VOLTCRAFT DO-101 - RS232 Data Interface

11. RS232 port
Themeteristtedwithaserialinterfaceforexchangingdatawithacomputer.Thiscanbefound
on the right hand side under the lid. The interface is in the form of a 3.5mm jack plug socket and
requires a compatible data cable, which is an optional extra.
The data cable has the following components:
Jack plug 3.5 mm mono 9-pole Sub D socket for PC (serial port)
Centrecontact→ Pin 4
Externalcontact→ Pin 2
A 2.2 KOhm is required between pin 2 and pin 5.
The serial data signal is made up of 16 Bits in the following order:
D15 D14 D13 D12 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0
Each data bit has the following function:
D15 Start symbol
D14 4
D13 When the upper display is output = 1
When the lower display is output = 2
D12+D11 Displayed unit of measurement: mg/L = 07 // %O2 = 06 // °C = 01 // °F = 02
D10 Polarity; 0=positive; 1=negative
D9 Decimal point (DP) at the appropriate place (right to left); 0 = no DP; 1 =
1DP; 2 = 2DP; 3 = 3DP
D8 to D1 Measured value (D8 = largest digit (MSD), D1 = lowest digit (LSD)). If the
display shows 1234, the following bit set (D8 – D1) will be used: “00001234”
D0 End symbol
The RS232 data format is: 9600, N, 8, 1
Baud rate: 9600
Parity bit: No parity bit (N)
Data bit number: 8
Stop bit: 1 stop bit
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