Linux tip: How to reset device connected to USB port

Sometimes devices connected to USB ports need to be re-set. It’s not unusual GSM modems and WiFi dongles to freeze and the only way to bring them back to life is to remove and re-attach.

OLinuXino USB ports has power switches and current limiters which can be controller by Linux drivers.

After some experimenting we found that it’s not so easy actually to do it with the standard file system and shell.

A friend suggested to try this code. It worked very well, so here is how to use it. First you need to download and compile it, then to make it executable:

$ mkdir usbreset
$ cd usbreset
$ wget $ https://raw.githubusercontent.com/jkulesza/usbreset/master/usbreset.c
$ cc usbreset.c -o usbreset
$ chmod +x usbreset

Then you need to see where your USB device is. In our case I connected MOD-WIFI-R5370 WiFi USB dongle:

$ lsusb

you will see something like:

Bus 002 Device 039: ID 148f:5370 Ralink Technology, Corp. RT5370 Wireless Adapter

to reset this device use the command:

./usbreset /dev/bus/usb/002/039

The device USB port will be power off for a second then power on again.

All above is tested and work with official Olimex Linux images from images.olimex.com, but should work on other Linux distributions too.

New Open Source Hardware board ESP-PROG allow you to program any Espressif device and can be used as general purpose USB-Serial converter

Created with GIMP

ESP-PROG is USB to Serial converter but beside the Serial TX and RX signals it also can power the target with +5V up to 0.5A or 3.3V up to 0.5A and have two additional signals which make programming automatic RESET (EN) and BOOT enable.

ESP-PROG-C includes all necessary cables for the ISP programming – 7 pcs jumper wires female to female and 6 pin ICSP cable.

ESP-PROG is based on CH340T IC and has drivers for Linux, Windows, MACOS, Android with up to 2 Mbps speed.

New useful parts for OLinuXino OSHW Linux computers, soldering tool and new components in stock

USB-RS485-wiring

USB-RS485 is USB to RS485 converter and can be used with any computer with USB including OLinuXino.

A20-OLinuXino-MICRO, A64-OLinuXino, A13-OLinuXino, A33-OLinuXino, iMX233-OLinuXino have Audio input, for these boards we got very compact and flexible PC-MIC-3.5MM

mic

For these who deal with tiny SMT parts we got stackable X*Y smt SMT-BOX-25x32x22 with spring loaded cap:

smd-smt-box

SLD-SPONGE is soldering tip cleaning sponge:

sponge

SLD-STAND is metal stand for soldering irons with place for soldering sponge:

SLD-STAND

CONNECTOR-GX16-4 is robust connector for panel mounting and can connect up to 220V/20A:

GX16-4

WIRE-CLIP-300F is female connector at one end which easy connects to boards with headers and sprint loaded contact at the other end. If you make signal analyzer with FPGA boards these clip wire connectors are very handy to attach to existing boards:

WIRE-CLIP-300F

ALUMINUM-HEATSINK-TO-220 is low cost heatsink for TO-220 devices like voltage regulators and transistors:

ТО220

 

 

If you need second (or third) Fast Gigabit Ethernet interface on your embedded Linux computer or desktop our Open Source Hardware OSHW USB-Gigabit adapter is what you need!

USB-GIGABITa

Many of our customers ask if we can design board with two or three Gigabit Ethernet interfaces. The Allwinner chips we use for OLinuXino are general purpose not communication chips so they usually have single Ethernet. The Sitara SOC we use AM335X advertise to have more than one Ethernet interface but it’s marketing as these are virtual interface i.e. share transfer speed.

USB-Gigabit allow you to add 10/100/1000Mbit interface to any of your computers which has USB host. It supports USB 1.1, USB 2.0 and USB 3.0 interfaces and speed depend on your USB port speed.

Our tests with A20 OLinuXino boards with USB 2.0 host interface show 319Mbit of Upload and 295Mbit of Download speed i.e. x3 times more than our other USB-Ethernet-AX88772B interface.

