I've written a program to record every stroke of a workout then export the data as a .tcx file. It is basically an upgraded version of the example program on the PMI website. Please note that I am NOT a programmer so there are no doubt a number of errors. If you want to fix my code, please feel free.
It will display a (sort of) clone of the PM3/4 and will display the intervals as they occur on the screen (up to 12). The splits may be slightly different from those displayed on the actual PM due to where in the stroke the data is collected. You will probably only notice a difference on shorter intervals.
To start:
Download the unimaginatively named file from here: https://www.dropbox.com/s/zj4kd375wl802 ... .xlsm?dl=0
You will need to download and install the PMI in Microsoft Excel from this link: http://indoorsportservices.co.uk/software/pmi. Follow the enclosed instructions on installing (Windows only). You will then need to enable Active X and macros in Excel using the trust centre settings under Options.
Connect via a USB cable to your PM. Select either "Record a session" or "Maximum power test". Click on the purple square to activate the link between PC and PM. Select 'Manual' on the PM. Setup your workout (or just row) on the PM then click on "Start Output" on the PC. When you are finished, click on "Stop Output". When you close the window, it will ask if you want to save your workout and export as tcx. The workout will be saved as an extra tab in the Excel file.
DO NOT delete the 'Output' tab. The .tcx file will have the same name as the tab and will be placed in the folder you select. You can also create the .tcx at a later date by clicking the button on the relevant tab. You should then be able to import into garmin connect. Note: If you change the workout type in Garmin Connect to 'indoor rowing' instead of 'Biking', you will lose the cadence graph but will still retain the cadence average and maximum figures.
The program will only work in Windows. I have tested using VMware (on a Macbook) with Windows 7 and Excel 2010 on a PM4. I have imported the .tcx files into Garmin Connect but it should work with other software. Please let me know if you have any issues and I will try to resolve them.
I will hopefully add the ability to program the workouts from the PC at a later date.
Cheers,
Scooter