Skip to content


Switch branches/tags

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time

vscpl1drv-can4vscp - VSCP Level I CAN4VSCP Serial Driver

vscpl1drv-can4vscp is a VSCP level I driver (CANAL driver) for hardware devices that export there inner functionality with the VSCP standard serial protocol (CAN4VSCP). A typical such device is the Frankfurt RS-232 module from Grodans Paradis AB.

Several drivers can be loaded allowing simultaneous communication with several devices on different busses.

Filters/masks can be set to limit/select sub amount of events.

As the VSCP serial protocol is very generic this free serial protocol may also be the protocol to use for your own hardware which have some sort of serial port available.


  • Linux
  • Windows

Driver for Linux

Driver for Windows


Install location


From version 14.0.0 the driver is installed in /var/lib/vscp/drivers/level1


From version 14.0.0 the driver is installed in /program files/vscpd/drivers/level1

Configuration string - Windows

All level I drivers are configured using a semicolon separated configuration string.



The first parameter is the serial port to use (COM1, COM2 and so on).

This parameter is mandatory.


The second parameter is the serial baudrate and defaults to 5 which is the code for 115200 Baud.

Configuration string - Linux

All level I drivers are configured using a semicolon separated configuration string.



The first parameter is the serial port to use (/dev/ttyS0, /dev/ttyS1, /dev/ttyUSB0, /dev/ttyUSB1 and so on).

This parameter is mandatory.


The second parameter is the serial baud rate and defaults to 5 which is the code for 115200 Baud.

Baudrate Code Error Windows Linux
115200 0 -1.36% yes yes
128000 1 -2.34% yes no
230400 2 -1.36% no yes
256000 3 -2.34% yes no
460800 4 8.51% no no
500000 5 0% yes yes
625000 6 0% bad no
921600 7 -9.58% no bad
1000000 8 16.67% no bad
9600 9 0.16% yes yes
19200 10 0,16% yes yes
38400 11 0,16% yes yes
57600 12 0.94% yes yes

Tests on Windows and Linux has been done on a Windows 10 machine and on a Ubuntu machine with the USB serial adapter that ship with Frankfurt RS-232.

Typical settings for VSCP daemon config for Linux

<!-- The can4vscp driver -->
<driver enable="false"

Typical settings for VSCP daemon config for Windows

<!-- The can4vscp driver -->
<driver enable="false"
        path="/program files/vscpd/drivers/level1/"


Bits Usage
Bit 0,1 Open Mode
0 - normal
1 - Listen mode
2 - Loopback mode
3 - Reserved
Bit 2 If set the driver will not switch to VSCP mode. That is it must be in VSCP mode. Open will be faster.
Bit 3 If set the driver will wait for an ACK from the physical device for every sent frame. This will slow down sending but make transmission it very secure.
Bit 4 Enable timestamp. The timestamp will be written by the hardware instead of the driver.
Bit 5 Enable hardware handshake.
Bit 6 Enable strict mode. Driver will terminate on all errors.
Bit 7-30 Reserved.
Bit 31 Enable debug messages to LOG_DEBUG, syslog (0x80000000).

Status return

The CanalGetStatus call returns the status structure with the channel_status member having the following meaning:

Bit Description
Bit 0-7 TX Error Counter.
Bit 8-15 RX Error Counter.
Bit 16 Overflow. Cleard by status read.
Bit 17 RX Warning.
Bit 18 TX Warning.
Bit 19 TX bus passive.
Bit 20 RX bus passive.
Bit 21 Reserved.
Bit 22 Reserved.
Bit 23 Reserved.
Bit 24 Reserved.
Bit 25 Reserved.
Bit 26 Reserved.
Bit 27 Reserved.
Bit 28 Reserved.
Bit 29 Bus Passive.
Bit 30 Bus Warning status.
Bit 31 Bus off status

Serial Protocol

You can find the description of the VSCP serial protocol in the VSCP specification.

