Fluke Biomedical 4000M+ - Manual (Page 35)

Appendix
Model 4000M+ Communication Protocol
B
B-1
Appendix B
Model 4000M+ Communication Protocol
B.1 Data Formats
All instructions to the 4000M+ are single-character ASCII commands. These commands should be
invoked while the 4000M+ is in the READY condition. Note that the keyboard remains active throughout
communication; therefore, pressing keys while the computer is communicating with the 4000M+ may
cause problems.
Data transmissions from the 4000M+ are in the following formats:
1. Integer expressions are defined as any integer value between –32768 and +32767, inclusive.
These will be sent via the RS-232 link as base 10 ASCII strings. No sign is sent for positive values;
a minus sign is sent for negative values. Leading zeroes are suppressed.
2. Real numbers are defined as non-integer quantities and are sent in scientific notation. For
example, the value, 80.34, is sent as an ASCII string as: +8.034E+01.
3. Field delimiters; numeric quantities are delimited by either the space (ASCII 20H) or the carriage
return-line feed sequence (chr$(13);chr$(10)); allowing the numeric fields to be read by most high-
level languages.
B.2 Setting up for Operation
1. If using a PC or PC compatible, connect the 4000M+ to the COM1 port using a straight RS-232
cable.
2. Initialize the port with the following BASIC statement:
10 OPEN “COM1:9600,N,8,1” AS #1
B.3 The Commands
Read Filter (F)
The command to read the setting of the filter wheel is F. When the 4000M+ receives this character, it
responds by sending an integer representing the filter setting (see Table B-1).
The integer sent will be delimited by a Carriage Return, Line feed (hereafter, represented as <CR><LF>).
The following is a sample program to read the filter wheel setting:
5 REM THESE INSTRUCTIONS READ FILTER SETTING.
10 0 INPUT #1, FILTER