Serial comms for a 4D display

[PeterMcLeod]

I'm bogged down with what should be a simple task. I want to design a CPU for a couple of machines. It has to collect data from a 4D touch screen and set machine variables. The 4D display uses a simple serial input using Tx and Rx lines only. To ask an object on the screen to change it's status I have to send 6 bytes. I then read one byte return.
This has had me stuck for months now! I originally tried an ARM processor using my Mikropascal for ARM registered compiler. This has been totally unsuccessful even with a lot of support from both 4D and MikroElectronica.
On advise I changed from ARM to AVR and purchased a "Ready for xmega" board. I fortunately have a MikroPascal for AVR registered compiler. In both the ARM and AVR compilers the library functions are very similar so it was not difficult to write the code, I used a single object on the screen and told it to set to mid-scale.

I have trawled the internet but in general the examples given for UART communications either send one byte or text. (I need to send 6 bytes ie 0x01, 0x10, 0x00, 0x00, 0x32, 0x23)
Why is this soooo difficult?
Please don't suggest 4D clicker I've tried that, it's too complicated for this project (and me)!!

[jovana.medakovic]

Hello,

If you want to send 6 bytes through the UART communication, you can use for loop which will iterate 6 times and you will send byte by byte.
I believe that I sent you the source code of our 4D display click board, so you can look at our c4d_writeObj function.

Kind regards,
Jovana

[PeterMcLeod]

Thank you Jovana
Yes I understand I can use a FOR loop and it was part of my test program for the ARM processor. I have tried this with the AVR processor and it is not where the problem lies. You mentioned the source code for the click board but I did not get the attachment. Could you send it again please?
You mentioned the ".. c4d_writeObj function..", can I use this in isolation if I have the library added?
Thanks again
Peter

[jovana.medakovic]

Hi,

In the attachment, you can find the source code.
Yes, you can use this function in isolation, only you have to rename it.

Kind regards,
Jovana