In rare cases, a serial device on a virtual machine might not have a serial.fileName property and the serial.autodetect property to be set to FALSE. As a result, the hostd service might repeatedly fail.
I mark it as solved but is not solved (still cracking/buzzing sound from speakers sometimes low level crack, sometimes high level crack from speakers) so install sof-firmware package: sudo pacman -S sof-firmware does not solve the issue. Change kernel to older LTS does not solve the issue too.My setting is:
cpu cool 7 0 5 serial crack
Not solved even if now the issue seems less prominent (crack sound is low now but still presented)But al least now sound quality seems better with pipewire (installed wireplumber too). Tried with media-session before install wireplumber but same issue.Pipewire is active i think
The Bus Pirate is accessed from a command line in a serial terminal. The Bus Pirate always starts in high impedance mode (Hi-Z), a safe mode with all outputs disabled. It's intended to protect any connected devices from conditions beyond their specifications. From there, a bus mode can be selected to use the Bus Pirate with a specific protocol.
The Bus Pirate is a slow serial port device intended for human-speed interaction. It was NEVER intended to do JTAG duties. Because it's open source, cheap, and versatile, the community hacked various JTAG features into it. They're great in a pinch, but no substitute for the real thing!
The Serial 7-Segment Display is an easy-to-use 4-digit display that is controlled using a serial interface. Instead of using up a dozen-or-so of your microcontroller's pins to control the LEDs, all you need is one. Using either a serial, I2C, or SPI interface, you can control all digits, decimal points, the colon, and the apostrophe.
Aside from the display itself, you'll need an Arduino (or one of its variants) to send the serial data. In the Arduino's stead, you could use an FTDI Basic, or any device capable of sending TTL serial data.
It'll be your choice to decide which of the three serial interfaces you'd like to use to connect to the display. Using a basic serial input, you'll only need to connect to the RX pin. I2C requires two pins, and SPI requires three.
The "Serial" in the Serial 7-Segment Displays is something of a generalization. Apt...but this display actually offers three different serial methods of interfacing: Serial UART, SPI and I2C. Each of these interfaces offer their own benefits and disadvantages. A big difference between each of the communication protocols is the number of pins each requires. They also each add their own level of complexity on the firmware end (though, with Arduino, libraries really simplify the task).
UART serial, or TTL serial, this may be the most basic serial communication method on the S7S. If you've played around with Arduino, you've probably used the hardware UART to relay information back to your computer via the Serial Monitor. Or set up a software serial port using the SoftwareSerial library. This form of serial communication is asynchronous, meaning the data is transmitted without any help from a parallel clock signal. This makes our job easier and harder. Easier in that we only need one wire (RX) to communicate with the display. Harder in that extra attention needs to be paid to making sure timing between bits is exact.
SPI is a synchronous serial communication method. It's kind of like taking the UART method above and adding a clock signal. This way we don't have to worry about what speed we send data (as long as it's not too fast), but we do require the use of two more pins.
SPI requires three wires for communication: data (SDI, that's "Serial Data In"), clock (SCK, "Serial Clock") and slave-select (SS, with a bar over it meaning it's active low), which is also known as chip select (CS). A couple caveat's on this serial method: the maximum clock speed for the S7S is 250kHz. And, data is clocked in on the rising edge of the clock (when it goes from 0V to 5V). It is also worth noting that the SPI connections on the master device, the Arduino in this case, are typically labeled MISO (Master In Slave Out) and MOSI (Master Out, Slave In). The MOSI line connects to SDI on the S7S, whereas the MISO line connects to the SDO line.
I2C exists somewhere between SPI and UART serial. This serial method requires only two pins -- SDA (serial data) and SCL (serial clock). Instead of using a chip select pin, like SPI, I2C devices are given unique 7-bit addresses. The I2C address of the S7S is configurable, but defaults to 0x71.
