Each curve frame contains a header with the following
information.
Position |
Description |
0 |
Flag data (format and measurement info) |
1 |
Flag data (format and measurement info) |
2 |
Time stamp |
3 |
Time stamp |
4 |
Source amplitude in dB * 100 |
5 |
Highest value in dB * 100 (or data length) |
6 |
RMS out in dB * 100 |
7 |
Noise reduction |
8 |
Measured data points |
The two 16-bit flag words contain information about the curve type and measurement conditions. When parsing this information, first determine the Curve Frame Format. This can be done by examining bits 10-12 of flag 0.
Bits 10-12 of flag 0 contain the curve frame format:
Value |
Description |
Data Points |
0 |
Pure-tone response with distortion |
64 plus 16 |
1 |
Standard composite |
80 |
2 |
Audiometric |
16 |
3 |
(reserved) [was Audiometric] |
32 |
4 |
Variable length |
Variable |
The next two 16-bit words contain information on the date and time of the measurement. See the Time/Date format topic for more information on parsing this data.