NGALAC/Subsystems
Power
Streaming PC
BIOS setting for Auto-on with power-on (e.g. from switch)
Audio
Gainclones are a DIY version of a $3000 audio system called the GainCard.
NGALAC possesses a LM3886TF based dual supply amp which requires a split rail +28/-28 DC supply
Example DIY circuits which are easy to build with clear instructions
DIY PSU price is very high, will compare to purchase options
Using computer PSU may be possible after boosting +/-12 to +/-28, however, current on -12V line may not be enough to rate maximum wattage
| Qty | Short Name | Price | Part | Link | Part Total |
|---|---|---|---|---|---|
| 1 | Transformer Dual 28V secondaries, 4.6A Max current | $28.00 | VPS56-2300 | Digikey | $28.00 |
| 16 | Diode | $1.00 | MUR860 | Digikey | $16.00 |
| 4 | Linear Voltage Regulator | $2.10 | LM338T | Digikey | $9.00 |
| 8 | Rectifier Diode | $0.20 | LM4002 | Digikey | $1.60 |
| 4 | 1200uF Radial Aluminum Electrolytic Caps | $1.00 - $6.00 (depending on current) | EEU-FS1J102B | Digikey | $24.00 |
| * | Various Caps and Resistors (1W) | $10.00 | * | * | $10.00 |
| Total | $95.00 | ||||
Electrical
- Ground everything and very well, especially anything the human touches.
OBS automation
inputs -> Arduino/RaspberryPi <-> CmdMessenger <-> Serial port <-> USB <-> streaming CPU <-> PyCmdMessenger <-> obs-wc-controller <-> obs
Guardian Process - Windows OBS restart automatically on fail strategy
| OBS Web Socket Plugin | Sets up a websocket API for OBS |
| obs-wc-rc | Python library to interface with OBS websocket API |
| PyCmdMesssenger | Python library for CmdMessenger using serial port |
| CmdMessenger for Arduino | Arduino CmdMessenger library to communicate with PyCmdMessenger on server via serial port |
OBS websocket plugin
obs-wc-rc
Query and send commands to OBS from python (can theoretically control everything)
import asyncio
from obswsrc import OBSWS
from obswsrc.requests import (ResponseStatus,
StartStreamingRequest,
GetStreamingStatusRequest
)
from obswsrc.types import Stream, StreamSettings
async def main():
async with OBSWS('localhost', 4444, 'password') as obsws:
response = await obsws.require(GetStreamingStatusRequest())
print("Streaming: {}".format(response.streaming))
print("Recording: {}".format(response.recording))
loop = asyncio.get_event_loop()
loop.run_until_complete(main())
loop.close()
Output:
Streaming: False Recording: True
Event Listener
import asyncio
import logging
import sys
from obswsrc import OBSWS
from obswsrc.logs import logger
# We will output logging to sys.stdout, as many events might raise errors
# on creation (that's because protocol.json is not perfect) - such errors
# are logged by obs-ws-rc automatically, we just need to see them
logger.setLevel(logging.ERROR)
logger.addHandler(logging.StreamHandler(stream=sys.stdout))
async def main():
async with OBSWS('localhost', 4444, "password") as obsws:
print("Connection established.")
# We will receive events here by awaiting for them (you can await for
# an event of a specific type by providing `type_name` argument to
# the obsws.event() method)
event = await obsws.event()
# Awaited event might be None if connection is closed
while event is not None:
print("Awaited for '{}' event!".format(event.type_name))
event = await obsws.event()
print("Connection terminated.")
loop = asyncio.get_event_loop()
loop.run_until_complete(main())
loop.close()
Output:
Awaited for 'TransitionBegin' event! Awaited for 'SwitchScenes' event! Awaited for 'RecordingStarting' event! Awaited for 'StreamStarting' event!
