Brymen BM789

[EEVblog]

I'm not aware of any Brymen DMMs that have updateable firmware...

The 78x series does.

[NoMoreMagicSmoke]

I'm not aware of any Brymen DMMs that have updateable firmware...

The 78x series does.

Dave are you allowed to say whether that programmer can/cannot read from the chip?

[EEVblog]

Dave are you allowed to say whether that programmer can/cannot read from the chip?

IIRC I tried that when I played with it and got nothing. So I presume it's protected.

[NoMoreMagicSmoke]

IIRC I tried that when I played with it and got nothing. So I presume it's protected.

I can't say I am surprised. With the lengths they went to obscure which chips are used I would be a bit perturbed if there wasn't some type of read protection. It's a bit of a bummer that you can't at least read out the EEPROM values within the CPU to enable repairability. Of course there are safety issues with doing modifications/repairs on a DMM, so probably for the best in this case.

[J-R]

I'm not aware of any Brymen DMMs that have updateable firmware...

The 78x series does.

OK, I have a BM789 that has old firmware, how can I get it updated?

[Neutrion]

Dave might does it for free.   Anyway I would also like to know, but I am afraid if there is no serious safety issue with the FW there is no such a service from Brymen.

Dave: Do you have any info about these new firmwares? Or any new ones for the 786?

[EEVblog]

OK, I have a BM789 that has old firmware, how can I get it updated?

As I mentioned in the video, you can't. It's just too expensive to ship it back and forth for a firmware update. I don't think any Brymen dealer is going to offer this as a service.
This is what I was afraid of with releasing that video, people asking to have their firmware updated.
You have to consider the BM78x like all other Brymen's, the firmware you get when you buy it is the firmware you have.

[EEVblog]

Dave: Do you have any info about these new firmwares? Or any new ones for the 786?

I have asked but I have not heard anything yet.

[J-R]

OK, I have a BM789 that has old firmware, how can I get it updated?

As I mentioned in the video, you can't. It's just too expensive to ship it back and forth for a firmware update. I don't think any Brymen dealer is going to offer this as a service.
This is what I was afraid of with releasing that video, people asking to have their firmware updated.
You have to consider the BM78x like all other Brymen's, the firmware you get when you buy it is the firmware you have.

Yes, I watched your video when it came out, as well as Joe's where he swapped chips.

So technically every Brymen probably can have it's firmware updated, but effectively none of them can from a user perspective.

But of course the BM78x sounds like it could be if someone takes a whack at it.

[EEVblog]

So technically every Brymen probably can have it's firmware updated, but effectively none of them can from a user perspective.

No, all other Brymen models use an OTP processor.
The 78x series is a new design that includes a flash based processor.

[EEVblog]

FYI

78608 version is only to enlarge allowance range for OHM hardware offset to reduce production failure rate. It does not affect meter performance.

[Fungus]

Somebody just opened a can of worms... 

[Antrus]

Found another annoying thing. In the video on YouTube, and checked it myself. In the region of 650 ohms and 6500 ohms, the multimeter cannot measure resistance in automatic mode. In firmware 78908-78910.

[joeqsmith]

Found another annoying thing. In the video on YouTube, and checked it myself. In the region of 650 ohms and 6500 ohms, the multimeter cannot measure resistance in automatic mode. In firmware 78908-78910.

I was able to replicated this with 08 and have contacted Brymen.   

[NoMoreMagicSmoke]

What's the symptom?

[Neutrion]

Did you manage to update the FW, or you have different meters?
BTW did the dc offset sinewave overload indication on the mV scale issue changed with any of the FWs? There was a debate whether it would be possible at all to solve that with any FW update.

[Monkeh]

Did you manage to update the FW, or you have different meters?

Only dealers have the programming tool and access to the firmware images, so it seems rather unlikely he updated it.

[joeqsmith]

Assuming you are addressing me,  I talked about the firmware updates throughout the videos for both the 786/9 meters.   As for DC biased waveforms, again, I supplied all that detail in the videos.

There was a bit of a discussion here (more than once) where a few beginners were asking about DC biased waveforms and I dove into it a bit further for them.  That's all online here. 

[Neutrion]

Sorry, I was actually adressing Antrus, but something went wrong it seems. But as long I remember you also have the 08.
Antrus seems to have tried two never versions.

[Antrus]

I have firmware 8. The person on YouTube has firmware 10. Of course, I haven't updated anything. The multimeter is almost 2 years old, but the manufacturer has not yet noticed such an obvious error in the firmware. Perhaps this resistance range is not needed by anyone.

[Constantin]

I have  Brymen BM 789, firmware 09 and It has no problems with the 650 Ohm and 6.5 kOhm measurement.

[Antrus]

Try measuring the variable resistor. In the range of 650-660 ohms in automatic mode, he goes crazy.

[joeqsmith]

I have firmware 8. The person on YouTube has firmware 10. Of course, I haven't updated anything. The multimeter is almost 2 years old, but the manufacturer has not yet noticed such an obvious error in the firmware. Perhaps this resistance range is not needed by anyone.

Did you bring it to their attention, or assume that posting to the EEVBLOG forum was the correct way to handle it? 
***
If you did write them, what was their response?  They have been very responsive when I have ask them questions in the past.

[Constantin]

Yes, I was able to find magical resistance, about 653 Ohms in my case :-)

[NoMoreMagicSmoke]

Try measuring the variable resistor. In the range of 650-660 ohms in automatic mode, he goes crazy.

I wonder if this is an issue with just some meters? I just tried with a potentiometer and s sweep from 600-700 6.0k - 7.0k could not cause the meter to freak out. My meter is 08 and it ranges up at 66000 counts and down at 61000 counts.

I did only have a 1 turn pot available though so it's possible it's a very narrow range and I didn't have the resolution on the potentiometer to hit the sweet spot.