Rs-232 Output Format - WATSON INDUSTRIES AHRS-S305 Owner's Manual

RS-232 Output Format

The nominal RS-232 output consists of a string of decimal ASCII characters sent asynchronously
at regular intervals at about 11.85 strings per second. The string is sent at 9600 baud with eight
data bits, one stop bit and no parity. The contents of the string are formed as follows:
1. A single letter and a space used to indicate the start of the data string. the letter "I"
indicates the start of an inertial data string. The letter "R" indicates the start of a
reference data string. If the letter is in lower case ("i" or "r"), an error overrange
condition is indicated (see below).
2. A seven character string representing the bank angle starting with a "+" or a "-",
followed by three digits, a decimal point, one digit and a space for up to ±179.9 degrees.
3. A six character string representing the elevation angle starting with a "+" or a "-",
followed by two digits, a decimal point, one digit and a space for up to ±89.9 degrees.
4. A six character string representing the heading angle by three digits, a decimal point, one
digit and a space for zero to 359.9 degrees.
5. A six character string representing the X axis accelerometer starting with a space, then a
"+" or a "-", followed by one digit, a decimal point and two digits for up to ±9.99 g.
6. A six character string representing the Y axis accelerometer starting with a space, then a
"+" or a "-", followed by one digit, a decimal point and two digits for up to ±9.99 g.
7. A six character string representing the Z axis accelerometer starting with a space, then a
"+" or a "-", followed by one digit, a decimal point and two digits for up to ±9.99 g.
8. A six character string representing the X axis angular rate starting with a "+" or a "-",
followed by two digits, a decimal point, one digit and a space for up to ±99.9
degrees/second.
9. A six character string representing the Y axis angular rate starting with a "+" or a "-",
followed by two digits, a decimal point, one digit and a space for up to ±99.9
degrees/second.
10. A six character string representing the Z axis angular rate starting with a "+" or a "-",
followed by two digits, a decimal point, one digit and a space for up to ±99.9
degrees/second.
11. A six character string representing the velocity starting with a "+" or a "-", followed by
three digits, a decimal point and one digit for up to ±799.9 Km/hr.
12. The string is terminated by a carriage return. There will then be a short interval with no
data transmission before the next string begins.
Watson Industries, Inc AHRS-S305 Rev J 03/22/2018
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