I am having an odd problem with my PIC16F88. I have an EEPROM connected thru I2C and it works flawlessly until I write to portb.bit6. From that point on, I start getting garbage from my EEPROM. I tried explicitly disabling Timer 1, which uses portb.6 for oscillator-out but that did not help. I tried cutting the trace from the PIC pin (pin 12) so that there is nothing physically connected to it and that did not help. My C code is simple, either portb.6 = 0 or portb.6 = 1. Either way, reading the EEPROM thru I2C fails forever more. The generated ASM code looks fine. The problem occurs on every board that I have tried it on, so it is not localized to one PCB. I am mystified. Any suggestions?
It turns out that it is necessary to write a zero bit to the SCL and SDA pins every time before writing to any bit in portb. FWIW, I was bit-banging rather than using the SSP peripheral of the PIC16F88 for the I2C communicaitons. Thanks to the people on the Yahoo group, Electronics_101, for figuring out this puzzle.
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somehow when i am running my code, it seems like one GPIO Port isn't being initialized, meanwhile if i am debugging, it is.
I am initializing two sensors:
struct MAX31856_t max31856_temperature_sensor_heater_1 = MAX31856_TPL( SPI_DEV_TPL( IO_PIN_TPL(
TEMP_SENSOR_0_CS_GPIO_Port, TEMP_SENSOR_0_CS_Pin), &spi1));
struct MAX31856_t max31856_temperature_sensor_heater_2 = MAX31856_TPL( SPI_DEV_TPL( IO_PIN_TPL(
TEMP_SENSOR_1_CS_GPIO_Port, TEMP_SENSOR_1_CS_Pin), &spi1));
Sensor Heater 1 is not getting any Information, Sensor Heater 2 is getting Informations. Now if i swap the Name of the Heaters:
struct MAX31856_t max31856_temperature_sensor_heater_2 = MAX31856_TPL( SPI_DEV_TPL( IO_PIN_TPL(
TEMP_SENSOR_0_CS_GPIO_Port, TEMP_SENSOR_0_CS_Pin), &spi1));
struct MAX31856_t max31856_temperature_sensor_heater_1 = MAX31856_TPL( SPI_DEV_TPL( IO_PIN_TPL(TEMP_SENSOR_1_CS_GPIO_Port, TEMP_SENSOR_1_CS_Pin), &spi1));
and run the code in the debugger, Sensor Heater 1 and 2 are getting Informations.
How can this happen? I was thinking about a timing problem, but since it is working in the debugger, i don't really know what to do.
Provided that you are debugging and/or running the same binary. Debugging is mostly the same as running except if you halt the processor (es breakpoints).
In that case...
some peripherals could continue to run or be halted togheder with the cpu, the behaviour is some cases can be configured. (timers, watchdog...)
some interrupts can be lost.
some hardware buffers can overflow and data can be lost (if you don't use any flow control in your IO)
How do you run the code in debug mode? Do you have breakpoints somewhere?
You (OP) are right about it being most likely a timing problem, and probably related to physical SPI transmission. Because your line of code to send/receive something over SPI has already executed in the MCU, but physically the bits and bytes are still being transmitted on the line, while MCU is already calling the next SPI function, so one of the transmissions will fail. Try adding some delay after SPI transmission code. If things work after that, then it's the timing of SPI peripheral, and you need to add a check that there is no SPI transmission already in place before you call a functions to send/receive something.
You can do while(transmission) (pseudocode, replace with actual check if SPI transmission is going on) to wait until the previous transmission ends to call the next one.
I just installed the latest version of LIRC(0.10.1-5.2) on my Raspberry Pi 3, running Raspbian on Debian Buster.
I am trying to get my Pi to take input from an IR remote using lirc.
I have made the necessary changes to these files :
/etc/lirc/lirc_options.conf
driver = default
device = /dev/lirc0
/boot/config.txt
dtoverlay=gpio-ir,gpio_in_pin=18,gpio_out_pin=17,gpio_in_pull=up
//I set mine on up on GPIO pins 17 and 18 instead of 22 and 23
I have checked and cross-checked my circuit. Everything looks okay.
