Linux Fieldbus Coupler 750-860 - WAGO 750 Series Manual

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Linux Fieldbus Coupler 750-860

Assembly Guidelines/Standards
3 Linux Fieldbus Coupler 750-860
The Linux fieldbus coupler 750-860 is a freely programmable fieldbus coupler
that comprises an ARM microcontroller and a uClinux operating system.
uClinux (microcontroller Linux) is based on kernel version 2.6.
The Linux fieldbus coupler has a 10/100Base Ethernet interface, a serial
interface as well as an internal bus interface for the connection of up to
64 Series 750 and 753 WAGO I/O modules.
The coupler incorporates the 32-bit processor ARM7TDMI without MMU
with a RISC architecture and a frequency of 44 MHz. No MMU means no
memory virtualization. This allows userspace applications to access the entire
memory.
The memory consists of 16 MB RAM, 32 kB NOVRAM and 4 MB Flash.
2.5 MB of the flash memory hold the JFF2 file system. Additionally, the
Linux fieldbus coupler has a real time clock.
The Linux fieldbus coupler is delivered with a base image and the fixed IP
address 192.168.1.3. For many user space applications the base image is the
right platform. It allows fast access via the Linux console, which is provided
by both the Ethernet (telnet) and the serial interface (getty).
The base image is part of the Bord Support Package (BSP) for the Linux
fieldbus coupler. You can download the BSP with the item number 759-914
from the WAGO homepage free of charge. The BSP contains the source code
for the Kernel 2.6 and the boot loader (U-Boot), the ARM elf toolchain for
x86 systems as well as many user space applications. Sample user space
applications are an excellent starting point for the development of your own
applications.
The process data of the I/O modules are provided by the internal bus driver,
which is a dynamic loadable module, in separate process images for inputs and
outputs. To access these process images from user space applications, you can
use an internal bus API which, in the simplest case, only needs the functions
kbusOpen(), kbusUpdate() and kbusClose().
The CGI interface of the Web Server (BOA) is another special feature of the
base image. You can create powerful Web applications provided with total
access to the process data via the Common Gateway Interface (CGI).
Additionally, you have access to an FTP server, a DHCP client, a DNS client,
a SNTP client, and to NFS support.
WAGO-I/O-SYSTEM 750
Linux Fieldbus Coupler