JUMO IMAGO 500 User manual

JIMAGO 500
Multi-channel process and
program controller
B 70.3590.2
Interface Description
05.02/00403594

Contents
1 Introduction 5
1.1 Preface .......................................................................................................... 5
1.2 Typographical conventions ......................................................................... 6
1.2.1 Warning signs ................................................................................................. 6
1.2.2 Note signs ...................................................................................................... 6
1.2.3 Representation ............................................................................................... 6
2 Protocol description 7
2.1 Master-slave principle ................................................................................. 7
2.2 Transmission mode (RTU) ........................................................................... 7
2.3 Device address ............................................................................................. 8
2.4 Timing of the communication ..................................................................... 8
2.4.1 Timing of a data request .............................................................................. 10
2.4.2 Communication during the internal processing time of the slave ................ 11
2.4.3 Communication during the response time of the slave ............................... 11
2.5 Structure of the data blocks ...................................................................... 11
2.6 Error handling ............................................................................................. 11
2.7 Checksum (CRC16) .................................................................................... 13
2.8 Interface ...................................................................................................... 14
3 Functions 15
3.1 Read n words .............................................................................................. 15
3.2 Write one word ........................................................................................... 16
3.3 Write n words .............................................................................................. 17

Contents
4 Data flow 19
5 Address tables 21
5.1 Process data ............................................................................................... 21
5.2 Setpoints ..................................................................................................... 25
5.3 Manual output ............................................................................................. 25
5.4 Controller parameter ................................................................................. 26
5.5 Program start with start data .................................................................... 29
5.6 Manual operating mode with manual data .............................................. 30
5.7 Program transmission ............................................................................... 30
5.8 Commands .................................................................................................. 31
5.9 Frequent setpoint programming ............................................................... 33
5.10 Process value via interface ....................................................................... 34
5.11 Device identification .................................................................................. 34
5.12 Setting the clock ........................................................................................ 35
6 Program example 37

5
1 Introduction
1.1 Preface
Please read these Operating Instructions before commissioning the interface.
Keep the manual in a place that is accessible to all users at all times.
Please assist us to improve these operating instructions, where necessary.
Your suggestions will be appreciated.
Phone [phone]
Fax [phone]
HAll the necessary information for operating the interface is
contained in these operating instructions. However, if any
difficulties should still arise during start-up, please do not carry out
any unauthorized manipulations. You could endanger your rights
under the instrument warranty!
Please contact the nearest subsidiary or the main factory in such a
case.
EWhen returning modules, assemblies or components, the
regulations of EN 100 015 “Protection of electrostatically sensitive
components” must be observed. Use only the appropriate ESD
packaging for transport.
Please note that we cannot accept any liability for damage caused
by ESD (electrostatic discharge).

1 Introduction
6
1.2 Typographical conventions
1.2.1 Warning signs
The symbols for Danger and Caution are used in these operating instructions
under the following conditions:
1.2.2 Note signs
1.2.3 Representation
VDanger This symbol is used when there may be danger to personnel
if the instructions are ignored or not followed correctly!
!Caution This symbol is used when there may be damage to
equipment or data if the instructions are ignored or not
followed correctly!
ECaution This symbol is used where special care is required when
handling components liable to damage through electrostatic
discharge.
"Info This symbol is used when your special attention is drawn to a
remark.
#Reference This symbol refers to further information in other manuals,
chapters or sections.
abc1Footnote Footnotes are remarks that refer to specific points in the text.
Footnotes consist of two parts:
A marker in the text, and the footnote text.
The markers in the text are arranged as continuous superscript
numbers.
The footnote text (in smaller typeface) is placed at the bottom
of the page and starts with a number and a full stop.
0x0010 Hexadecimal
number
A hexadecimal number is identified by being preceded by an
“0x” (here: 16 decimal).

7
2 Protocol description
2.1 Master-slave principle
The communication between a PC (master) and a device (slave) using
MODbus takes place according to the master-slave principle, in the form of a
data request/instruction - response.
The master controls the data exchange, the slaves only have a response
function. They are identified by their device address.
2.2 Transmission mode (RTU)
The transmission mode used is the RTU mode (Remote Terminal Unit). Data
are transmitted in binary format (hexadecimal) with 8 bits. The LSB (least
significant bit) is transmitted first. The ASCII operating mode is not supported.
Data format
The data format describes the structure of a character transmitted. The
following format options are available:
Master
Slave 1 Slave 2 Slave n
Data word Parity bit Stop bit
1/2 bit
Bit number
8 bit — 1 9
8 bit even 1 10
8 bit odd 1 10
8 bit — 2 10

2 Protocol description
8
2.3 Device address
The device address of the slave can be set between 0 and 254. Address 0 is
reserved.
Two forms of data exchange can be distinguished:
Query Data request/instruction by the master to a slave, via the corresponding
device address.
The slave addressed responds.
Broadcast Instruction by the master to all slaves, via the device address 0. The
connected slaves do not respond. A specific setpoint can, for example, be
transmitted to all slaves. In such a case, the correct acceptance of the values
by the slaves should be checked by a subsequent readout of the setpoint.
A data request with device address 0 is not meaningful.
2.4 Timing of the communication
Start and end of a data block are marked by transmission pauses. The
maximum permitted interval between two consecutive characters is three
times the transmission time of a single character.
The character transmission time (the time taken to transmit one character)
depends on the baud rate and the data format that is used (stop bits and
parity bit).
For a data format with 8 data bits, no parity bit and one stop bit, this is:
character transmission time [msec] = 1000 * 9 bits/(baud rate)
For the other data formats it is:
character transmission time [msec]
= 1000 * (8 bits+parity bit+stop bit(s)) bits/(baud rate)
Sequence
HA maximum of 31 slaves can be addressed via the RS422/485
interface.
Data request from master
transmission time = n characters * 1000 * x bits/(baud rate)
Marker for end of data request
3 characters * 1000 * x bits/(baud rate)
Processing of the data request by the slave (max. 250msec)
Response of slave
transmission time = n characters * 1000 * x bits/(baud rate)
Marker for end of response
3 characters * 1000 * x bits/(baud rate)

9
2 Protocol description
Example Marker for end of data request or end of response for 10/9 bit data format
Waiting time = 3 characters * 1000 * 10 bits/(baud rate)
Baud rate [baud] Data format [bit] Waiting time [msec]
(3 characters)
38400 10 0.79
90.71
19200 10 1.57
91.41
9600 10 3.13
92.82

2 Protocol description
10
2.4.1 Timing of a data request
Timing scheme A data request runs according to the following timing scheme:
t0End marker = 3 characters
(the time depends on the baud rate)
t1This time depends on the internal processing.
The maximum processing time is 250 msec.
The minimum response time which can be set is required by the RS485
interface in the master, in order to switch over the interface driver from
transmit to receive. This parameter is not required for the RS422 interface.
t2This time is needed by the controller, to switch over from transmit back to
receive. This is the waiting time which the master has to observe before
presenting a new data request. This time must always be observed, even
when the new data request is directed to a different device.
RS422 interface: t2= 1msec
RS485 interface: t2= 10msec
HA minimum response time can be set in the controller, under the
menu item “Interface”. This preset time is the minimum time which
will be waited before an answer is transmitted (0 — 500 msec). If a
smaller value is set, then the response time may be longer than the
preset value (because the internal processing time is longer), the
controller answers as soon as the internal processing is
completed. A preset time of 0 msec means that the controller
answers with the maximum possible speed.
DatenanfrageMaster
Slave
t
Datenanfrage
Antwort
t2 t0t1t0
Data request Data request
Response