Search found 16 matches

by iotexpert.com
Wed May 09, 2018 4:01 pm
Forum: GTT Series
Topic: I2C Stops Working
Replies: 7
Views: 11802

Re: I2C Stops Working

Turns out that there is some bug in 2.10xx firmware... and in fact 2.9xxx firmware.

A workaround to unbrick the display is to install 2.4 firmware... then reinstall 2.10
by iotexpert.com
Sun May 06, 2018 11:35 am
Forum: GTT Series
Topic: GTT43a I2C Bug
Replies: 3
Views: 9494

GTT43a I2C Bug

I have a loop that does I2C reads... essentially like this while(1) { x = read print x } When you run this you will get 0's ... until there is something in the buffer... this is good. I have a screen with a legacy button. Every time you press the button it puts 252,135,0,2,0,7 into the buffer... whe...
by iotexpert.com
Fri May 04, 2018 9:32 am
Forum: GTT Series
Topic: GTT 2.5 Driver License
Replies: 1
Views: 8386

GTT 2.5 Driver License

There is a pretty coherent library here: https://github.com/MatrixOrbital/GTT-Arduino-Thermometer-Demo/tree/master/GTT%20Client%20Library/GttClient That seems to implement the GTT25 protocol (code 250)... which is super useful given that I dont see any documentation for it. So my question is... what...
by iotexpert.com
Thu May 03, 2018 1:38 pm
Forum: GTT Series
Topic: Text Toggle Button
Replies: 2
Views: 8659

Re: Text Toggle Button

I have been looking at driver libraries... There are tons of commands which I can see that are not documented... they all seem to fall into the "GTT25" ... presumably the 25 is a new protocol? I am really hoping there is some documentation so I dont have to reverse engineer it... as I am b...
by iotexpert.com
Thu May 03, 2018 10:33 am
Forum: GTT Series
Topic: Text Toggle Button
Replies: 2
Views: 8659

Text Toggle Button

I have three questions about the Text Toggle Button #1. I notice that when I press the button I get 252,250,0,3,1,10,254 ... however code 250 is not documented in the GTT Protocol V2.6 documentation. Am I looking at the wrong manual? If so where do I get the right one. #2... are there other undocume...
by iotexpert.com
Thu May 03, 2018 9:40 am
Forum: GTT Series
Topic: I2C Stops Working
Replies: 7
Views: 11802

Re: I2C Stops Working

Well.

I got a new display today. I plugged it into the same setup and it works.

I suppose my other one has a blown up I2C... which sucks

How do I RMA it?

Alan
by iotexpert.com
Tue May 01, 2018 11:21 am
Forum: GTT Series
Topic: I2C Read with GTT43
Replies: 24
Views: 25367

Re: I2C Read with GTT43

Awesome. Thank you that helps a lot.
by iotexpert.com
Tue May 01, 2018 11:19 am
Forum: GTT Series
Topic: I2C Stops Working
Replies: 7
Views: 11802

Re: I2C Stops Working

Yes I have tried multiple I2C addresses.

Yes I have 2.2K pull-ups... (it was working).

Is there some setting that turns I2C on/off in the screen? Could I have changed something?

At this point all I can figure is that I blew up something.

Alan
by iotexpert.com
Mon Apr 30, 2018 1:38 pm
Forum: GTT Series
Topic: I2C Read with GTT43
Replies: 24
Views: 25367

Re: I2C Read with GTT43

Thank you that is helpful. Having complete messages is good.

One more question... what happens if the display needs to over-run the buffer? Does it throw out earlier stuff? Or not write into it?
by iotexpert.com
Mon Apr 30, 2018 1:36 pm
Forum: GTT Series
Topic: I2C Stops Working
Replies: 7
Views: 11802

Re: I2C Stops Working

I can still write to it via the serial port... yes... using the UART I can send 254 88 and I get a clear screen... and I can read as well. What I cannot do is talk to the display via I2C. All writes and reads of the device are NAK I suspected that it might be a power problem (from another thread) so...
by iotexpert.com
Sun Apr 29, 2018 5:07 pm
Forum: GTT Series
Topic: I2C Stops Working
Replies: 7
Views: 11802

I2C Stops Working

I am able to talk to the GTT43A via Serial and via the Mass Storage.

I am no longer able to talk via I2C.

For the life of me I can't figure out what I could have done to turn off the I2C.

Does anyone have any idea?
by iotexpert.com
Fri Apr 27, 2018 2:56 pm
Forum: GTT Series
Topic: I2C Read with GTT43
Replies: 24
Views: 25367

Re: I2C Read with GTT43

I tried reading bytes to try to clear out the buffer... Looks like after I read about 25 bytes the buffer is clear... And then my commands work correctly (this is good). 1) is there a way to know how many bytes are in the buffer? 2) are there always complete responses in the buffer (meaning I could ...
by iotexpert.com
Fri Apr 27, 2018 2:48 pm
Forum: GTT Series
Topic: I2C Read with GTT43
Replies: 24
Views: 25367

Re: I2C Read with GTT43

OK. I understand... I think. I think you are saying that I can setup things with GTT designer and set the communication to none... then after the system boots, I can send an I2C command to set the channel to I2C Or I can read the data until the buffer is clear. Is there a command to clear the I2C bu...
by iotexpert.com
Fri Apr 27, 2018 9:54 am
Forum: GTT Series
Topic: I2C Read with GTT43
Replies: 24
Views: 25367

Re: I2C Read with GTT43

Is there an I2C protocol timing diagram in some document? If so I haven't been able to find it... but I would love to see it.
by iotexpert.com
Fri Apr 27, 2018 9:53 am
Forum: GTT Series
Topic: I2C Read with GTT43
Replies: 24
Views: 25367

Re: I2C Read with GTT43

Yes... but I guess that I dont understand why having or not having screens in there would impact the I2C interaction.

In other words... it seems to me that I would be able to do a "protocol version" read regardless of anything?