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G120HDR with Sytech 4.3" / CP7


Hi All,

With the information from Aron in this post I have a T35 display working successfully on my G120HDR v1.1 running firmware v4.2.7.0. The test code is a NETMF 4.2 application, I am using the Tinkr library for the UI but I didn’t need to put in any specific code for the display, sockets or the touch interface.

I then tried a Sytech 4.3" display and unfortunately the Touch interface isn’t working, the graphics/display work ok but not the touch. The Sytech display has been tested on my Spider board so I can verify this works, the cables are the same as used for this as well so I know they are fine. Comparing the Gadgeteer driver code (Found on the Gadgeteer CodePlex) I can’t see anything different between the displays so it doesn’t look like any special settings are required.

Other than the change in LCDConfig settings I didn’t think there would be any difference between the configurations. I also have a CP7 display that I would like to test with the G120HDR but this fails to work as well. So, after all these ramblings I have the following questions :

a. Is there any way LCD Config settings could affect the Touch interface ?
b. Should I need to write any specific code for the G120HDR in a NETMF application for either display ? If so, any ideas/snippets would be great
c. After reading a lot about the G120HDR touch interface I am still unsure whether the CP7 is currently supported, is it ? If so what needs to be done ?
d. Any other ideas ?

I currently have a Spider, Hydra and G120HDR on my desk next to the T35, 4.3" and CP7 so have a lot of permutation and combinations to get through ! Hopefully I can finish this evaluation phase soon and crack on with the next phase of product development.

Many thanks in advance, Swifty.


LCD config are not related to touch.

Did you calibrate the touch? There is an example that ships in the netmf SDK.


HI Gus,

Thanks, I didn’t think that the LCD config was related but being the only thing that changed I wanted to make sure.

I did a manual SetCalibration(…) with numbers from the NETMF SDK example run on the Spider.



The spiders numbers are not for your display so these won’t work. See this please C:\Users\Gus Issa\Documents\Microsoft .NET Micro Framework 4.2\Samples\TouchCalibration
What you really need to know is that whether the touch is not working at all or it is off.

I am not sure how much we can help since we do not have your display. If it was one of our then this would have been easier.


Hi Gus,

The numbers I used were from the TouchCalibration example you suggested running on a Spider with the Sytech 4.3" display, this was one of the first tests I did and the touch worked fine. I thought the numbers were associated with the display and not the processor board, have I misunderstood this ? I will run the calibration example again on the G120HDR hardware and report the results I get.

I understand that the display is not a GHI product, I do appreciate your help and support with the interfacing.

What about the CP7 ? Should this be working with the G120HDR and has it been tested ?

Thanks again, Swifty.


I never seen that display so I am not sure how I would suggest some values :slight_smile: Where did you see this info?

We are ready to help always, just saying that I am guessing the answers but will keep trying :slight_smile:

CP7 is capacitive display that touch is capacitive and work on I2C but. These displays have amazing muti-touch interface and it is as smooth as the touch in any modern phone, like iPhone.


Sorry Gus, looks like there has been some confusion here. I ran the TouchCalibration example (The same one you suggested) on a Spider board that I connected to the Sytech display, I then logged the calibration data from this test. After this I setup the G120HDR and Sytech and used the logged values from the initial test.

Am I correct in thinking that the values logged from the initial test are ok to use with the same display on a different microprocessor board ? Or will a different board with the same display produce different numbers ?

Has the CP7 been tested on the G120HDR ?

With the wiring I have will it work ?

I know the CP7 is a lovely display, unfortunately I have been dissappointed with this in combination with the Spider. I am working on a couple of different products that will be low volume, 25+ a year and althought this could be higher I do need off the shelf components because the volumes do not support a full custom design. From some initial research I purchased a Spider and CP7, initially things looked good but then I stumbled across the microSD card causing jitter on the CP7 display and also the UI felt a little lethargic and not as responsive. It seems as though the CP7 resource requirements are beyond the Spider’s capabilities and so I have been looking for alternatives.

There are obviously 2 avenues to improve performance, reduce the display resource requirement and/or improve the microprocesser performance. The T35 is too small and unfortunately (As has been discussed on the forums already) there is no GHI offering for a 4.3" display. At the moment I have the Sytech 4.3" display as well as a serially controlled display on evaluation, I also purchased a Cerberus, Hydra and G120HDR to evaluate and hopefully give me a nice solution that doesn’t have the niggling issues I have described above. The CP7 would be the prefered choice if I can get the processor performance.

I agree with your comments on the CP7, it is a lovely display, crisp, clean, responsive and certainly offers a premium looking appearance. This is the reason I would like to test it with the G120HDR, on paper this should out perform the Spider, however I have learned that there is no substitue for empircal results when it comes to microprocessor development.

If you are able to help with the CP7 that would be great, I will re-test the Sytech board again tomorrow morning as it is getting late here in the UK.

Cheers, Swifty.


[quote]Am I correct in thinking that the values logged from the initial test are ok to use with the same display on a different microprocessor board ? Or will a different board with the same display produce different numbers ?
Oh I see. EMX and G120 are very similar so it is possible that may work but in general no that won’t work.

[quote]Has the CP7 been tested on the G120HDR ?
Not myself but we can grantee it will work.

I understand now. The problem is not the display but in the jitter caused by mainboard being overloaded. I am curious now if there is any jitter when using G120. Let me run some tests and get back to you on this.

By the way, GHI will has a new 4.3 display offer. It should be up in a week or two.


Evening All,

I am banging my head against a brick wall here and hope that someone might be able to help. Further to all of the above I am still struggling to get the G120HDR v1.1 board running with the Sytech display and also the CP7. So I have 2 issues :

a. G120HDR -> CP7

I currently have the following connections :
Socket Pin 3 (GPIO!) – P0.23
Socket Pin 6 (GPIO) – Not Connected
Socket Pin 8 (SDA) – P0.27
Socket Pin 9 (SCL) – P0.28

Is this correct ? If not, what should it be and where should Pin 6 be going ?

b. G120HDR -> Sytech

I have a T35, this works perfectly with the following connections :
Socket Pin 4 (YU) – P0.24
Socket Pin 5 (XL) – P0.23
Socket Pin 6 (YD) – P1.0
Socket Pin 7 (XR) – P1.1

The display and touch both work as expected. The same connections with the Sytech and the touch does not work, I find this very puzzling because both of these displays work with the Spider and the Sytech display is expecting a T socket as the T35 is. I have written my own class for the Spider/Sytech to ensure that it works without any unusual code or connections and it is fine.

Any ideas why 2 different displays show different results and where I should start looking for the problem ?

I have a customer presentation tomorrow to show the range of displays 3.5", 4.3" and 7" and also the different processor boards, Spider, Hydra and G120HDR. As soon as the GHI 4.3" display is available I will be getting hold of one as quickly as possible so I am working in an entirely GHI world, however at the moment my only option is the Sytech display and I would like to be able to present it tomorrow.

Any help on this would as usual be very gratefully appreciated (And rewarded with some good old fashioned English beer if you wanted to make the trip !).

I can provide any other information if needed.

Many thanks,