Install the driver on Linux

Install Debian package

> sudo apt install ./vscpl2drv-can4vscp_1.1.0-1_amd64.deb

using the latest version from the repositories release section.


sudo make install

use the switch --enable-debug if you want a debug build.

Privileges on serial port

Depending on which user you run the VSCP daemon as you may have to give the vscp daemon read/write access to the serial port where the CAN4VSCP adapter is connected to (ttyS0, ttyS1, ttyUSB0, ttyUSB1....).

The VSCP daemon is by default running as the user vscp and a serial adapter usually have read/write access to a group called dialout so we need to add the vscp user to this group. This we can do with

sudo usermod -a -G dialout vscp

now restart the VSCP daemon with

sudo systemctl restart vscpd

Another method is to define a rule for USB serial adapters. You do this by adding a rule file to /etc/dev/rules.d

cd /etc/uidev/rules.d
sudo touch  50-myusb.rules
sudo vim 50-myusb.rules 



to the file and reboot the machine. Note that this gives read/write permissions for all serial USB adapters 0-9.

Even another solution is to run the VSCP daemon as root user but this is not recommended for security reasons.

Install the driver on Linux using vscp private repository

Warning !!! Currently this is very much experimental

wget -O - | sudo apt-key add -

then add

deb buster main
deb eoan main

to the file


replace eoan with the os-release you have installed and debian to debian, ubuntu or raspian

Install the driver on Windows

Install using the binary install file in the release section.

How to build the driver on Linux

git clone
cd vscpl1drv-can4vscp
git submodule update --init
make install

Default install folder is /var/lib/vscp/drivers/level1

You need build-essentials and git installed on your system.

sudo apt update && sudo apt -y upgrade
sudo apt install build-essential git

How to build the driver on Windows

The source contains a Visual Studio project. Use this project to build the driver.


Enable debug output

Set bit 32 of flags (0x8000000) to enable debug output to syslog. This will give diagnostic info that will help to solve many problems. Check the log with

cat /var/log/syslog | grep vscpd

Access rights

The VSCP daemon, VSCP Works or other software that use this driver need to have read/write privileges to any serial ports or similar. For a serial port the easiest way is to issue

chmod a+rw /dev/ttyUSB0

replacing the port with the port you want to use. If this solve the problem you know it is an access rights problem and you can configure correct access rights. In most cases it may not be a good choice to give read/write access to everyone as we do here.

The right way to accomplished this is by adding the user to the "dialout" group. Like this

´´´bash sudo adduser vscp dialout ´´´ Even another method is to create udev rule that allow users access to the ports. Create a file /etc/udev/rules.d/50-myusb.rules and add


to it and restart or unplug/replug the device. Beware that right 666 is as devilish as it looks and give all rights to everyone.

Port name/path change after configuration

As with all USB serial ports on Linux there is a chance that they change position in the USB enumeration tree. That is a port you known as /dev/ttyUSB0 becomes /dev/ttyUSB1 or something like that when you do a change in your configuration.

The solution to this problem is to make a udev rule. Check this writeup on how to do this. A typical example is from one of the test machines here with two USB serial ports. One for an electric meter and one for a CAN4VSCP serial device. It is setup like this

ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="7523", KERNELS=="1-1.4", SYMLINK+="electric_meter"
ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="7523", KERNELS=="1-1.5", SYMLINK+="vscp_serial0"

The serial adepter has the same vendor id and the same product id so we use the enumeration tree to distinguish between them.

There are many Level I drivers (CANAL drivers) available in VSCP & Friends framework that can be used with both VSCP Works and the VSCP Daemon (vscpd) and other tools that interface the drivers using the CANAL standard interface. Added to that many Level II and Level III drivers are available that can be used with the VSCP Daemon.

Level I drivers is documented here.

Level II drivers is documented here

The VSCP project homepage is here

The manual for vscpd contains full documentation. Other documentation can be found on the documentaion portal.

The vscpd source code may be downloaded from Source code for other system components of VSCP & Friends are here


Copyright © 2000-2022 Ake Hedman, Grodans Paradis AB - MIT license.