Vaisala standard pressure message can be used to receive pressure data. Data fields are separated with whitespace and missing data is identified with a solidi (/) or an asterisk (*) character:
<SOH>PTB<id><STX><err><SP><p><SP><p3h><SP><a3h><SP><p1><SP><p2><SP><p3><ETX>
<chk><CR><LF>| Name | Description |
|---|---|
<SOH> |
ASCII character, Start of header #001 |
PTB |
Fixed characters |
| <id> | Sensor ID: 3 characters, fixed length, leading whitespaces when
needed. Due to leading whitespaces, every whitespace must be replaced with an asterisk
(*) in the display Sensor ID configuration. For
example, for pressure sensor ID 5 must be typed as **5. |
<STX> |
ASCII character, Start of text, #002 |
| <err> | Transducer status code, 1 to 3 characters, for example 000 |
<SP> |
Whitespace |
| <p> | Pressure (average of measurements <p1>, <p2>, and <p3>) |
| <p3h> | 3-hour trend, pressure change during last 3 hours |
| <a3h> | 3-hour tendency according to WMO code table Manual on Codes Vol. 1.1, International Codes, Part A – Alphanumerical Codes, 1995 Edition, WMO – No. C, Code Table 0200:a. |
| <p1> | Pressure from barometer module 1 |
| <p2> | Pressure from barometer module 2 |
| <p3> | Pressure from barometer module 3 |
<ETX> |
ASCII character, End of text, #003 |
<chk> |
Modulus-65536 (CS4) checksum, hexadecimal format |
<CR> |
Carriage return code, ASCII 0Dh |
<LF> |
Line feed code, ASCII 0Ah |
Example of pressure message
<SOH>PTB 5<STX>000 1012.6 -1.4 7 1012.6 1012.7 1012.5<ETX>0B7D<CR><LF>PTB330 command to set Vaisala standard pressure message
FORM #001 “PTB” ADDR #002 ERR “ “ 4.2 P “ “ P3H “ “ A3H “ “ P1 “ “ P2 “ “ P3 #003 CS4 #rn