The challenge I'm facing right now is when I test my IR receiver using the following command,
mode2 -d /dev/lirc0
Nothing happens. There's no output at all. No pulses recorded.
Has anyone else experienced this issue?
Any help would be much appreciated.
After spending a great amount of time, trying to figure out how to solve this issue, I was finally able to resolve it.
So hopefully my answer will help someone else.
First things first, it's important to note that infrared device has changed from lirc-rpi to gpio-ir
Although, I already had this change in my /boot/config.txt
file,like below:
dtoverlay=gpio-ir,gpio_in_pin=18,gpio_out_pin=17,gpio_in_pull=up
// in stead of dtoverlay=lirc-rpi
I just thought it was important to point out.
Since I am trying to get my Pi to take input from an IR remote using lirc, I decided to first test my IR sensor separately, to make sure it works.
To do that, I connected up the sensor like so:
Pin 1 is the output so we wire this to a visible LED and resistor
Pin 2 is ground
Pin 3 is VCC, connect to 3v3
You can find more detailed step by step instructions from this tutorial here which also shows how to wire up your circuit as seen below.
During this test, my LED lit up each time I pointed a remote at the receiver, which gave me hope that it was working just fine.
The next step was to test the IR receiver on my raspberry pi, which is the challenge I had in the beginning.
I re-wired my circuit, this time:
Pin 1 is DATA, goes to RPi pin 12 (GPIO 18)
Pin 2 is GND, goes to RPI pin 6 (GROUND)
Pin 3 is POWER, goes RPi pin 1 (3v3)
Then I ran this command sudo /etc/init.d/lirc stop to make sure that service wasn't running.
I then ran the initial command mode2 -d /dev/lirc0 and now pressed random buttons from my remote at the receiver and violá! I could see some pulses on the screen with each button press now.
Like you I managed to get all the way to receiving pulses/data on the RPI 3, seem to have a problem with the output.
I have the USB strip light and my RPI with the IRC receiver, this is so I can monitor what data captured corresponds with the button pressed on the remote keypad. Works just fine.
However? If I push the ON button - I get data, if I push the ON button again I get another set of data. The two set of data dont match? , in both cases mode2 or mode2 -r.
I get the feeling I'm missing a method to decode the output, I've noticed there's a huge amount of companies and they all have distinct code sets.
Here is one thread that exactly matches what I have (24-Key IR remote).
http://woodsgood.ca/projects/2015/02/13/rgb-led-strip-controllers-ir-codes/
However I dont see the same set codes ???
Try to change the device to mode2 -d /dev/lirc1
I also faced this.
Currently i am trying to get the STM32F405 to jump to bootloader from application code without the use of the boot0 and boot1 pins.
I did already try multiple things to get that done but it always ended with the the firmware jumping to the bootloader (at least it seems like it) and after approximate 18 seconds the firmware restarts (no Watchdog or similar things that could wake the chip up again are used as far as i know).
During those 18 seconds if i try to update the firmware the bootloader doesn't get found.
I tested things like:
1. (STM32F4 Jump to Bootloader via SoftReset and without BOOT0 and BOOT1 Pin)
Set a value in SRAM
Restart the STM32F405 with NVIC_SystemReset() to get the STM32F405 to close reset condition
Check for value in SRAM ( if it's set do the following )
Move stackpointer to bootloader address
Jump to bootloader address + 4 (0x1FFF0000 + 4)
2.
During runtime call function JumpToBootloader()
Within that function disable interupts, reset SysTick, reset SYSCLK, call RCC_DeInit()
Move stackpointer to bootlader address
Jump to bootloader address + 4 (0x1FFF0000 + 4)
One approach i found but couldn't test yet was to do basically what i discribed in try 1. but using assembler code within the STM32F4xx startup file.
