Grrrr, It start bad !
A lot of question
I need a Nexion touch Screen ( with finger not with pen)
It is available in 4.3" or in 5"?
Well, now I use my own dev card with Atmel M644 or M1284.
if I understand well
The nextion editor it used to develop page/screen with push button, radio button and so one.. then the HMI and/or TFT files are dowloaded to a SD card ? Right?
Then My Atmega send and receive data to the nexion via Ascii char and the rx tx wires ? right ?
the baud rate is adjustable
I would like to know also what kind of RTC is used ?
I download the last update version of Nexion editor, when I download the sample for 5" or 4.3" the debug said it is a old version so I cant use it ?
Many thanks for your answers
I assume Nexion is a good product , and when I will started I will happy. but I need some good help to start !
Compiled HMI project is a TFT file, uploaded to Nextion device microSD or TTL serial.
Resistive touch does accept finger, but not like capacitive
Capacitive dates are not yet known - size 7.0" first, 4.3" next (was June~ish)
Nextion Instruction Set explains which baudrates are supported
RTC used is only in Enhanced Series, and is the Real Time Clock kind.
Sample file is v0.32 to allow device to be selected - must save before build process.
Nextion is only a good product when being used as HMI (Human Machine Interface)
- if and only if, you wish for reasonably priced device compared to $1000 Samsung
- if and only if, you wish for text-based human understandable command set
- if and only if, you want to save time in GUI development, process MCU side
- if and only if such project isn't trying to be a cell phone or desktop.
- if and only if goal to reduce wire count down to two (serial is slower)
but Nextion compensates for with fast graphic processing Nextion side.
Nextion Quick Start Guide is available from Help menuitem of Help Menu
- as is most important documents (datasheets) and good threads.
- Nextion Instruction Set is key to success
Nextion Questions this forum
- MCU language, compiler, programming, electronics - not this forum
Button on canvas has two touch events - Press/Release
- in each desired event to inform MCU check Send Component ID
Nextion will send 0x65 Return Data as per Nextion Instruction Set
Handle in MCU side code
With such quick and simple - HMI designs are made rapidly, hours not weeks
More advanced topics will require more time and user effort.
Hope this is helpful
OpenSource Fishtank project
- entire HMI is made with "checking" Send Component ID
- the MCU responds as required to incoming 0x65 Return Data
- Graphic and Fonts are stored Nextion side
as such swapping on pic "on" for another pic "off" is fast
MCU might sent p0.pic=3ÿÿÿ for on and p0.pic=2ÿÿÿ for off
- Changing HMI pages
MCU might send page 2ÿÿÿ to switch to page 2
- Update a temperature (integer not float)
MCU might send n0.val=27ÿÿÿ
slightly more advanced float with degree and scale
MCU might send to text component t0.txt="27°C"ÿÿÿ
Update to synchronize time
Favourite Graphic program is useful indeed.
Some layouts are extremely quick
pic page of all components in on state
pic page of all components in off state
then use a crop image to toggle area between these two pics.
Most code will normally be MCU side
- but we also discover that Nextion side Logic is very capable (advanced)
Nextion side Function in very little time
- tweaking to make it pretty... well lots of time can be invested in
- Transfering MCU logic to Nextion Logic
is at times useful, but not needed for project to be functional
much time can be invested into having Nextion be more than screen