I'm having trouble with i2c communication. In my i2c bus, i have 4 boards (STM32L4 Sensortiles) and sometimes one of them blocks the bus and the others stop communicating consequently. When I reset that one that blocks the bus, all boards starting working again.
In my debugs, this bug happened when HAL_I2C_GetState(&hi2c3) returns HAL_I2C_STATE_BUSY_RX, even my others i2c functions HAL_I2C_Slave_Receive_IT and HAL_I2C_Slave_Transmit_IT returns HAL_OK:
Any ideas what Im doing wrong? Thanks.
Using libraries like HAL leads to problems like this one. Why?
HAL users feel free from knowing your hardware as magic library will do everything for you.
HAL users usually do not know how the peripheral works and how to debug it.
HAL users do not bother to go through the magic HAL function to see what the problem is.
Posting some images form debugger will not help.
What you need to do:
Get even the cheapest logic analyzer (there are $10 on ebay) and record the communication. See if the slave keeps the clock or data line low. If yes toggle the clock pin 9 times to unblock the line
If nothing helps reset the I2C peripheral using RCC register (it has to be implemented on all connected boards).
Related
I am trying to make some custom firmware for a MIDI controller (AKAI LPD8).
There is an STM32F102R8T6 chip in the unit.
I am trying to reach it with a programmer to wipe it, but it seems to not be responsive.
Some information and thing I have tried:
The firmware that came with the unit works, so the chip is not broken
Removed the components connected to the programming pins (PA9-PA10 and PA13-PA14)
I am able to pull BOOT0 high and have it not run the main program, but I am however not able to get a life sign using either an ST-Link2(clone) connected to PA13/14, nor a USB to serial adapter connected to PA9/PA10, so I am not sure what mode it is in
The connection has been checked, and RX-TX etc is the correct way around (but also for the sake of trying it all, I reversed the connections as well...).
Tried both the STM32CubeProgrammer and stm32flash, but none connects.
I am actually not sure if AKAI have locked the chip in such a way that you cannot even do a full chip erase and use the chip for something new? The NRST pin is strangely not doing anything to the running of the firmware either when I try to pull it low.
Is there a way to reprogram these chips when they come off of a commercial product, or are they permanently locked?
Any solution/tips?
Many of the STM32 parts have "proprietary code read-out protection" (google PCROP) which but you might be lucky and they haven't enabled it in the option bytes. Read the documentation for that and the bootloader documentation and get a good idea of what you expect it to do if it is enabled and if it isn't.
If you have a scope, try watching the SWD/JTAG pins to see if there is any response from the device. (If you aren't even sure if it is in reset then scope the crystal if there is one).
If you haven't got a scope, you might be able to to verify what it is doing by seeing if it sets the pins and pull-resistors to how they would be expected to be in the bootloader mode, eg: UART TX should be high if it is enabled, even it it isn't transmitting anything. Put a strong pull-down (~1k) on there and see if it still reads high.
After hours of trying different ways of making it work (also tried the alternate mapping of the UART port), and probed the TX pin as suggested by Tom V to no avail, I have given up working on that specific chip and ordered an upgrade from the STM32F4 family instead to replace it with. A lot more power and useful peripherals.
A bit of a non-answer to the specific question. Frustrating to not have found out what was wrong (chip or approach) but being mindful of the sunk cost fallacy, I think it was best to just replace the chip with a fresh one and start development from there.
I have been having an issue in my project with LWIP. I am using a ST32F4 MCU and running with no OS. The network seems to run fine, the protocols all work, but then (usually a day or two later) the stack just stops running. It seems to happen when trying to make a new connection, but I can't confirm that because I haven't been able to locate what is causing it in the code.
Has anyone else come across this issue? I think it may be the same as this guy.
Do you call any LwIP functions from any interrupt-handlers, like UART etc?
How do you feed packets in/out of LwIP? Directly via interrupt handlers, or do you push them in from your "main-loop" ?
Lock-ups can also be signs of double free, or use-after-free of pbufs.
I also experiences that one project was unstable with wierd random locks-ups when running at the top-rated frequency of the STM32. If I clocked my STM32 at 100MHz instead of 120MHz, all my problems went away....
I have started a threat to read/write SPI flash memory for s3c2440 Microcontroller. All register setting are done properly and flash memory read/write functionality working perfectly.
S3c2440(ARM9) spi_read_write Flash Memory
Now, I want to do the same thing with "S3C2451 16/32-Bit RISC Microprocessor"
Then what will be the register configuration for "S3C2451" to achieve the same?
I have studied and compared both the datasheet "S3C2440A" and "S3C2451" and found that so many register are different. I have also notice that in datasheet says "S3C2440A" is "32-BIT CMOS MICROCONTROLLER" and "S3C2451
" is "16/32-Bit RISC Microprocessor". So, Is it not the same architecture wise?
So, please guide me to achieve the same.
UPDATE
I got a link of nearly similar code of s3c6410. But at a glance I am not able
to understand what will be the minimum register configuration for
configuring SPI channel 0 with 5 MHz clock output.
http://read.pudn.com/downloads131/sourcecode/embed/558985/Components/con...
I want to configure it for s3c2451 Processor. Please guide me .....
Thanks in advance.
I am working on a university project in which i need to interface pic18f4550 with i2c EEPROM.
I implemented the following circuit using proteus simulator. The following in my connections
when I implemented the interfacing on real, I faced a problem when the PIC reads from the eeprom. it is suspended and so I was not able to see if the reading operation was performed correctly.
What could be the problem?
You do need to make sure you are following the I2C protocol for reading an EEPROM, and that is best served with a state machine on a PIC.
Try sequencing through the following actions, making sure your flags are set correctly:
Start condition
Write to the EEPROM with the address to which you want to read.
Repeated Start condition.
Read from the EEPROM as many bytes as required (keep in mind that the EEPROM is paged, and you will roll over if you go past a page boundary.)
Stop condition
I'm not an Atmega pro by any means whatsoever. In fact, never worked with them. I'm trying to add an external eeprom using i2c interface to a device that uses an Atmega64 controller. From the datasheet, I see that pins 25 and 26 are labeled PD0/PD1 and are the SCL/SDA for i2c. That's fine and dandy. So then I go to the board and start tracing. I see that those go to a rocker switch with some simple circuitry that I haven't had a good look at yet, but I assumed it was something i2c compatible. But then what dawned on me was that this device has two such rockers so I expected to trace the other rocker back to the same two pins (since i2c is a bus that can have multiple slaves). Instead, they traced back to the two adjacent pins 27 and 28 labeled PD2/PD3 and RXD1/TXD1. Well, now that confused me.
I expected that I could add the memory in parallel on the SCL/SDA lines, but does what I now figure that what I discovered either means:
SCL/SDA is interchangeable with RXD1/RXD2 or
I'm confused on how SCL/SDA works and its not a bus or it can be used as a simple input?
Sadly, I'm not really sure what I'm asking. Can someone shed some light on this? Should I still be able to add the memory to SCL/SDA or probably not?
Thanks.
Steve
Nevermind, I found the answer. Its BOTH a bus and a simple input... either one or the other. In this case, its being used as an input so I can't also use it as a bus. Darn. Oh well.