Month: October 2015

Switched to HTTPS

jeremy, Leave a comment

The title says it all. I bought a SSL certificate at Xolphin, installed it and then I had to hunt down all the things that didn’t work anymore. I even managed to render the HTTP version of autostatic.com unreachable for  about a day. But now everything seems to be working so I activated a rewrite rule that redirects all HTTP traffic to HTTPS. There are some bits that might not work as expected (embedded videos not displaying, warnings about unsecure content) but most of my blog should be accessible now in a secure way. If you encounter any issues, please let me know.

autostatic https

The certificate I’m using is a Comodo Positive SSL certificate with Domain Validation. So I’m getting a padlock but not the green address bar, for a green bar you need at least an Extended Validation certificate and that gets a bit expensive. I generated an Apache SSL configuration with the Mozilla SSL Configuration Generator but left out the OCSP stuff. I did add the HSTS header (HTTP Strict Transport Security header) because it really helped with getting that desired A+ rating in the Qualys SSL Labs SSL Server Test.

Switched to HTTPS

The hardest part

jeremy, , , , , , , , , , 3 Comments

At least, for me. Now I have to code something that enables me to select banks and instruments on my synth module. I’ve settled for pyliblo to talk to ZynAddSubFX but I’m just no coder. My elbow now rests on “Learning Python” from O’Reilly, I started reading it like a year ago but never got past chapter 3 or something. Time to persist, I’ve been wanting to be able to code a little bit for years now.

As a note to self, and maybe it’s helpful for others too, what follows are some of the relevant OSC messages to change banks and instruments in ZynAddSubFX.

Changing banks can be done with /loadbank. pyliblo comes with an example script send_osc.py and loading a bank with send_osc.py works as follows:

send_osc.py 7777 /loadbank ,i 3

7777 is the port ZynAddSubFX runs on. The /loadbank message wants an integer (,i) and ,i 3 loads the fourth bank (Choir and Voice) as ZynAddSubFX starts counting from 0. Bear in mind that this will only load the bank, it won’t change the instrument that is loaded. To load an instrument from a loaded bank the following send_osc.py incantation does the trick:

send_osc.py 7777 /setprogram ,c $'\x03'

So /setprogram loads an instrument from an active bank. It takes a character (,c) as an argument because the program numbers are in hex. But hex are multiple characters so you have to add some escape sequences to make it work (and I lost it there so I could be completely wrong). The above command should load the fourth instrument from the Choir and Voice bank (Voice OOH) as that bank should have been loaded by the previous /loadbank message.

It is also possible to load instrument (.xiz) files. This can be done with the /load_xiz message:

send_osc.py 7777 /load_xiz 0 "/usr/share/zynaddsubfx/banks/Bass/0001-Bass 1.xiz"

This will load the Bass 1 instrument fom the Bass bank into part 1 (remember that ZynAddSubFX starts counting from 0). So to load the Bass 2 instrument into part 2 you’d do the following:

send_osc.py 7777 /load_xiz 1 "/usr/share/zynaddsubfx/banks/Bass/0002-Bass 2.xiz"

So now I have to incorporate this stuff into Python code that gets called when I press buttons on my LCD display. These are the mappings I’d like to accomplish:

  • Up: toggle next bank and display first instrument from that bank
  • Down: toggle previous bank and display first instrument from that bank
  • Left: toggle previous instrument and display instrument
  • Right: toggle next instrument and display instrument
  • Select: select displayed instrument

That shouldn’t be too hard right? Well, first hurdle, pyliblo can only send or dump OSC messages, it doesn’t seem to be able to handle return messages from the OSC server (ZynAddSubFX in this case). To be continued…

Edit: of course sending just messages with pyliblo won’t handle any return messages, you will need a receiving part. But maybe I should take a look at using MIDI with mididings for instance. Thanks Georg Mill for the tip!

The hardest part

Two steps further

jeremy, , , , , , , , , , , , , , 2 Comments

For my little synth module project I created the following systemd unit file /etc/systemd/system/zynaddsubfx.service that starts up a ZynAddSubFX proces at boot time:

[Unit]
Description=ZynAddSubFX

[Service]
Type=forking
User=zynaddsubfx
Group=zynaddsubfx
ExecStart=/usr/local/bin/zynaddsubfx-mpk
ExecStop=/usr/bin/killall zynaddsubfx

[Install]
WantedBy=local-fs.target

/usr/local/bin/zynaddsubfx-mpk is a simple script that starts ZynAddSubFX and connects my Akai MPK:

#!/bin/bash

zynaddsubfx -r 48000 -b 64 -I alsa -O alsa -P 7777 -L /usr/share/zynaddsubfx/banks/SynthPiano/0040-BinaryPiano2.xiz &

while ! aconnect 'MPK mini' 'ZynAddSubFX'
do
  sleep 0.1
done

/usr/local/bin/zynpi.py

/usr/local/bin/zynpi.py in its turn is a small Python script that shows a message and a red LED on a 16×2 LCD display so that I know the synth module is ready to use:

#!/usr/bin/python
# Example using a character LCD plate.
import math
import time

import Adafruit_CharLCD as LCD

# Initialize the LCD using the pins
lcd = LCD.Adafruit_CharLCDPlate()

# Show some basic colors.
lcd.set_color(1.0, 0.0, 0.0)
lcd.clear()
lcd.message('Raspberry Pi 2\nZynAddSubFX')

The LCD is not an Adafruit one though but a cheaper version I found on Dealextreme. It works fine though with the Adafruit LCD Python library. Next step is to figure out if I can use the buttons on the LCD board to change banks and presets.

synth_module_lcd_startup
Raspberry Pi synth module with 16×2 LCD display
synth_module_test_setup
The synth module test environment
Two steps further