blog: Concept2 PM5 logbook data format

(You should find the most recent version of this on my git server )

I recently bought a Concept2 rower and wanted to read the USB logbook data - unfortunately Concept2 neither provides a description of the format nor any Open Source or Unix software. I tried to figure out the data format on my own, then Ryan Moe’s work filled the gaps:

The data is split across two files, LogDataAccessTbl.bin and LogDataStorage.bin. The former provides information about the location of the actual workout data in LogDataStorage.


Each entry in LogDataAccessTbl is 32 bytes, multibyte entries are Little Endian:

Byte Meaning
0 Magic 0xF0
1 Workout type
2-3 Interval rest time*
4-5 Workout name*
6-7 N/A
8-9 Timestamp*
10-11 N/A
12-13 No. of Splits*
14-15 Duration/Distance*
16-17 Record offset in LogDataStorage.bin
18-23 N/A
24-25 Size of record in bytes
26-27 Index
28-31 N/A

( * unimportant, because either redundant in actual record or unreliable )

Workout Types

Value Type
0x01 Free Row
0x03 Single Distance
0x05 Single Time
0x06 Timed Interval
0x07 Distance Interval
0x08 Variable Interval
0x0A Single Calorie


Each entry in LogDataStorage has a header and a number of splits or intervals. The header size is either 50 bytes (workout types 0x01, 0x03, 0x05, 0x0A) or 52 bytes (others). The size of each split frame is 32 bytes for all workouts except type 0x08, where it is 48 bytes. Multibyte entries are, contrary to LogDataAccessTbl.bin Big Endian(!)

Header (types 0x01 - 0x05, 0x0A)

Byte Meaning
0 Magic 0x95
1 Type of workout
2-3 N/A
4-7 Serial number
8-11 Timestamp
12-13 User ID
14-17 N/A
18 Record ID
19-21 Magic 0x000000
22-23 Total Duration
24-27 Total Distance
28 SPM
29 Split Info
30-31 Split Size
32-49 N/A

Header (Fixed Intervals)

Byte Meaning
0-18 As above
19 Number of splits
20-21 Split size
22-23 Interval rest time
24-27 Total Work Duration
28-29 Total Rest Distance
30-51 N/A

Header (Variable Intervals)

Byte Meaning
0-18 As above
19 Number of splits
20-21 Split size
20-23 Total Work Duration
24-27 Total Work Distance
30-51 N/A

Timestamp format (bytes 8-11)

Bits Meaning
0-6 year after 2000
7-11 day
12-15 month
16-23 hour
24-31 minute

Split Frame (Non-Interval Types)

Byte Meaning
0-1 Split Duration/Distance
2 Heart Rate
4-31 N/A

Interval Frame (Timed Interval, Distance Interval)

Byte Meaning
0-1 Split Duration/Distance
2 Heart Rate
3 Rest Heart Rate
5-31 N/A

Variable Interval Frame

Byte Meaning
0 Split Type
2-5 Work Interval Time
6-9 Work Interval Distance
10 Heart Rate
11 Rest Heart Rate
12-13 Interval Rest Time
14-15 Interval Rest Distance
16-47 N/A
Posted in programming sports rowing concept2
2018-03-04 18:36 UTC