To interface other electronics to the display, you'll need to solder to some of the S7S's pins. Before you do any soldering, though, think on how you want to use the display. Do you plan on using one of the serial interfaces in particular? Maybe you only need to solder to the power pins, and the few pins which correspond to your preferred interface. Are you just prototyping with the display? Are you mounting it in an project enclosure? Your assembly method really depends on what your final goals for the display are.
If you intend to ever reprogram the display using an FTDI Basic, you might find it useful to solder some right-angle male headers into the serial programming header. This can be a bit tricky, as the display gets in the way. I solder my right-angler's on the curved side.
Just like its brother boards, the serial 7-segment shield can be controlled via SPI, I2C, and serial communication. You can choose which communication protocol works best for your specific application leaving the others open to interact with other pieces of hardware. It shares the same command set, and all the same example Arduino sketches work for it as well without needing to change a single line of code.
Before really delving into the examples, we should discuss what types of data should be sent to the display. As mentioned in the hardware section, the display provides for three serial modes of communication. In each serial mode, data is sent to the display one byte at-a-time. The byte (as bytes go) can be any value from 0 to 255. Data sent to the display will fall into one of three categories:
Serial is a great communication method if you want to minimize wires. If you're linking the S7S up to an Arduino, I'd really recommend you make use of the Software Serial library (included with Arduino) to communicate with the display, rather than hooking up to the hardware serial pins (D0, D1). This will make sure there's no bus contention, and, more importantly, it makes sure your display doesn't receive any data meant for solely your Arduino.
The sketch begins by cycling through a select few brightnesses, so you can see what the display looks at its dimmest and brightest. Following that, it turns into a stopwatch, making use of the s7s.print() function to send data to the display via the software serial library.
SPI is a useful communication method if you have more than one device to hook up on a single bus. It requires more wires than basic serial, but it's more dependable because it's a synchronous interface.
This example works a lot like the serial version. The s7s.print() functions from the previous example are replaced by SPI transfers. Take note that each time an SPI.transfer() occurs, it's blanketed by two digitalWrite()s to the SS pin. The SS pin must go LOW, to let the display know that usable data is incoming. Once SS goes back to HIGH, the display will know that data is no longer being sent to it.
If you are having issues uploading the most recent default firmware to the smaller (10mm) serial enabled 7-segment display via the Arduino IDE, try using the older version of the firmware in the GitHub v3.1 branch. This is the same firmware that is used in our production department.
If you believe that the smaller (10mm) 7-segment serial display has corrupt firmware, you could also reinstall the Arduino bootloader. You could use an AVR programmer to reflash the ATmega328P on the serial enabled 7-segment display.
If you have issues using the serial enabled 7-segment display where the LEDs flicker and display random numbers, it could be the way that you wrote your code. There was one case that tech support encountered where this happened after using a sequence of commands to clearing the screen, setting the mode, setting the brightness, and adjusting the cursor.
Testing with a 5V RedBoard, the major issues that seemed to be fixed was removing the clearDisplay() function and adding a delay between setting the brightness and your cursor position. The flickering may be due to clearing the screen and writing back on the screen in your main function. By avoiding the clear screen function every time my main function looped back, the serial enabled 7-segment displayed the counter better. By adding a 1ms delay, the serial enabled 7-segment stopped displaying random numbers and flickering. It's possible that the serial enabled 7-segment display does not have enough time to set the brightness for the entire display. Adding the delay probably helped in completing the function before moving onto the next command.
The alternative method for connecting the shield to the vehicle is to use the DB9 to OBD2 adaptor cable which plugs into the large serial port on the Sparkfun shield and the diagnostics port on the vehicle, it is recommended that you follow this tutorial using the diagnostic port first as you reduce the risk of harming the vehicle.
This is a long process but will allow you to easily correlate the data on a CAN network to the frame you are monitoring. In order to set a filter in the Arduino code to only show one frame though serial monitor, change the value -1 to the ID you are working on and != to ==, for the line if(message.id != -1) { in the code. 2ff7e9595c
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