STM32L476 LCD configuration and display - stm32

I have configured my board using STM Cube, including LCD pins. Everything is in green, so i supose it's good. Now i want to display some data using the code below. But no matter what i put in "Data" LCD display no-sense things.
HAL_LCD_Init(&hlcd);
uint32_t counter = 0;
for(counter = LCD_RAM_REGISTER0; counter <= LCD_RAM_REGISTER15; counter++)
{
HAL_LCD_Write(&hlcd,counter,RegMask,Data);
}
HAL_LCD_UpdateDisplayRequest(&hlcd);
And what should be putted in RegMask? It seems to doesn't change anything.

I have found out that Hal lcd libraries is not for the lcd on the board. I have tried to use BSP libraries included to the demonstartion source (you can find it in stm cube repository). So if you will have the same problem as me - use BSP. It is very easy to use (translates direclty from string).

Related

Can we re-route the DAC output to some other Pins other than PA4 and PA5 in STM32?

I am working with STM32H743, and I want to use Pin no. 89 as DAC output. Is there any register setting where I can change PA4 to PG4(89).
I tried replacing PA4 to PG4 in a working example code, but the output still comes on PA4.
I don't know which STM32F7 you are using exactly so I could not lock at the Reference Manual, but I guess it is the same as on STM32F4 devices:
The answer is quite simple:
NO, you could not reroute the DAC pins.
(A look ad a randomly chosen F7 datasheet also shows only one pin for the DACs)
I simply guess it is not possible to route the output signal through a multiplexer without generating to much interference.
According to the H753 datasheet (can't find a specific one for H743), there are two DAC channels, PA4 is DAC1_OUT1 and PA5 is DAC1_OUT2. It does not appear to be changeable.

What am I missing? Send data from Matlab to Arduino to Micro SD

First off. This is not in any way a class assignment. This is my own personal work and research. I just want to get that out of the way.
I am learning how to use Matlab with various Arduino projects. I am a seasoned Matlab user but I am fairly new to the entire Arduino space.
I am trying to send some numerical data from Matlab (via a GUI) to my Arduino Uno and have the Arduino write it to my micro SC card. This is a temporary step to my larger project. However, there is no need to go into those specifics as they are outside of the scope of my issues.
I am fairly confident that the Matlab code works and the Arduino code is slightly modified from another project I did where I wrote and read random numbers from my micro SD card.
However, as I run the Matlab code, the Arduino blinks as if it is receiving the data but after I check the micro SD card it remains blank.
I am confident that my Arduino is wired correctly to my micro SD card adapter since this remains the same from my prior project.
Therefore, I am sure I am missing something trivial to get it to work.
I have researched several websites on the subject and their method and mine seem to align very well.
I am fairly certain the problem is in the conditional statement:
if (Serial.available() > 0) {
As you will see.
The Matlab code is below:
arduinoCom = serial('COM3', 'BaudRate', 115200);
sendData = 5;
fopen(arduinoCom);
fprintf(arduinoCom,'%i',sendData); %this will send 5 to the arduino
fclose(arduinoCom);
delete(arduinoCom);
The Arduino code is as follows:
#include <SD.h> // load SD library
int chipSelect = 4; // Chip select pin for the MicroSD Card Adapter
int incomingByte = 0; // for incoming serial data.
File SDF; // Serial data received is saved here.
void setup() {
Serial.begin(115200); // start serial connection to print out debug messages and data
pinMode(chipSelect, OUTPUT); // chip select pin must be set to OUTPUT mode
while (!Serial) {
}
}
void loop() {
// Open file, Write data, Close file only when you receive data
if (Serial.available() > 0) {
incomingByte = Serial.read();
SDF = SD.open("SerialDataFile.txt", FILE_WRITE); // open "SerialDataFile.txt" to write data
SDF.println(incomingByte, DEC); // write ASCII-encoded decimal number to file
SDF.close(); // close file
}
}
The expected result would be a file "SerialDataFile.txt" stored on my micro SD card with the value 5.
Thank you for your help!

