Monoprice sells this wacky 6 zone amp with a serial interface. This tiny project wraps the serial interface with a JSON API.

A detailed walk-through is available illustrating the process to use this API easily on a Raspberry Pi

    npm install
    cp etc/systemd/system/6zhmaut-api.service /etc/systemd/system/6zhmaut-api.service
    systemctl enable 6zhmaut-api
    systemctl start 6zhmaut-api

DEVICE = <string> - the serial port device name (defaults to /dev/ttyUSB0)

BAUDRATE = <integer> - the baud rate to use to connect to the device (defaults to 9600)

PORT = <integer> - port for API to listen on (defaults to 8181)

AMPCOUNT = <1|2|3> - the number of amps (you can slave up to two additional amps) (defaults to 1)

REQUERY = <true|false> - re-query the keypads before responding to a /zones request (defaults to false)

CORS = <true|false> - respond to a CORS request with an Access-Control-Allow-Origin=* (defaults to false)

PORT=8181 npm start

or using more environment variables:

PORT=8181 AMPCOUNT=2 REQUERY=false BAUDRATE=115200 CORS=false npm start

You can update the baud rate of the controller to one of the following rates: 9600, 19200, 38400, 57600, 115200, 230400

By default, at power loss, the device is set to run at 9600 BAUD. You can adjust it using the updateBaudRate.js via npm run-script (or directly with node).

OLDBAUDRATE=9600 NEWBAUDRATE=115200 npm run-script baudrate

Notes:

• To reset the baud rate remove power from the controller for 30 seconds - it will reset to 9600 BAUD
• Running npm run-script baudrate with the incorrect connection baud rate will not cause it to lock so intialization scripting could be created to reset the baudrate before the API enables.

DEVICE = <string> - the serial port device name (defaults to /dev/ttyUSB0)

OLDBAUDRATE = <integer> - the current baud rate of the controller (the rate used to initially connect to the device)

NEWBAUDRATE = <integer> - the desired baud rate

[
  {
    "zone": "11",
    "pa": "00",
    "pr": "01",
    "mu": "00",
    "dt": "00",
    "vo": "15",
    "tr": "10",
    "bs": "10",
    "bl": "10",
    "ch": "01",
    "ls": "00"
  },
  {
    "zone": "12",
    "pa": "00",
    "pr": "01",
    "mu": "00",
    "dt": "00",
    "vo": "15",
    "tr": "10",
    "bs": "10",
    "bl": "10",
    "ch": "01",
    "ls": "00"
  },
  {
    "zone": "13",
    "pa": "00",
    "pr": "01",
    "mu": "00",
    "dt": "00",
    "vo": "15",
    "tr": "10",
    "bs": "10",
    "bl": "10",
    "ch": "01",
    "ls": "00"
  },
  {
    "zone": "14",
    "pa": "00",
    "pr": "01",
    "mu": "00",
    "dt": "00",
    "vo": "10",
    "tr": "10",
    "bs": "12",
    "bl": "10",
    "ch": "02",
    "ls": "00"
  },
  {
    "zone": "15",
    "pa": "00",
    "pr": "01",
    "mu": "00",
    "dt": "00",
    "vo": "20",
    "tr": "07",
    "bs": "07",
    "bl": "10",
    "ch": "01",
    "ls": "00"
  },
  {
    "zone": "16",
    "pa": "00",
    "pr": "01",
    "mu": "00",
    "dt": "00",
    "vo": "21",
    "tr": "07",
    "bs": "07",
    "bl": "10",
    "ch": "01",
    "ls": "00"
  }
]

Returns the current status of a specific zone.

{
  "zone": "11",
  "pa": "00",
  "pr": "01",
  "mu": "00",
  "dt": "00",
  "vo": "15",
  "tr": "10",
  "bs": "10",
  "bl": "10",
  "ch": "01",
  "ls": "00"
}

Return the value of a specific attribute in a zone as plain text. Valid attributes are:

pa (send zone 1 to all outputs)
power / pr
mute / mu
do not disturb / dt
volume / vo
treble / tr
bass / bs
balance / bl
channel / source / ch
keypad status / ls

$ curl 192.168.1.254:8181/zones/11/bass
10

Update a zone's attribute using the plain-text value of the body.

pa (send zone 1 to all outputs)
power / pr
mute / mu
do not disturb / dt
volume / vo
treble / tr
bass / bs
balance / bl
channel / source / ch

Here's an example where we turn the bass of zone 11 up:

$ curl 192.168.1.254:8181/zones/11
{"zone":"11","pa":"00","pr":"01","mu":"00","dt":"00","vo":"15","tr":"10","bs":"10","bl":"10","ch":"01","ls":"00"}
$ curl -X POST -d '12' 192.168.1.254:8181/zones/11/bass
{"zone":"11","pa":"00","pr":"01","mu":"00","dt":"00","vo":"15","tr":"10","bs":"12","bl":"10","ch":"01","ls":"00"}

The manual for the 6 zone amp is available (via Monoprice)[https://downloads.monoprice.com/files/manuals/10761_Manual_141028.pdf]

• fork
• create a feature branch
• open a Pull Request