The problem here is that the tutorial i found uses the KEIL assembler syntax which i cant use because i use the Atollic TrueSTUDIO and i have not enough knowlege about assembler to change the KEIL syntax to standard assembler syntax.
The thing that confuses me the most is that in an other project i use an STM32F3xx (cant remeber the correct number) and i do basically the same thing as in try 2. but with the the bootloader address of the STM32F3xx (0x1FFFD800) and it works perfectly fine and i can update the firmware via USB.
So the questions i have:
What could i try next to get the bootloader running?
What could be the cause in my current situation for the firmware to restart after X seconds?
A few days ago i found the cause of the problem i had.
Within the "system_stm32f4xx.c" the I2S clock got configurated and in my project that clocks doesnt get used.
Im not 100% sure why, but after removing this block of code everything works perfectly fine.
(sorry for late answer, kind of forgot about the post :D)
I have been working with ATmega128 and other such series for about 2 years and used a UART library for serial transmission. I am pretty sure the library is correct because I have used it hundreds of times but from the past few months I cannot do UART on my ATmega128. I am sure that my hardware is correct, I am sure of my code and to add to it, the same hex file runs good in other two ATmega boards but not in other boards.
PORTs are giving 5V output when all pins coded to give output.
Statements execute before any UART function occurs and after that it stops (does nothing, no UART, not even statements after UART)
I tried copy pasting UART code completely in main.c and it worked then.
Please help! I have no idea what is going on.
Well, after a lot of tussle, I finally found the problem and solved it. When I checked the fuse bits of the other microcontroller (the working one), I found Extended Fuse bits different from the not working microcontroller. I changed the Extended Fuse bits to 0xFF and problem solved.
I am trying to use the expansion header to control a couple motors and auxiliary task mechanism. For this I am using the appropriate pins as GPIO and merely attempting to send high or low signals as needed by the robot. (For instance, I might need the robot to move forward and so I'd send high signals on both sets of pins, whereas if I needed the robot to turn I'd send a high signal to one pin and a low to the other.)
However, the problem is that the pins will only stay high! I've followed the conventions for sysfs just via the terminal, and, although I'm able to set the "values", "active_lows", etc. to 0 or 1, I can't actually get the pins to send 0V. After checking the beagle.h file I used for u-boot it looks like the multiplexer mode is configured correctly. This is also reflected when I get the info from sys/class/gpio/gpio%/% and sys/kernel/debug/gpio. Furthermore I don't get any errors or indication from anywhere that there is something wrong...it just doesn't work!
What should I do? For the first time in my life I have seemingly exhausted the internet...
details:
Beagleboard xm rev c1
ubuntu 12.04
kernel 3.6.8-x4
Im pretty new to the beagle board and I have recently been trying to configure the GPIO pins on my classic beagleboard c4, which i believe should be fairly similar.
Half of my GPIO pins seemed to work fine and the other half seemed to remain high or low no matter what i did. Even though they were configured the same way as the working pins in /sys/class/gpio/
have you tried to use other gpio pins?
I ended up following http://labs.isee.biz/index.php/Mux_instructions
to configure the mux to 4 and now i can control the pins that were not working.
I basically used the command:
sudo echo 0x004 > /sys/kernel/debug/omap_mux/(mux 0 name)
where (mux 0 name) was the name of the subsystem for the mux 0 setting for the gpio pin you wish to configure
ie. for gpio 183 on beagleboard c4
sudo echo 0x004 > /sys/kernel/debug/omap_mux/i2c2_sda
Though I had to change permissions to modify these files
As I said I am pretty new to the beagleboard and ubuntu but this worked for me so I thought I would share it with you, I hope it is of some help.
Regards;
Paul;
It seems that the beagleboard expansion pins are numbered in alternating fashion, as clearly and professionally depicted here.
Thanks to everyone for your help. I now know way more than I should about GPIO on OMAP systems (and so do you). Good luck on finals/life!**
tl;dr I'm an idiot!