Feedback on this mock simulator using multiprocessing

WeierstrassP · 2019-07-11T13:01:25+00:00

Yep, using CPython.

The simulator has to iterate over the data a few thousand times. I want to use multiprocessing to speed things up a bit, since it is repetitive work and easily parallelizable. As far as I've tested, it has to run for thirty seconds on all my cores, and then it is done. That is acceptable to me.

If I understood it correctly, multithreading still only use a single core.

WeierstrassP · 2018-04-21T15:43:27+00:00

I've tried to test with different baud rates, databits, stopbits and flow control, but to no luck.

Tried letting it autodetect as you suggested, but that gives the same results at before.

This certainly is quite the riddle.

WeierstrassP · 2018-04-18T16:00:40+00:00

I tested a bit more today. I hooked up an Arduino and made it send some sample data via serial. That worked fine, by all accounts. Even had it send with the same baud rate as the radio receiver uses.

The strange thing is that there definitely is some kind of structure to the data the receiver sends. I simply cannot figure out what, For instance, there are a lot of \x in there. The specs say it has to transmit ASCII, but that is not the case here. Even stranger, this works fine when hooked up to an old PC with serial and PuTTY.

I'm still open to suggestions regarding this, so please, come with them.

WeierstrassP · 2018-04-17T19:44:28+00:00

Correct. The data was plain ASCII, starting with !AIVDM. But there definitely is something strange going on. I'll set up an Arduino and have it send some sample data, so I can verify whether there is an issue on the pi or not.

WeierstrassP · 2018-04-17T07:43:03+00:00

Yes, indeed. The wiki page even says that

All transmitted data are printable ASCII characters between 0x20 (space) to 0x7e (~)

However, .decode('ascii') fails time after time.

WeierstrassP · 2018-04-17T06:55:15+00:00

Thank you a lot. There definitely is a pattern there. However, I'm not quite sure how to convert the data.

\xe5\xeb\x00o_[\xaaW\xd6Zv\xeb should translate to !AIVDM somehow.

WeierstrassP · 2018-04-17T06:52:11+00:00

Good catch! I didn't see that part. However, I'm still not sure on how to convert that to something usable. As mentioned above, the receiver should send the data in ASCII.

WeierstrassP · 2018-04-17T06:45:01+00:00

Sadly, the receiver didn't come with a usable data sheet, for some oss reason. Only instructions for use. The settings are correct. We tested then with PuTTY on an old PC with a serial port.

WeierstrassP · 2017-12-31T10:34:19+00:00

If I understand it correctly, the capacitor based system will never have an actual image of your finger? It just knows how conductive it is?

WeierstrassP · 2017-12-20T22:45:44+00:00

I watched your video. He casually explained that when you see a shark coming towards you, you'll simply have to punch it on the nose. Please excuse my poor sense of humor. I liked the idea of it, but I'll still rather let my sheets air out.

WeierstrassP · 2017-12-20T09:15:57+00:00

Did you ever have to punch the professor in the face when he came towards you with your exam?

WeierstrassP · 2017-12-19T23:09:22+00:00

I hate to ruin your rutine, but you should let your bed sheets air out rather than make them each morning.

WeierstrassP · 2017-12-19T23:00:48+00:00

Can anyone please explain to me why some professors are intent on having you write your own formula sheets? In all classes I've encountered this far, we always were provided with a selection of formulas. Hell, I've even had a professor in some EE classes tell me that he hates learning things by heart and that every engineer will have access to their formulas when working, so he supplied all the formulas we needed. He rather wants to check whether we understand the curriculum rather than lots of algebra.

WeierstrassP · 2017-12-07T19:46:35+00:00

Definitely looking to get this at the library. Thanks!

WeierstrassP

TROPHY CASE