I have a raspberry pi 3 that I powered with my computer directly and I can not use the GPIO pins because they don't send anything.
Do I really need a power supplier?
Yes, you definitely should use a "real" power supply, as mentioned here: Raspberry Pi, Powers supply
If you use any USB Ports or mobile phone chargers it can happen that some functions are not available, because of lack of power and/or voltage.
Here are the exact specs: FAQ - Power requirements
Quote from the FAQs:
2. CAN I POWER THE RASPBERRY PI FROM A USB HUB?
"It depends on the hub. Some hubs comply with the USB 2.0 Standard and only provide 500mA per port, which may not be enough to power your Raspberry Pi. Other hubs view the USB standards more like guidelines, and will provide as much power as you want from each port. Please also be aware that some hubs have been known to “backfeed” the Raspberry Pi. This means that the hubs will power the Raspberry Pi through its USB input cable, without the need for a separate micro-USB power cable, and bypass the voltage protection. If you are using a hub that “backfeeds” to the Raspberry Pi and the hub experiences a power surge, your Raspberry Pi could potentially be damaged."
Related
I am attempting to connect to a weight-measuring scale using the following communication line: Laptop -> USB to DB-9 Serial adapter -> Scale. The problem I'm experiencing is that my laptop recognizes the adapter as the device on the COM port, thus when I check the VID and PID of the device, it gives me the IDs for the cable and not the scale. Is there some way to find the information for the device on the other end?
I am coding in Python using the PySerial library, but any general answer would be helpful. The adapter I'm using is a USB to UART PL2303 from Prolific Technology Inc. My OS is Windows 10.
I have tried connecting scales from multiple different brands using a USB-to-Serial adapter, and I get the same result. I haven't been able to establish a connection with any of them, with all queries to the scales not being responded to. Two such scales are the Sartorius Entris and the Mettler Toledo Excellence Plus.
EDIT: Responses are saying that serial devices do not have a VID or PID. In that case, how can I tell if a serial device is a certain device from a specific manufacturer? I'm trying to do this so I can recognize when a scale is plugged in and not some other device, using a Python program to communicate with the scale.
Serial devices dont have VID/PID pair.
In "historic" times PCs have two ports - parallel and serial (also known as RS-232). Serial devices are PnP devices, so dont need driver and because this no need VID/PID pair.
What scales are you used?
If industrial, is very possible that are based on RS-485 standard.
for a simple project, I need a cheap wifi device, which can be used as Wifi repeater. I need also the possibility to include own functions (e.g. send own put/get requests to www from device itself).
I found a library to use esp32 as a nat-router (https://github.com/martin-ger/esp32_nat_router), but this seems to be a deep hack and it is too "advanced" for me.
Therefore, I looked for an alternative device.
Is it possible to use Raspberry Pi Pico W as wifi repeater using micropython?
E.g. Raspberry Pi Zero supports AP_STA mode, but I have to consider the costs.
Thank you.
What I did until now:
Research about esp32 as router, but no solution with Arduino or Micropython found. Tried to understand esp-idf code from above git, without a chance to extend with own www requests.
About Raspberry Pi Pico W, I found some examples only with single use in AP or STA mode.
I am trying to have a Raspberry Pi Zero emulate a Cisco USB console interface (non-FTDI version). At a high level this is actually not that difficult:
The g_serial driver running on the Pi can accept Cisco idvendor and idproduct parameters, so it will look roughly the same on a lsusb output
The Linux host uses the same driver, cdc_acm, to connect to the Pi and the Cisco Device
The one problem I am having is that the kernel device path is slightly different between the two.
Cisco: /sys/bus/usb/devices/1-1.4.2:1.0
Raspberry Pi: /sys/bus/usb/devices/1-1.4.2:2.0
The Cisco's device path ends in :1.0 and the Raspberry Pi's ends in :2.0. I know 1-1.4.2 comes from the USB hubs I am using on the host, but I do not know how the numbers after the : are assigned.
So my questions are:
how is the last number assigned in the devpath? does it come from the host or attached device?
is there anything I can do to the g_serial driver to make it better emulate the Cisco device and appear as :1.0
Note: I am not trying to fix this with a udev rule. My goal is to completely emulate the Cisco device with the Pi.
We have device with follow configuration:
Raspberry Pi 3 with Windows 10 IoT Core
4inch HDMI LCD with touch pad
Several external devices connected to 5V, GND and GPIO pins
All the scheme consumes 12V directly and 12V separately for other devices.
The problem is: Windows IoT some times not loading, presumably because of monitor power consuming.
Is it possible to configure programmatically or via Windows Device Portal to load HDMI after Windows IoT is loaded?
First, to determine if this issue caused by HDMI. You can check if this issue caused by HDMI via disconnect the HDMI to see if the system can boot up every time. (Use Windows 10 IoT Core Dashboard application to find its IP address. Via ping its ip address or device portal to see if the system has booted up.)
If the system can't boot up when you attach the HDMI pad, you can supply the power for HDMI pad separately. There is a power supply port, something like this:
i have Pi3 and i'm developing UWP to transfer data from/to Pi3 and another device (currently PC over UART)
but i can't get the right data, i'm using the Sample from Microsoft SerialSample but it didn't work, the data comes not right, i enforced the encoding in the App in both sides but no luck.
Link to the sample
You need check hardware compatibility list to see if your device is supported on Windows IoT core.
Also, and for serial sample here is a note to state the supported USB-to-TTL cables or modules:
NOTE: Only USB-to-TTL cables and modules with Silicon Labs chipsets are natively supported on MinnowBoard Max and Raspberry Pi2.
So, USB-Serial CH340 is not supported on Windows IoT core.
For doing self testing of the device, you can use the sample and do the following two tests :
First, shorten Tx and Rx of the USB-to-TTL cable to test it on PC.
Second, shorten Tx and Rx pins on Raspberry Pi to test its on-board UART.
You will receive what you have sent if the device works normally.