Raspberry Pi S/PDIF DSP box

A playbook to provision a raspberry pi as a DSP box. The original intent is to use it as an effects loop for a MOTU Ultralite. Of course, it can be used with any device capable of S/PDIF connectivity. You could use analog I/O for the PI but I already had a MOTU box and I speculate that it may have higher quality A/D and D/A than a readily availble Ras-Pi converter board would.

Running these instructions should result in a Raspberry pi that will loop the S/PDIF input directly to its output. It will also automatically generate it's own WiFi network for remote control of the DSP.

Requirements

• Raspberry Pi
• S/PDIF Board
• Additional PCB Mount RCA Jacks
• 0.1uF Ceramic Capacitor 0603 Package
• 75 ohm Chip Resistor 0603 Package
• Fresh Raspbian Install
• ansible sudo pip install ansible
• Generate SSH keys if they don't already exist
• USB WiFi transceiver
• Another singleboard CPU. I'm using a nextthingco chip getchip.com

Installation

• You'll need to populate R15 with a 75 Ohm Resistor && C9 with a 0.1uF Capacitor
• You'll need to solder one of the additional RCA Jacks to the S/PDIF Board
• Insert SD Card into reader
• df -h To find the mount path to the SDCARD ie: /dev/sdb
• umount /dev/card1 && umount /dev/card2 etc as many partitions as there are
• unzip /path/to/raspbian-jessie.zip
• sudo dd bs=4M if=/path/to/raspbian-jessie.img of=/dev/card
• Enable SSH access Remount the card && touch /path/to/boot/ssh
• Insert card into PI and power up
• connect pi to network && find ip of the ras pi
• ansible-playbook -i ras.pi.ip.addr, -u pi -k deploy/ansible/user.yml default sudo password is raspberry
• ansible-playbook -i ras.pi.ip.addr, --ask-become-pass deploy/ansible/configure.yml default sudo password is 123456
• I did not see the device appear until I performed a power cycle
• It may be my cheap EDIMAX usb dongle on the pi, but I'm unable to get devices to connect to the AP if security is enabled. So for now, it sets up an open network.
• Connect to the remote SBC, however you need to, and set it to access the PI's wifi network. I was using sudo nmtui it is from the NetworkManager-tui package.
• ssh ras.pi.ip.addr && ansible-playbook provision_remote_machine_blah

holy shit, getting midi data from floorboad is easy http://superuser.com/questions/737531/how-do-i-view-a-midi-device-stream

we haven't parsed it into pure data, yet, but this shouldn't be difficult.