is there any way to print rotated text to the screen?
I think I figured out the main problem.
It has nothing todo with the SPI bus ... It´s the 3,3V line.
Take a look at the picture. If you set the LCD to 80 (~33%) brightness then the PWM signal is extremly present on the 3,3v line ... And the MCP3204 don´t like that :-)
And this is a picture with 255 (100% on) brightness ...
No further explanation needed ...
today I spent some time getting my MCP3204 working. It´s a 4 channel ADC with an SPI Bus.
I connected the MCP like this:
#define SPI1_CLK 18 // D -> Clk -> Pin 11 #define SPI1_MISO 19 // Q -> D Out -> Pin 10 #define SPI1_MOSI 23 // -> D In -> Pin 9 #define SPI1_SS 16 // -> CS -> Pin 8
It´s working as expected as far as I don´t use any display stuff from the M5 Stack.
As soon as I ad the following to my code:
M5.begin(); // true, false, false); M5.Lcd.printf("TEST");
things getting wired. The readings of my MCP3204 are wrong.
I convert the AD values to temperature vales since I use some BBQ sensors. And the results are about 2 degrees wrong when adding the M5 Display.
Example: Reading temp without Display -> ~21° and with display ~23° or sometime ~17°
I can do some addition checks with the plain AD values to get a better understanding.
But anyway ... What´s wrong in using the SPI bus for a second device?
Are there any drawbacks i don´t know? Any issues?
Maybe someone has some explanation for this topic.
Some days ago I asked a similar question about powering the stack.
And until now there are no answers from the M5Stack employees. It's absolutely not understandable why those guys don't answer so important questions. And furthermore why there is no documentation about that power topic. :-(
Anyway ... Did you take a look into the IP5306 datasheet? Maybe you can find some answers there?
Sorry if I can help more.
what kind of sensors are you putting in it? flex sensors in the fingers?
Correct. I use 4 Flex Sensors in the Fingers. They 2,2" types from SparkFun.
I hope to get them working until sunday ...
I made a simple music glove before with flex sensors it was a lot of fun.
Did you have any photos? How did you sew the glove?
I found it really hard to get this glove as far as it is now. There are not really a lot of information in the web available ...
I just wanna show you my new invention ... the M5Stack Data Gloves :-)
The design based on the DIY arduimu gloves (which you can´t find any longer because the website is down :-( ).
Anyway. I redesigned some parts, learned sewing and now I`m close to build the sensor stuff.
I did some work on the code, too ...
Will keep you up to date if I did my first tests und if the code part is done.
So be patient :-)
You are aware that there are 2 battery connection on the M5?
1 is in the 2x15 connection, one is on the actual main pcb.
Yes I saw that. I think that both directly connected to the VBat connection, correct?!
5V connection on the 2x15 connector is the output from IP5306 VOUT pin
Well if there is no battery connected and no USB cable attached ... Why should this be a problem?
I would assume that the IP5306 has an internal protection for reverse current.
cutting traces on the PCB is always a bad idea I think ...
But connecting a 5V source to the 5V connection on the 2x15 connector should be ok, or not? If there is no battery connected we don need the IP5306?
you should not connect USB cable at the same time the external 5V is connected
That's correct but this is a compromise I can live with.