BOBE EAI488Interface-box activation protocol

BOBE-Industry-Electronic has developed a protocol relevant to interface activation. The protocol allows a range of operating modes for the most diverse fields of application.

BOBE EAI488

Activation of BOBE Interface-boxes

This page describes the command string and the data format of BOBE interface boxes and explains with some examples how the box is to be activated.

A command string is a character sequence which is to be sent to the interface box so that the box carries out actions such as reading in instruments. The command string always consists of seven command parameters with a length of one to three digits. These seven parameters are transfered without separator and make a character sequence of 13 ASCII digits. The sequence is concluded with a carriage return.

CAUTION: The command string must not be concluded with LINE FEED as the BOBE boxes interprete this as cancel sign, interrupt the measurement and display the message E,1110.

Parameters: 1 2 3 4 5 6 7 Termination sign
Designation: Data direction Channel String window End
channel
Foot switch Company number Measurement series
Command string: 1 31 1 01 1 001 001 Carriage return

1. Parameter: Data direction

Length: 1 ASCII-Characters
Options: 0 not used
1 Input with time-out: if the instrument addressed does not respond within a certain time, an error message is displayed and the measurement series is interrupted.
2 Input without time-out: the box waits until the instrument responds or until it receives a termination signal from the host interface.
3 as Option 1, in addition to the measured value string, the channel number of the instrument addressed is transfered. If a measurement series is cancelled, no error message is displayed.
4 as Option 3, without time-out.
5 not used
6 Input of a multi-channel measurement. The multi-channel measurement allows the readout of various measuring channels with the aid of a command string. For this purpose, the measuring channel where the multi-channel measurement starts is entered via parameter 2 and the measuring channel where the measurement ends via Parameter 4. A multi-channel measurement displays the channel number after the measured value string.
Remark: Multi-channel measurements are only possible with instruments which are addressed via an identical company number (see Parameter 6).

2. Parameter: Instrument channel

Length: 2 ASCII-Characters
Options: 00 Identification and software reset. The interface box is reset to its starting condition.
01 Instrument at Channel 1 is read in and processed.
02 Instrument at Channel 2 is read in and processed.
... ...
31 Instrument at Channel 31 is read in and processed.
Remark: For data direction option 6 (1st parameter), the instrument channel indicates the channel where the multi-channel measurement starts. For instrument channel 00, parameters 1, 4, 5 or 6 (except for company number 000, which is superordinated and puts Parameter 2 out of force) and 7 are ignored.

3. Parameter: Beginning of string window

Length: 1 ASCII-Character
Options: 0 is ignored
Remark: This parameter only serves for test purposes.

4. Parameter: End channel

Length: 2 ASCII-Characters
Options: 01 Only instrument at channel 1 is read in.
02 Instruments from the first channel (Parameter 2) to Channel 2 are read in.
... ...
31 All instruments from the first channel (Parameter 2) to Channel 31 are read in.
Remark: This parameter is only evaluated for data direction option 6.

5. Parameter: Foot switch

Length: 1 ASCII-Character
Options: 0 The measured value is transmitted right after sending the command string.
1 The measured value or the series is only processed and transmitted after operating the foot switch.
2 One measured value of a series is processed and transmitted on operating the foot switch.
3 as Option 2, the series (Parameter 7) is set to 000 (corresponds to endless measurement).
4 as Option 0, on operating the foot switch, the following measured value is marked by "T" instead of "M" in the measured value string. The series is continued. Foot switch operations before sending the command string are not deleted.
5 as Option 5, but the series is terminated.
6 as Option 2, foot switch operations before sending the command string are not deleted.
7 as Option 0, the following measured value is marked with "T".
8 as Option 2, the following measured value is marked with "T".
Remark: In case of foot switch operations 1, 2, 3, 6, and 8, the box waits for a foot switch operation. The waiting position can be interrupted by sending one single ASCII character. The box responds by indicating error message E,1101. A new command string can be sent immediately, but it is to be ensured that the time between the first two digits is not greater than 10ms, as otherwise the first digit is interpreted as single termination signal.

6. Parameter: Company number

Length: 3 ASCII-Characters
Options: 000 Identification
001 Measured data of a Mitutoyo Digimatic instrument are expected.
... ...
999 Date of manufacture.
Remark: Parameters 1, 2, 4, 5 and 7 are ignored in case of company number 000.

7. Parameter: Measurement series

Length: 3 ASCII-Characters
Options: 000 Endless measurement.
001 Single measurement.
... ...
999 999 measurements.
Remark: A measurement series can be interrupted by sending a single ASCII character. All ASCII characters except for CARRIAGE RETURN and CONTROL-C are allowed. The termination is confirmed by error message 'E,1110: 'New Input '.