Arduino
- Debounce buttons
- better debounce - digital filter based
- Pressure switch for "player in front of machine"
- Note: arduino.ArduinoBoard(enable_dtr=False) See: ##Known Issues in PyCmdMessenger
Arduino code using CmdMessenger library for talking through serial port to python orchestrator
#include "CmdMessenger.h"
/* Define available CmdMessenger commands */
enum {
ping,
pong,
player,
lights,
get_state,
ret_state,
error
};
unsigned long debounce[3] = {0, 0, 0};
unsigned long btn_state[3] = {LOW, LOW, LOW};
unsigned long bounce_delay = 75;
int input_pins[3] = {2, 3, 4};
int pressure_btn = 0;
int stream_btn = 1;
int pin = 0;
int output_pins[3] = {5, 6, 7};
int light_state = LOW;
/* Initialize CmdMessenger -- this should match PyCmdMessenger instance */
const int BAUD_RATE = 9600;
CmdMessenger c = CmdMessenger(Serial,',',';','/');
/* Create callback functions to deal with incoming messages */
void do_pong(void){
c.sendCmd(pong, "pong");
}
void is_player(void){
c.sendBinCmd(player, (int)btn_state[pressure_btn]);
}
void blink_lights(void){
light_state = ~light_state;
for(pin=0; pin<3; pin++) {
digitalWrite(output_pins[pin], light_state);
}
}
void send_state(void){
c.sendCmdStart(ret_state);
for(pin=0; pin<3; pin++) {
c.sendCmdBinArg(digitalRead(input_pins[pin]));
}
for(pin=0; pin<3; pin++) {
c.sendCmdBinArg(digitalRead(output_pins[pin]));
}
c.sendCmdEnd();
}
void on_unknown_command(void){
c.sendCmd(error,"Command without callback.");
}
/* Attach callbacks for CmdMessenger commands */
void attach_callbacks(void) {
c.attach(ping, do_pong);
c.attach(player, is_player);
c.attach(lights, blink_lights);
c.attach(get_state, send_state);
c.attach(on_unknown_command);
}
void read_btns(void) {
int reading;
for(pin=0; pin<3; pin++) {
reading = digitalRead(input_pins[pin]);
if (reading != btn_state[pin]) {
debounce[pin] = millis();
}
if ((millis() - debounce[pin]) > bounce_delay) {
if (reading != btn_state[pin]) {
// Do something for that button, need butotn handlers
btn_state[pin] = reading;
}
}
}
}
void setup() {
Serial.begin(BAUD_RATE);
attach_callbacks();
for(pin=0; pin<3; pin++) {
pinMode(input_pins[pin], INPUT);
pinMode(output_pins[pin], OUTPUT);
digitalWrite(output_pins[pin], LOW);
}
}
void loop() {
c.feedinSerialData();
read_btns();
}
Python code to pair with CmdMessenger
import PyCmdMessenger
arduino = PyCmdMessenger.ArduinoBoard("/dev/ttyUSB0", baud_rate=9600)
commands = [['ping', ''],
['pong', 's'],
['player', 'i'],
['lights', ''],
['get_state', ''],
['ret_state', 'i*'],
['error', '']]
c = PyCmdMessenger.CmdMessenger(arduino, commands)
c.send('ping')
msg = c.receive()
print(msg)
c.send('player')
print(c.receive())
# Turn On Lights
c.send('lights')
c.send('get_state')
msg = c.receive()
print(msg)
# Turn off Lights
c.send('lights')
c.send('get_state')
msg = c.receive()
print(msg)
controls = msg[1]
if controls[0] != 0:
print("Start Stream!")
output from running python controller
Connecting to arduino on /dev/ttyUSB0... done.
('pong', ['pong'], 1522043014.6538415)
('player', [0], 1522043014.6666553)
('ret_state', [1, 0, 1, 1, 1, 1], 1522043014.704131)
('ret_state', [1, 0, 1, 0, 0, 0], 1522043014.744068)
Start Stream!
First 3 states are switches set high or low
Last 3 are LED states (or anything else)
Can trigger LED strips or whatever else as we wish, run pre-defined patterns, etc.
Software
Arduino IDE 1.8.1+ * CmdMessenger Python 3.5.4+ * vitualenv, virtualenvwrapper-win, PyCmdMessenger, obs-ws-rc Git
notes:
evtest to check inputs from the IPAC-2 on rpi
add player 2 keys to retropi retroarch config
swap out audio receiver for car amp thing
test autio streaming with mic, cabinet audio, and stream audio
found a woofer to test with (tbd)
usb shit - polling on rpi
keep alives for obs, obs restart on power on, rpi watchdog, faulover OBS instance, switched by obswsrc cannot connect. how will this work with auto start, and how to select which instance is stealing?
impedance matching circuit
static electricity on case
Arduino COM port detection on streaming PC in python