LPUART1 not working on STM32L476 (based on VisualGDB)

Hi I am developed a board based on the Discovery L476 board (STM32L476VGT6) using MBED and after porting it to VisualGDB everything works great. The only thing that doesn't work is LPUART1. I hooked it to PB10(LPUART1_RX), PB11(LPUART1_TX) but whenever I declare the port in my code and download it, the program hangs and doesn't even start:
Serial RS232(PB_11, PB_10);
If I remove this line, the code works great (but I can't use this port)
I changed the pin definitions in PeripheralPins.c so PB10 and PB11 will function as the LPUART TX and RX pins: (I added the lines)
const PinMap PinMap_UART_RX[] = { {PB_10, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)},
//
const PinMap PinMap_UART_TX[] = { {PB_11, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)},
but it still doesn't work. Any ideas?
See https://github.com/ARMmbed/mbed-os/issues/5389, the baud rate needs to be set at [sys_clk / 4096 ... sys_clk / 3]. Sys clock on this device is running at 80MHz. You could fix it in the HAL for this board until a real fix is deployed.

max732x.c I2C IO Expander + GPIO Keys w/ Linux Device Tree not working

I'm working with a Freescale MX6 and a 3.10.31 Freescale modified kernel. I have a Maxim MAX7325 used as an IO expander, which has pushbuttons attached to P0-P2. The interrupt line from the 7325 is attached to the GPIO_3 pad (which I believe is GPIO1_3...)
I set up the 7325 and gpio-keys in the device tree like this:
max7325_reset: max7325-reset {
compatible = "gpio-reset";
reset-gpios = <&gpio5 16 GPIO_ACTIVE_LOW>;
reset-delay-us = <1>;
#reset-cells = <0>;
};
gpio-keys {
compatible = "gpio-keys";
sw2 {
gpios = <&max7325 2 GPIO_ACTIVE_LOW>;
linux,code = <30>; //a
gpio-key,wakeup;
};
};
and
&i2c1 {
clock-frequency = <100000>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_i2c1_2>;
status = "okay";
max7325: gpio#68 {
compatible = "maxim,max7325";
reg = <0x68>;
gpio-controller;
#gpio-cells = <2>;
resets = <&max7325_reset>;
gpios = <&gpio1 3 GPIO_ACTIVE_LOW>;
interrupt-parent = <&gpio1>;
interrupts = <3 2>;
};
};
What appears to happen is when probe for the MAX7325 driver is called, client->dev.platform_data is NULL. Because of this, when max732x_irq_setup is called later, it doesn't set up the chip->gpio_chip.to_irq pointer to point at max732x_gpio_to_irq function (presumably because it doesn't have the right info for this to work.) Later, when gpio_keys
tries to config the first input, it fails when it tries to set up the interrupt and none of the other keys get set up.
gpio-keys gpio-keys.20: Unable to get irq number for GPIO 242, error -6
I did determine using the /sys interface that P0 maps to GPIO 240, so yeah, GPIO 242 is the sw2 GPIO-KEY I was trying to set up.
I'm wondering, does this driver not work with a device tree? I don't see it trying to get any device tree properties, but other IO expander drivers I looked at didn't either, so I thought maybe the I2C core is reading the device tree and supposed to fill in the platform_data from there somehow before it calls the driver's probe function (?)
I'm fairly new at this, so any help would be appreciated. =) I did read a few of the Device Tree docs online, but I'm thinking this is something fairly specific that I'm not doing correctly, which they don't cover... (?)
I do have CONFIG_GPIO_MAX732X_IRQ configured in the kernel... and I did at one point try setting the interrupt-controller property for the max7325 I2c1 node, but I wasn't sure that was needed (?)
MAX732x device tree support
Driver you are using won't work with data from device tree. I have added device tree support to this driver and sent it to kernel mailing lists for review, but they are not merged yet. See this thread (total 4 patches):
You can either apply those patches to your branch or wait for them to get into upstream kernel and then cherry-pick them from there (into your branch).
Bindings documentation (see patches above) shows how to create device tree declaration for MAX732x. In your case it may look like this:
&i2c1 {
expander: max7325#68 {
compatible = "maxim,max7325";
reg = <0x68>;
gpio-controller;
#gpio-cells = <2>;
interrupt-controller;
#interrupt-cells = <2>;
interrupt-parent = <&gpio1>;
interrupts = <3 2>;
};
};
Another way for you to use this driver (without patches above) is to specify platform data in board file for your board. I believe it should be one of next files:
arch/arm/mach-imx/mach-imx6q.c
arch/arm/mach-imx/mach-imx6sl.c
arch/arm/mach-imx/mach-imx6sx.c
You can find an example how to do so here: arch/arm/mach-pxa/littleton.c, line 394.
But it may be not reliable way: I tried to do so and had some issues with i2c buses numbers (didn't look too much in that way though). It also looks bad to scatter devices' definitions between board file and dts file. So I strongly recommend you to use patches above.
Answers to questions
What appears to happen is when probe for the MAX7325 driver is called, client->dev.platform_data is NULL.
It happens because driver was binded with device declaration from device tree file rather than from board file. In that case driver should use client->dev.of_node instead of client->dev.platform_data. Just see how it's done in my patch above.
You can read more about how binding/matching/instantiating happens in kernel documentation here:
Documentation/i2c/instantiating-devices
Documentation/devicetree/usage-model.txt
I thought maybe the I2C core is reading the device tree and supposed to fill in the platform_data from there somehow before it calls the driver's probe function (?)
No. When binding is happening, client->irq being automatically populated in I2C core (before driver's probe function being called). Properties like gpio_base and irq_base -- you don't need them in case when data came from device tree.
I did at one point try setting the interrupt-controller property for the max7325 I2c1 node, but I wasn't sure that was needed (?)
MAX7325 issues interrupt to your SoC when it detects changes on input lines (more specifically, on open-drain I/O ports configured as inputs).
So if you want your driver to generate separate interrupts for each input I/O line (so that other drivers can consume them), you should specify "interrupt-controller" and "#interrupt-cells" properties. But for this you need all patches mentioned above to be applied.
Patches status
Now all mentioned patches were merged into upstream kernel (v4.0 and later):
gpio: max732x: Add device tree support
gpio: max732x: Rewrite IRQ code to use irq_domain API
gpio: max732x: Fix possible deadlock
gpio: max732x: Add DT binding documentation
Also notice that there are some new patches were made on top of my patches. You can watch them here.