Data format

The Host InterfaceThe BOBE Box can be operated on any computer interface according to RS232C specification. The following interface parameters apply:

Transmission rate: 9600 Baud
Start bits: 1
Data bits: 8
Stop bits: 1
Parity: none

Measured data strings

Measured value identification, measured value, unit and instrument address are separated by commas, respectively!
The measured data string consists of:

Measured value identification Character ‚M' or ‚T''
Number '1'
Measured value, consisting of Plus/minus
8 digits before the comma
Decimal point
6 digits after the comma
Unit  
Instrument address option
Termination sequence Carriage return
Line feed

Example 1: An individual measured value from a Mitutoyo Digimatic instrument on Channel 1 is to be read in without foot switch operation.  

Command string: 1011110001001{CR}
Measured value string: M1,+12345678.123456,mm_{CR}{LF}

Example 2: An individual measured value of a Mitutoyo Digimatic instrument on Channel 2 is to be read in without foot switch operation.

Command string: 3021110001001{CR}
Measured value string: M1,+12345678.123456,in_,_2{CR}{LF}

Identification

Identification with Software Reset. If the channel number 00 is indiacted in the command string, the box responds with its identification string and is reset to the starting condition.

Example:

Command string: 1001110001001{CR}
Measured value string: A,BOBE M-Box16 V8.00{CR}{LF}

Identification with Software Reset. If the channel number 00 is indiacted in the command string, the box responds with its identification string and is reset to the starting condition.

Example:

Command string: 1001110001001{CR}
Measured value string: A,BOBE M-Box16 V8.00{CR}{LF}

Error messages

If errors occur, the box displays an error message. Other than the EAI 488 interface system, no error text is given after the error number. An exact tracking of the error, however, is possible according to the error number.

Example:
E,1101{CR}{LF} - The error number has always 4 digits, leading zeros are not suppressed.

E,0xxx Format error Error numbers under 1000 indicate a format error. The data format of the instrument addressed does not correspond to the specification which is expected under the company number indicated with xxx.
E,1101 Incorrect input The command string entered does not correspond to the definition in length or parameter setting.
E,1103 Not assigned The interface box cannot process instruments with this company number.
E,1104 Instrument missing The instrument called up in the command string is not connected or not on.
E,1110 New input A measurement has been interrupted (this is no error message in the actual sense, but a confirming message).

Further command string examples

Some examples of command strings and their influences on measured value transmission are listed below. All examples can be tested on a PC with the aid of a terminal program (e.g. Windows terminal), only the company number needs to be adjusted to the instrument connected.

1. The Mitutoyo Digimatic instrument (company number 001) on channel # 1 is to be read in without waiting for foot switch operation:

Command string: 1011110001001{CR}
Measured value string: M1,+12345678.123456,mm_{CR}{LF}

2. The Sylvac OptorRS232 instrument (company number 179) on channel # 4 is to be read in 365 times, each individual measured value is to be triggered by foot switch operation. The series can be interrupted by sending a character.

Command string: 1041112179365{CR}
Measured value string: M1,+12345678.123456,mm_{CR}{LF}
  ... 365 times
Termination sign: (e.g.): A
Termination message: E,1110{CR}{LF}

3. The Tesa DigitCal caliper with OptoRS232 interface (company number 109) on channel # 7 is to be read in as endless series, the series is to be triggered by operating the foot switch, the measured value is to be transmitted with instrument channel and on interrupting the series, no termination message is to be displayed.

Command string: 3071111209000{CR}
Measured value string: M1,+12345678.123456,mm_,_1{CR}{LF}
  ... continued until termination
Termination sign: (e.g.): A
Termination message: returns no termination message

4. Instrument # 1 and instrument #2 are to be read in together without waiting for foot switch operation. The channel number of the instrument is to be transmitted.

Command string: 6011020001001{CR}
Measured value string: M1,+12345678.123456,mm_,_1{CR}{LF}
M1,+12345678.123456,mm_,_2{CR}{LF}

5. If an instrument does not respond within the standard reaction time (maximum approx. 2 seconds), the interface generates an error message E,1104. With some instruments (e.g. scales), however, the response time may be much longer. In order to process such instruments, the above error generation can be switched off via the data direction option in the command string in BOBE boxes from Version 3.00 onwards. The Box waits until the instrument responds or until is receives a termination signal via host interface. A Sartorius-MC1 scale on Channel # 6 serves as example: A Sartorius scale (company number 067) on channel # 6 is to be read in without the interface interrupting the read-in process, if the scale does not respond after approx. 2 seconds.

Command string: 2061110067001{CR}
Measured value string: M1,+12345678.123456,kg_{CR}{LF}