments here. I have been editing for 5 days solid and the result is a 12 min video lol. Don't know how most youtubers manage to release content so fast.
Haha, you have no idea. Filming and editing the video has been non stop for the full week. Even deciding if i should just do a basic unboxing or go into deeper depth wasn't easy to decide as you can see from some of the comments here. I have been editing for 5 days solid and the result is a 12 min video lol. Don't know how most youtubers manage to release content so fast.
We can talk again one year from now when you released a lot more videos... With time you will start getting shortcuts and knowing where everything is plus improving your workflow.
Did we get an answer from OP yet? If not it's time to close the thread.
I presume you mean the "answer" to the teaser?
Because OP's original question has been answered: it is somewhat common, and without more info I suspect the EEVblog 121GW is most likely more hackable due to the published schematic and microSD slot.
Plus, some significant work has already been done on reverse engineering the 121GW beyond the schematic ... https://github.com/tpwrules/121gw-re
If you just want a well documented multimeter circuit to hack into your own design, then Digilent have this https://store.digilentinc.com/dmm-shield-7-function-digital-multimeter-shield/
In many ways this was the scope of the question, to establish if id found gold or tin. I haven't taken apart enough meters to know if the STM32L152 is common amongst them or if its a rarer find. I also come from more of a hacking background so like to tweak things to do things they shouldn't. Someone joked about Tetris, i have a remote control I've made do that already lol. Even making it flash on continuity would be useful to someone. I think id feel warm inside if i powered it up and it said PWND but hey, its the little things.
I think you can see from my video and the way i went about it that i didn't want to make just another multimeter video (even if some would have preferred that) because it isn't me. I prefer to try and find out what something can't do rather than just see what it already does.
here is a teaser
Teaser? 
Can't you tell make and model of multimeter? Yes, indeed there is stm32 inside. So what? Most likely you can't read-out it's firmware anyway (unless you are ready to invest significant amount of money). It means no *hacking*. You have to swap chip on PCB with new one and *develop* stm32 code from grounds-up. Before that you have to reverse-engineer and analyze circuit of device to fully understand it's operation so you can write code that actually works. All that for what exactly? - To prove that you can do it? Good luck with that. I mean it.
"Improvement"of instruments is recurring topic here. Most of those who actually want to use instruments will just use them as is. Serious engineer do not want to debug device he is building with tool he can't rely-on, that needs to be debugged itself.
All good points and i don't disagree with anything you have said. I wasn't looking to offend with the term Teaser. Please allow me some intrigue for the efforts I've made to make a video review of a meter that isn't commonly known. I hope you have enjoyed the video and at least its a tiny bit more insight than the community otherwise had into this product. My channel isn't monetised as i don't have enough subscribers or views yet so this is a lot of work for no financial reward (over a weeks worth). Im hoping i can make content that gets views over time rather than just over the first few days. Its an early first effort at doing a proper review and promoting it. Don't be too harsh lol.
Did we get an answer from OP yet? If not it's time to close the thread.
No, the OP hasn't been back on EEVblog since three days. Busy building his new multimeter business, or turning his scoop into a full-length movie, I presume.
No multimeter business, just trying to make a youtube channel worth watching. I guess i didn't realise how tough the audience is lol.
Haha, you have no idea. Filming and editing the video has been non stop for the full week. Even deciding if i should just do a basic unboxing or go into deeper depth wasn't easy to decide as you can see from some of the comments here. I have been editing for 5 days solid and the result is a 12 min video lol. Don't know how most youtubers manage to release content so fast.
We can talk again one year from now when you released a lot more videos... With time you will start getting shortcuts and knowing where everything is plus improving your workflow.
My experience of Final Cut Pro is this one video, im learning as i go.
Im hoping i can make content that gets views over time rather than just over the first few days. Its an early first effort at doing a proper review and promoting it. Don't be too harsh lol.
No worries. Production quality is very good, well above average in the category. Looks like expensive enough commercial
Impressive start. Hope that you have next trick in your sleeve already.
Video is good , but implying is a competitor or somewhat equivalent to Fluke 87-V is a little farfetched if you look at the specs ... I don't think you will get many viewers with such exaggerations
Wow that's some compliment for my first proper video. Thanks, glad you liked it. I had an idea in my head how i wanted it to look but once you start adding flashy FX it does start to look like an advert lol. I tried to rein it back in but i also wanted it to look as professional as possible as im trying to improve my production quality as time goes forward. This video literally felt like it took an age to make but its worth it if people like it. I have seen loads of other DMM videos and many are a lot more technical than i was able to get so i made up for that with 4K and some additional info. Glad you liked it, hope you subscribe.