Is there a way for SDL2 to render to a GPIO screen raspberry pi

I'm trying to write a graphical program using SDL2 to output to a 2.3 inch screen connected through the GPIO pins on the raspberry pi. I can't seem to get the monitor to be recognized by SDL.
I read somewhere that these gpio monitors aren't recognized as regular monitors. Is this true? And is there any way to get SDL to use it?
I appreciate any help anyone has!
My code if anyone is interested:
struct {
SDL_Rect bounds;
SDL_Window* window;
} window_data;
int main(int argc, char** argv) {
int num_displays = SDL_GetNumVideoDisplays();
printf("\n\n\t%s\n\n", num_displays);
struct window_data screens[num_displays];
int i;
for (i = 0; i < num_displays; i++) {
SDL_GetDisplayBounds(i, &(screens[i].bounds));
screens[i].window =
SDL_CreateWindow("Display " + i, screens[i].bounds.x,
screens[i].bounds.y, screens[i].bounds.w,
screens[i].bounds.h, SDL_WINOW_FULLSCREEN);
}
}
Edit: It looks like the little display is seen as a framebuffer device in /dev/fb1. I can write to it though static comes out. (fb0 being my HDMI display). Is my code correct for cycling through the framebuffer devices? When I use this method, it doesn't seem to detect the HDMI display either.
Edit2: Would something like DirectFB assist me here for providing an interface for the framebuffer devices? Am I on the right track with that idea?
Edit: DirectFB is in alpha on the pi and is not recommended I learned. My goal is to draw image files and a bit of text on the screen and be able to choose the image's rotation. At this point I'm open to any way I can realistically achieve this.