I´m trying to get my recently bought “TouchDRO iGaging BlueTooth DRO adapter” and a pair of 20” / 500mm Shahe scales to work… with limited success. The scales, see image attached, have separate displays. Both scales work fine with both displays. One scale is working with the BT adapter, but shows a strange effect and the other one is not working at all with the BT adapter. Power on the board, start the app, the sensor is somewhere in the middle of the scale. I shift the sensor to one end of the scale and set the axis to zero in touchDRO. If I shift the sensor towards the other end, the value in the display rises, as expected, but from about 70% of the scale´s length, the displayed value decreases again. Shifting the sensor back to the “0” positon results also in display 0. If I position the sensor at one end of the scale BEFORE I power on the board or plug in the sensor, the effect described above doesn´t show. Also with the original displays this doesn´t happen. Regarding the second scale, that doesn´t work at all with the BT adapter, I have no clue yet. Seems I have to get the oscilloscope from the shelf and do some research.
I was hoping to have a plug and play solution by buying one of the assembled boards…
(11-13-2017, 01:41 PM)lushifushi Wrote: I´m trying to get my recently bought “TouchDRO iGaging BlueTooth DRO adapter” and a pair of 20” / 500mm Shahe scales to work… with limited success. The scales, see image attached, have separate displays. Both scales work fine with both displays. One scale is working with the BT adapter, but shows a strange effect and the other one is not working at all with the BT adapter. Power on the board, start the app, the sensor is somewhere in the middle of the scale. I shift the sensor to one end of the scale and set the axis to zero in touchDRO. If I shift the sensor towards the other end, the value in the display rises, as expected, but from about 70% of the scale´s length, the displayed value decreases again. Shifting the sensor back to the “0” positon results also in display 0. If I position the sensor at one end of the scale BEFORE I power on the board or plug in the sensor, the effect described above doesn´t show. Also with the original displays this doesn´t happen. Regarding the second scale, that doesn´t work at all with the BT adapter, I have no clue yet. Seems I have to get the oscilloscope from the shelf and do some research.
I was hoping to have a plug and play solution by buying one of the assembled boards…
Karsten
Karsten,
Sorry you are having a problem.
The board is generally plug-and-play, but unfortunately scales you got are the newer model that is not supported yet. I can't get a hold of one to test (ordered from Aliexpress twice and both got "lost"). A few people were able to use those scales but looks like there is something weird that happens with longer scales.
Until I find a scale to test in the States, I can't really tell you what the problem is. If I'm not mistaken you are in Germany, right? If the board is in "like-new" condition you can send it back to me and I will refund the cost of the board.
Thanks Yuri for the swift reply.
For the scale that doesn´t work with the board, but the original display, I found out that it transmits three datasets after connection, but then stops. Signal amplitude is 2,5v pp, is this what the board expects?
The protocol looks quite simple, is the signal timing , clock frequency critical for your board, maybe this is something that has changed with this type of scale? I could send you a scope screenshot, if that would help.
(11-14-2017, 08:49 AM)lushifushi Wrote: See screenshot below, scale connected to the BT adapter.
six nibbles ... BIN6 ?
I tried to get a BIN6 scale to work on the Mixed Scale board and found that it didn't understand negative numbers. You have a scope. Watch for the MSB to change and see if that's when your values go wrong. I posted about it here at the time.
I've equipped both my lathe and mill with Shars aluminum scales. There is no practical difference between them and the stainless scales, and they're a lot easier to work with (and Shars has them on sale). I have no affiliation with Shars other than as a satisfied customer. They are working great, but I had to add supply decoupling capacitors in the read heads on the lathe for stability. I had a LED lamp that really made them go crazy before I installed the caps. The mill that I'm working on now doesn't seem to have the same problem, but I may do the mod anyway just to be sure.
It seems the iGaging board has the mixed scale firmware, that´s why it works somehow with the BIN6 scales, but the signal level of one of them is just out of range and needs a voltage shifter.
(11-14-2017, 04:44 PM)lushifushi Wrote: It seems the iGaging board has the mixed scale firmware, that´s why it works somehow with the BIN6 scales, but the signal level of one of them is just out of range and needs a voltage shifter.
The firmware is different from the mixed scale but the board can confuse BIN6 for IGaging Absolute protocol. It will even work to a degree, but won't interpret negatives, etc.
If someone can point me to one of those scales for sale in the USA (or lend me one for a few weeks) I will be happy to test it and update the firmware. I don't think it will be that much work...
You are mentioning there: "The 21-st bit indicates the negative number" This is what I see also here, but the software doesn´t seem to process this bit.
"Additionally there is no evidence that all of the first 20 bits are used. Using 16 bit..." Well, here is the evidence, this scale uses 17 bits but the software seem to process the first 16 bit only.
Without the original dislpay connected, I can´t switch mm/inch mode. Bits 22...24 are always 0.
You are mentioning there: "The 21-st bit indicates the negative number" This is what I see also here, but the software doesn´t seem to process this bit.
"Additionally there is no evidence that all of the first 20 bits are used. Using 16 bit..." Well, here is the evidence, this scale uses 17 bits but the software seem to process the first 16 bit only.
Without the original dislpay connected, I can´t switch mm/inch mode. Bits 22...24 are always 0.
Karsten
Karsten,
Thank you for the information. This is very helpful.
Mixed scale firmware handles negative numbers using bit 21, so this scale is slightly different. If you are 100% positive this is the case I can compile a "custom" version of the firmware for you to try over the weekend.
but the software seem to process the first 16 bit only.