Video is good , but implying is a competitor or somewhat equivalent to Fluke 87-V is a little farfetched if you look at the specs ... I don't think you will get many viewers with such exaggerations
I wasn't trying to exaggerate. Its clear that's what the Product is targeting even if it may fall short in some areas. I have made clear comparisons in the video where they have even appeared to copy some of the Fluke design. I would say the input protection is every bit as good as the Fluke 87V and the board is much more modern in its design and layout. I never gave it a 10 star review and i have been critical in the areas i could see where it fell short. I couldn't put everything or the video would be twice as long and it would have lost the viewer. I watch it and know there were things i forgot to mention but once its up its up. Megger is a very reputable brand here in the UK, every bit as reputable as Fluke and they specialise in much more expensive equipment than the DMM i reviewed. In many ways its a small device to them in the big machine that is Megger.
Damn good video! Can't wait to see what else you come up with.
Damn good video! Can't wait to see what else you come up with.
Maybe I will even surprise myself, thanks.
Video is good , but implying is a competitor or somewhat equivalent to Fluke 87-V is a little farfetched if you look at the specs ... I don't think you will get many viewers with such exaggerations
I wasn't trying to exaggerate. Its clear that's what the Product is targeting even if it may fall short in some areas. I have made clear comparisons in the video where they have even appeared to copy some of the Fluke design. I would say the input protection is every bit as good as the Fluke 87V and the board is much more modern in its design and layout. I never gave it a 10 star review and i have been critical in the areas i could see where it fell short. I couldn't put everything or the video would be twice as long and it would have lost the viewer. I watch it and know there were things i forgot to mention but once its up its up. Megger is a very reputable brand here in the UK, every bit as reputable as Fluke and they specialise in much more expensive equipment than the DMM i reviewed. In many ways its a small device to them in the big machine that is Megger.
A small advice ... you have to be impartial to be succesfull in this area , I see that you a very big Magger's fan
, or they pay you to do it .
Video is good , but implying is a competitor or somewhat equivalent to Fluke 87-V is a little farfetched if you look at the specs ... I don't think you will get many viewers with such exaggerations
I wasn't trying to exaggerate. Its clear that's what the Product is targeting even if it may fall short in some areas. I have made clear comparisons in the video where they have even appeared to copy some of the Fluke design. I would say the input protection is every bit as good as the Fluke 87V and the board is much more modern in its design and layout. I never gave it a 10 star review and i have been critical in the areas i could see where it fell short. I couldn't put everything or the video would be twice as long and it would have lost the viewer. I watch it and know there were things i forgot to mention but once its up its up. Megger is a very reputable brand here in the UK, every bit as reputable as Fluke and they specialise in much more expensive equipment than the DMM i reviewed. In many ways its a small device to them in the big machine that is Megger.
A small advice ... you have to be impartial to be succesfull in this area , I see that you a very big Magger's fan , or they pay you to do it .
No not a fan of the brand as such. I used to have an old AVO2007 when I was 10 that was handed down from a close family member and always loved its industrial design. That was a Metrawatt device they branded. I was recently looking for a new meter myself and started my research here then during my search I thought id check out Megger after trying to find the modern replacement for my old AVO. If you search my posts here you will find that. I then settled on the Yokogawa meter as it felt closest to my aspiration in industrial design but Joe Smith put me off it with his review when it didn't register dangerous voltages. So I decided to take advice given here and got the Brymen 869S which I am very pleased with. I later looked into the Megger AVO835 some more as I liked the look of it but I couldn't find any reviews of it on YouTube bar 1 which was just an unboxing. After talking with Joe he suggested I do my own review of it as I was curious still so the rest is history. I like the device and I had very high hopes for it as its British designed, the more I dug I to it the more I liked it. Is it perfect? no, but its still a nice meter that shouldn't be ignored. My Channel is very new and it's not even monetised, I've made the extra effort in case another brand wants me to check out their gear so I can build my channel. I 100% agree about being impartial, you think they would pay me to chuck their probes in the bin and slate their accessories? I live in Brexit Britain and wanted to see what we had to offer in the space, I wasn't dissapointed with the meter itself, inside its a work of Art.
No. You can't wipe nor reprogram RDP2-protected stm32.
I have not worked with ST parts now for more than 5 years but I thought that using SWD/JTAG to disable RDP2 would result in wiping the flash and hence allow reprogramming. My bad if I am wrong.
how do we know they bothered to encrypt it?
No. You can't wipe nor reprogram RDP2-protected stm32.
I have not worked with ST parts now for more than 5 years but I thought that using SWD/JTAG to disable RDP2 would result in wiping the flash and hence allow reprogramming. My bad if I am wrong.
how do we know they bothered to encrypt it?
Solder debug connector, connect debug adapter and check using stm32 debugger or st-link utility - MCU responds to debug interface or not (debugger can ID chip). Be careful doing that - do not execute erase. Such error will brick your device.
excellent well that confirms what I had planned anyway. let's see what happens. Daves video on the STM32 micro was very interesting