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Makahiya – sound, server and PCB

Hi everybody,

I didn’t do a lot of things on the project since last Wednesday.
Nonetheless, I managed to make the sotware audio codec work!!! Now, I’m able to stream whatever mp3 file on the serial link, decode it on the micro-processor, send it to the codec and hear it in my earphones. I don’t really know what were the errors in my previous code, but now it works and it’s the most important. We have our first completely finished driver, and that’s a good thing as it doesn’t remain a lot of time before the final deadline.

I also had a look to the server. I managed to deploy the database on heroku (a PostgreSQL database was required), but it has a very strange behaviour: if you read it several times, you don’t always have the same result, and the result also depends on the device you use to access the website. So it’ll be necessary to have a look to it. I also read some documentation about Pyramid to really know how it works (I hate doing something without knowing what I do). Finally, I spent some time looking for a way to add security to our server (authentication and authorization). I found one library that allow the users to log in with their Google account, but it doesn’t work with Python 3.x (only Python 2.x). So I’ll continue to look for a better solution.

And our PCB will be sent to the factory tomorrow evening. We must receive them 6 working days later, which is a good news as it will allow us to work on it during the Christmas holidays.

During next week, I will focus my efforts on the server, in order to have it finished when we receive the PCB.

Makahiya – final PCB review, sound and server

Hi everybody,

As said in my last post, I finished the routing of the PCB. Alexis made some reviews, and I did the corresponding corrections. It should be ok now, and the PCB will be sent to the printing factory soon.

I also (it occupied most of my time on Monday and Tuesday in fact) worked on the audio codec (again). You’re possibly fed up with it, and I understand you. I’d never thought it would be so difficult to make it work. But everyday, I go one step further, so I can’t abandon it (and I really want it to work, so I won’t abandon). Now, I’m able to play any music stored in flash when it’s presented as a single block to the software codec. And I can play one music (the one I’ve used for my tests until now) even when it’s read by chunks (and on Tuesday morning, I could send it through the serial link and play it, but on Tuesday afternoon, it didn’t work anymore, don’t know why). But it fails when I try with other musics… I will continue to work on it.

Finally, today, I deployed our (basic) server on Heroku. I spent some times trying to understand how to use git subrepo. And it’s still not completely clear in my minds, even if it seems to work. The database doesn’t work for now on heroku (due to an error caused by waitress), a deeper analysis will be required to fix this problem. And I also wrote a template html file to display the content of the database (the leds values).

During the end of the week, I’ll try to work on the audio codec to solve the last problems. And I will work on the server also (to make pauses between 2 work sessions on the audio). If both work well on Sunday evening, I’ll be very happy.