The ip-link control block (cb ip-link) – BECKHOFF CX1100-000x User Manual

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Product overview

36

Embedded PC

The IP-Link Control Block (CB IP-Link)

This section describes the layout of the control block for the IP-Link bus of CX1100-0003. This control block is
located in the memory just below the I/O region of the K-bus interface.

CB IP-Link

Offset

Default

0xFB0[2]

IPL 2 byte plc interface to CX1100-0002/3

0xFB2[2]

IPL 2 byte plc interface from CX1100-0002/3

0xFB4[2]

IPL diagnosis to CX1100-0002/3

0xFB6[2]

IPL diagnosis from CX1100-0002/3

0xFB8

IPL service request bitfield

0xFB9

IPL service response bitfield

0xFBA

IPL error code

0xFBB

IPL error argument

0xFBC[2]

IPL base ptr Inputs

0x400

0xFBE[2]

IPL base ptr Outputs

0x700

0xFC0-0xFC1

IPL cycle count

0xFC2-0xFC3

IPL cycle time [µs]

0xFC4

IPL bus status

0xFC5-0xFCE

Reserved

0xFCF

Retry counter

IP-Link 2 byte plc interface to CX1100-0003 / IP-Link 2 byte plc interface from

CX1100-0003

These two bytes for each direction - from the main CPU to CX1100 and back - special communication with the
register model of the I/O microcontroller. Through this interface, a communication to K-Bus terminals can take place.
The so called register model description can be found in the hardware description manuals of the terminals and bus
couplers. This communication is typically used for extended diagnosis or configuration of terminals if they need to
deviate from the delivery standard, e.g. changing the baud rate for RS232-terminals or gain/offset values with analog
terminals.

IP-Link diagnosis to CX1100-0003 / IP-Link diagnosis from CX1100-0003

With these two bytes in each direction it is possible to retrieve diagnostic information from the attached terminals.
Since the same diagnostic information is reflected in the process image input area per each terminals, there is in
general no need to use this interface.

IP-Link service request bitfield / IP-Link service response bitfield

IThese two bytes contain a sequence of bits, by which certain service functions may be executed. The service
function is invoked by setting the appropriate request bit, the controller executes and sets the response bit. Before
the same function can be invoked again, the request bit must be set to zero and wait until the response bit is also set
to zero. An execution error is signaled by raising response bit 7.

Bitfeld

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Request

-

-

-

-

-

-

Free Run

Reset Bus

Response

Error

-

-

-

-

-

Free Run Active

Reset Done

Reset Bus:
with this bit, a reset of the K-Bus may be performed. This is necessary after the occurrence of an error (detected by
examination of the "Processdata error"-byte in the GCB) e.g. after a terminal has been pulled out. After performing

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