TouchDRO with old Acu-Rite scales

[RichT]

Hi All,
I have a early 90's knee mill that I bought used. It came with Acu-Rite scales but no DRO. I have been looking at TouchDRO and I'm really impressed. Yuriy, if you're reading this, thank you for creating such an awesome app and sharing it with the world!

I don't see any identifying marks on my reader and it doesn't appear to have the more modern chipset shown in the TouchDRO article "Finding Glass Scale Pinout". I'm attaching some pic's to see if anyone recognizes these scales and can help me determine if they will work with TouchDRO. I already ordered the V2 adapter and installed the app. I figure that I can replace the scales if I have to, but I'm really hoping to use them as they're probably decent quality -assuming they work.

 

[RichT]

I found something that looks similar in the obsolete manuals section of the Acu-Rite website. There's a PDF file "MiniMateScaleMan.pdf". My system uses rectangular (D-Sub 9) connectors.

If this is the correct model, my interpretation would be to connect the wires as follows:

Pin 1 -> GND
Pin 2 -> A
Pin 3 -> A'
Pin 4 -> B
Pin 5 -> B'
Pin 7 -> +5V

I'm cautiously optimistic that this might actually work with my existing scales!

 

[ycroosh]

I found something that looks similar in the obsolete manuals section of the Acu-Rite website. There's a PDF file "MiniMateScaleMan.pdf". My system uses rectangular (D-Sub 9) connectors.
View attachment 449433

If this is the correct model, my interpretation would be to connect the wires as follows:

Pin 1 -> GND
Pin 2 -> A
Pin 3 -> A'
Pin 4 -> B
Pin 5 -> B'
Pin 7 -> +5V

I'm cautiously optimistic that this might actually work with my existing scales!

Rich,
These look like standard "differential" scales, and should work well with TouchDRO.
I'm a bit surprised that scales from the 90's use this protocol. So far, I haven't run across any that were 5V. I wonder if they are a more recent addition. (this is besides the point).

Regards
Yuriy

 

[RichT]

Rich,
These look like standard "differential" scales, and should work well with TouchDRO.
I'm a bit surprised that scales from the 90's use this protocol. So far, I haven't run across any that were 5V. I wonder if they are a more recent addition. (this is besides the point).

Regards
Yuriy

Thanks Yuriy! It looks like I got lucky. My adapter is 'out for delivery' today -just in time for the weekend!

Hopefully the scales on the machine are still in working condition. The original DRO had already been removed when I got it. I've got my fingers crossed that they will just work, but if not it shouldn't be a big deal to replace them.

BTW, I hope you don't mind that I posted here instead of your site. My account hasn't been verified so I currently only have read access.

Thanks again for your support!

 

[RichT]

The Bluetooth is connected and the DRO reads 0.0000 for all axes. Unfortunately, moving the table didn't register any movement on the DRO. The same thing is happening on both X and Y axes. The 'guts' of my reader doesn't look anything like the one in the "How to find glass scale DRO pin functions" article but I'll dig deeper over the weekend.

 

[ycroosh]

The Bluetooth is connected and the DRO reads 0.0000 for all axes. Unfortunately, moving the table didn't register any movement on the DRO.

My documentation uses A+, A- instead of A, and A'. I'm tempted to try swapping the A and A' and B and B' since it's powered up and communicating to the DRO and the same thing is happening on both axes.

If you own a voltmeter, I would recommend the following:
1. Open one of the D-Sub connectors to confirm the wiring is correct.
2. Connect Ground and Vcc to the board (looks like White and Brown).
3. Probe between Ground and the data lines. Make sure you get 5V (might need to move the head a bit back and forth)
4. Move the head around and see which lines change in unison, and which are a bit off.

Basically, you need to figure out if the connection diagram is accurate, and that the scale is working.

Regards
Yuriy

 

[markba633csi]

I don't think swapping the data polarity would be the issue- must be something else

 

[RichT]

If you own a voltmeter, I would recommend the following:
1. Open one of the D-Sub connectors to confirm the wiring is correct.
2. Connect Ground and Vcc to the board (looks like White and Brown).
3. Probe between Ground and the data lines. Make sure you get 5V (might need to move the head a bit back and forth)
4. Move the head around and see which lines change in unison, and which are a bit off.

Basically, you need to figure out if the connection diagram is accurate, and that the scale is working.

Regards
Yuriy

Thanks again Yuriy! I'll give this a try.

 

[RichT]

I don't think swapping the data polarity would be the issue- must be something else

Thank you for your reply. I did some more reading after I posted and learned a bit more about 'differential scales' and I 100% agree with you. I'm going to try probing the pins tomorrow as Yuriy suggested to see if I can get the data lines figured out. The previous owner may have rewired things so it's worth a try before running out and replacing potentially good Acu-rite scales with imports -which is still plan 'b' if needed.

 

[RichT]

If you own a voltmeter, I would recommend the following:
1. Open one of the D-Sub connectors to confirm the wiring is correct.
2. Connect Ground and Vcc to the board (looks like White and Brown).
3. Probe between Ground and the data lines. Make sure you get 5V (might need to move the head a bit back and forth)
4. Move the head around and see which lines change in unison, and which are a bit off.

Basically, you need to figure out if the connection diagram is accurate, and that the scale is working.

I finally had a chance to check into it and the wire colors match the manual, but there was no reading on any of the data lines. Looks like I'll be shopping for some new scales.