Pc interface, Meter – Xylem 407119A HOT WIRE ANEMOMETERS User Manual
Page 9
Model 407119A Version 4.1 October 2005
9
PC Interface
The 407119A is equipped with a 3.5mm jack (side compartment) for connection to a PC for
data acquisition purposes. The meter’s data output is a 16 bit data stream. To obtain PC
interface cabling and Windows
TM
data acquisition software, contact Extech Instruments.
Instructions for use are provided with the software. The PC interface cable schematic, data
stream protocol, and RS-232 communication settings are provided below.
PC Interface Cable schematic
Protocol for 16-bit data stream
D0
End Word = ‘0D’
D1 & D8
Displayed reading; D1 = LSD; D8 = MSD. For example,
For a displayed reading of 1234, D8 through D1 is 00001234
D9
Decimal point (right to left):
0 = no decimal; 1 = 1 place; 2 = 2 places; 3 = 3 places
D10
Polarity: 0 = positive; 1 = negative
D11 & D12
Displayed unit of measure: 01 =
o
C; 02 =
o
F; 08 = m/s; 09 = knots;
10 = km/hr; 11 = ft/min; 12 = MPH; 84 = CMM; 85 = CFM;
0A = Square meter (area); 0B = Square feet (area)
D13
1 = Upper LCD display digits; 2 = Lower LCD display digits
D14
Always ‘4’
D15
Start word ‘02’
RS-232 Settings
Baud rate: 9600
Parity: No parity
Data bits: 8
Stop bits: 1
Meter
3.5mm jack
Center pin.............................Pin 4
Ground / Shield.....................Pin 2
PC
DB-9 pin
Pin 5
2.2K
Resistor
W