Aladin Transfer Protocol
I will not reprint the whole protocol here but you can download it in the appropriate section. If you know the meaning of currently-unknown bits, please send me an email.
Basicaly, the Aladin first sends global information (such as the number of dives, the time tag,...) then the dive profiles. Dives provile are limited to a combined length of 200 minutes. Since the sampling rate of the depth is .05Hz (or 1 sample every 20 seconds), this means a maximum of 600 samples. The profile also contains alarm data at each sample time. After sending the profiles, some more global info is sent (like the model of the computer).
A dive profile is 2050 bytes long and sent with the following RS232 parameters:
- 19200 bauds
- 1 stop bit
- no parity
It thus takes more or less 2050/19200*8=0.8 second to transfer the dive profile, hence the little time lag when entering the logbook mode.
The PC 'sees' the Aladin when it is connected because the 100Hz idle waveform (which is sent all te time) creates errors on its port. When good bytes arrive, the PC uses them; it ends the transfer when garbage date is detected. Errors are thus used and perfectly normal (just in case you would like to make your own transfer software...)
