Crazy high CPI and no minus?

[NormanP]

Hi all,

Has anyone been successful in using this scale from Arceuro?

https://www.arceurotrade.co.uk/catalogue...b100c1d409

The scale connects OK but the CPI has to be set at approx 508000 in order to read accurately. I'm using the Universal_V1.0.hex firmware,

In addition, the DRO does not show minus values even when the scale itself shows minus.

Any info appreciated, even if it is just to confirm I'm wasting my time trying to solve this. Thanks.

[Yuriy]

It depends on what the scale outputs. If the reading is correct, there is nothing wrong with that CPI.

[NormanP]

Hi Yuriy, thanks for getting back and for reassuring me on the high CPI.
Any thoughts on the lack of minus readings? (that's probably the more fundamental concern for me). The scale itself (when moved) displays +ve through zero to -ve but the DRO shows +ve through zero and then +ve again.
For info - the scales run from a single 3v cell but the signal is 1.5v.
Thanks again for your thoughts on this.

[NormanP]

Unfortunately I cannot get past the lack of minus readings - any suggestions or info would be very welcome. They are a decent looking stainless scale but if I've got to send them back then I've got limited time to do it and as we're shielding and in full "Corona lock down" it's going to be tricky!!
Yuriy - if there's a paid for version of the firmware that would fix the issue then please let me know, I'd happily look at that. Thanks.

[Yuriy]

I suspect your scales use the new Shahe electronics (the sign bit is in a different position). The firmware that ships on pre-made boards and the new kit should support it. I need to recompile and upload the file to the site; if the weekend doesn't go completely to crap I should be able to do it before Monday.
Regards
Yuriy

[NormanP]

That would be great and very much appreciated - thanks Yuriy!

[NormanP]

Hi Yuriy, did you get a chance to look at recompiling a version of firmware? (I'm currently using your v1.0 Mixed Scale release). These scales seem to have a pretty good resolution, stainless rail hardware, -ve ground and can be used with off the shelf fully screened mini usb leads. The lack of minus readings at the DRO being their big Achilles heal!!  
If a firmware update is not an option then I need to get these scales returned asap (Covid lockdown permitting!). I can dig out an old oscilloscope and try to get some photos of the clock and data signals if that helps? Thanks again for your help and support  Yuriy.

[NormanP]

I've attached a screenshot of the scale outputs - does anyone recognise the coding format? Upper trace is the clock and lower is the data.

Any and all help appreciated - Thanks!

---

By pure chance.... I read a post from 2017:

https://forum.yuriystoys.com/showthread.php?tid=146

It describes the same problem and pointed me in the direction of an earlier firmware release (v0.3). I've tried loading v0.3 and found 2 changes:

- the CPI now has to be set at half the previous rate (so approx 254,000 instead of 508,000)

- the minus sign now works correctly

So I suspect something happened in the Bin6 interpretation somewhere between v0.3 and v1.0 - anyone recall or know anything on this?

Thanks for any info.