USB-ISO USB 2.0 Full Speed insulator passed all EMC tests in certified laboratory and now can bear CE mark!

USB-ISO-01

After our first product which pass CE requirements (ESP32-POE-ISO) now we are happy to announce that we have second product which pass CE standard tests.

USB-ISO have been tested and passed these standards tests in certified laboratory:

  • EN 55032:2015
  • EN 55035: 2017
  • EN 61000-3-2: 2014
  • EN 61000-3-3: 2013

usbisotst

So it can be now CE marked.

 

It’s Friday again and time for our Guess What is this Quiz

Screenshot from 2019-04-19 17-39-37

We just finished the routing of this new board, so the question is Guess what is it?

Screenshot from 2019-04-19 17-39-51.png

It uses Quectel EG21-G module which works anywhere in the world covering all GSM standards and frequencies. It also has GNSS build-in.

Screenshot from 2019-04-19 17-40-08

It also can connect to any network 2G-3G-4G whichever is available (sorry no 5G yet 😉 ).

Once the prototypes are ready and check we are preparing Crowd Supply campaign for it! Hint Fits perfect to LoRa-GATEWAY and allow connection where no wires and optics like mountain hubs, remote areas etc.

You can post here or retweet/share/boost on Twitter/Facebook/Mastodon/Diaspora and in Monday we will let Random.org to decide who will win one of our new eduArdu educational board.

Have a nice weekend!

UODATE 22-04-2019: Random.org selected @netsigi as winner!

 

Ever wondered how much current your USB devices use and how stabile is your USB voltage? Now you can measure!

USB-POWER

Some USB devices like 3G modems, WiFi etc in active mode draw lot of current and cause problems, to monitor the current consumption and how stabile is your USB voltage you can use this USB-POWER-METER.

The consumption is measured and displayed with 10mA accuracy. Voltage with 10mV accuracy.

MOD-RFID1356MIFARE NFC / RFID reader writer for MIFARE 13.56Mhz tags

MOD-RFID1356MIFARE

MOD-RFID1356MIFARE is re-design of our popular RFID card readers. It’s based on NXP PN532 chip and can read and write in ISO/IEC 14443A/MIFARE tags.

Like with MOD-RFID125 and MOD-RFID1356 it’s extremly easy to use. It connects via USB to any computer and creates HID keyboard or CDC serial port. There is no need for any drivers and switching between the modes is very easy with one push button.

WiKi description explains how to use. Read distance is up to 15 cm for ISO cards. We will stock soon 4 different types of tags: ISO card, clamshell, keychain and adhesive sticker.

New product in stock: Micro-USB-OTG-Adapter allow to connect USB devices to your phone and tablet

MICRO-USB-OTG-1MICRO-USB-OTG-2

MICRO-USB-OTG-ADAPTER allow you to connect easily USB Flash drives, Keyboards, Mouse, camera, etc USB devices to your phone and tablet.

Small and compact size it slides inside USB-A connector and make it MICRO-USB:

MICRO-USB-OTG-3 MICRO-USB-OTG-4

then you can easily attach to your phone:

MICRO-USB-OTG-5

and to transfer Music, Movies, Documents etc.

 

New product soon to be in stock: MOD-WIFI-AR9271-ANT WiFi USB dongle with Open Source Firmware and Linux drivers

MOD-WIFI-AR9271-ANT-1

AR9271 chipset is the only one with Open Source Firmware and Linux drivers. It has build in Kernel support since Kernel 2.6.35 so if you want to run GNU/Linux clean of non-free binary blobs with unknown content this is the device for you. It will work with your desktop PC, laptop, or SBC like OLinuXino and Raspberry Pi etc.

MOD-WIFI-AR9271-ANT samples are tested and proven to work with all our OLinuXinos and have excellent WiFi reception due to the huge antenna they came with. We have pending order and they will be in stock very soon.

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