Arc requests

arc_calibrate

Perform internal calibration of an Arc device.

Request

Key	Value
cmd	“arc_calibrate”
data	arc_calibrate data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	arc_calibrate

arc_enable_5v

Enable 5V in expansion port.

Request

Key	Value
cmd	“arc_enable_5v”
data	arc_enable_5v data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.
enable	Boolean	Yes	True enables 5V output, false disables it.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "enable": true
}

Response

Key	Value
cmd	arc_enable_5v

arc_enable_channel

Enable or disable measurement channel.

Available channels

Channel	Description	Unit
mc	Main Current	A
mv	Main Voltage	V
ac	ADC Current	A
av	ADC Voltage	V
sp	Sense+ Voltage	V
sn	Sense- Voltage	V
vb	VBUS	V
vj	DC Jack	V
tp	Temperature	°C
rx	UART logs	text
i1	GPI1	Digital
i2	GPI2	Digital

For Otii 2.x only: In addition to above channels, two more channels are enabled automatically when their respective current channel is enabled:

Channel	Description	Unit
me	Main Energy	J
ae	ADC Energy	J

In Otii 3.0 you must use recording_get_channel_statistics to get the energy for the mc and ac channels.

Request

Key	Value
cmd	“arc_enable_channel”
data	arc_enable_channel data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.
channel	String	Yes	Channel.
enable	Boolean	Yes	True to enable and false to disable channel.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "channel": "mc",
    "enable": true
}

Response

Key	Value
cmd	“arc_enable_channel”

arc_enable_exp_port

Enables the expansion port.

Required to be enabled to use digital pins (GPO, GPI, RX and TX).

Request

Key	Value
cmd	“arc_enable_exp_port”
data	arc_enable_exp_port data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.
enable	Boolean	Yes	True to enable and false to disable exp port.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "enable": true
}

Response

Key	Value
cmd	“arc_enable_exp_port”

arc_enable_uart

Enables RX and TX pins to be a UART.

Required to be disabled to use RX and TX pins as GPI/GPO.

Request

Key	Value
cmd	“arc_enable_uart”
data	arc_enable_uart data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.
enable	Boolean	Yes	True to enable and false to disable UART.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "enable": true
}

Response

Key	Value
cmd	“arc_enable_uart”

arc_get_adc_resistor

Get adc resistor value.

Request

Key	Value
cmd	“arc_get_adc_resistor”
data	arc_get_adc_resistor data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_adc_resistor”
data	arc_get_adc_resistor data

Data

Key	Type	Required	Description
value	Number	Yes	Resistance in Ω.

{
    "value": 4.7
}

arc_get_4wire

Get the 4-wire measurement state. (available from otii version 2.7.1)

Request

Key	Value
cmd	“arc_get_4wire”
data	arc_get_4wire data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_4wire”
data	arc_get_4wire data

Data

Key	Type	Required	Description
value	String	Yes	The current state, “cal_invalid”, “disabled”, “inactive” or “active”.

{
    "value": true
}

@see arc_set_4wire *

arc_get_exp_voltage

Get the voltage of the expansion port.

Request

Key	Value
cmd	“arc_get_exp_voltage”
data	arc_get_exp_voltage data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_exp_voltage”
data	arc_get_exp_voltage data

Data

Key	Type	Required	Description
value	Number	Yes	Expansion port voltage in V.

{
    "value": 3.4
}

arc_get_gpi

Get the state of a GPI pin.

Requires expansion port to be enabled.

Request

Key	Value
cmd	“arc_get_gpi”
data	arc_get_gpi data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.
pin	Number	Yes	Id of the GPI pin, 1 or 2.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "pin": 1
}

Response

Key	Value
cmd	“arc_get_gpi”
data	arc_get_gpi data

Data

Key	Type	Required	Description
value	Boolean	Yes	The state of the GPI pin.

{
    "value": true
}

arc_get_main

Get main power status.

Request

Key	Value
cmd	“arc_get_main”
data	arc_get_main data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_main”
data	arc_get_main data

Data

Key	Type	Required	Description
value	Bool	Yes	True if power is on, otherwise False

{
    "value": true
}

arc_get_main_voltage

Get main voltage value.

Request

Key	Value
cmd	“arc_get_main_voltage”
data	arc_get_main_voltage data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_main_voltage”
data	arc_get_main_voltage data

Data

Key	Type	Required	Description
value	Number	Yes	Voltage in V.

{
    "value": 3.4
}

arc_get_max_current

Get the max allowed current.

Request

Key	Value
cmd	“arc_get_max_current”
data	arc_get_max_current data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_max_current”
data	arc_get_max_current data

Data

Key	Type	Required	Description
value	Number	Yes	The max current in A.

{
    "value": 0.564
}

arc_get_range

Get the current measurement range on the main output.

Request

Key	Value
cmd	“arc_get_range”
data	arc_get_range data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_range”
data	arc_get_range data

Data

Key	Type	Required	Description
range	String	Yes	The current range, “low” or “high”

{
    "range": "high"
}

arc_get_rx

The RX pin can be used as a GPI when the UART is disabled.

Requires expansion port to be enabled.

Request

Key	Value
cmd	“arc_get_rx”
data	arc_get_rx data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_rx”
data	arc_get_rx data

Data

Key	Type	Required	Description
value	Bool	Yes	The state of the RX pin.

{
    "value": true
}

@see arc_enable_exp_port arc_enable_uart

arc_get_src_cur_limit_enabled

Get current state of voltage source current limiting. (available from otii version 2.7.1)

Request

Key	Value
cmd	“arc_get_src_cur_limit_enabled”
data	arc_get_src_cur_limit_enabled data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_src_cur_limit_enabled”
data	arc_get_src_cur_limit_enabled data

Data

Key	Type	Required	Description
enabled	Boolean	Yes	True if set to constant current, false if set to cut-off.

{
    "enabled": true
}

@see arc_set_src_cur_limit_enabled

arc_get_uart_baudrate

Get the UART baud rate.

Request

Key	Value
cmd	“arc_get_uart_baudrate”
data	arc_get_uart_baudrate data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_uart_baudrate”
data	arc_get_uart_baudrate data

Data

Key	Type	Required	Description
value	Number	Yes	The requested baud rate.

{
    "value": 115200
}

arc_get_value

Get value from specified channel.

Command not available for the rx channel.

Request

Key	Value
cmd	“arc_get_value”
data	arc_get_value data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.
channel	String	Yes	The channel name.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "channel": "mc"
}

Response

Key	Value
cmd	“arc_get_value”
data	arc_get_value data

Data

Key	Type	Required	Description
value	Number	Yes	The value in A, V, °C and Digital.

{
    "value": 0.0375
}

@see arc_enable_channel

arc_get_version

Get hardware and firmware versions of device.

Request

Key	Value
cmd	“arc_get_version”
data	arc_get_version data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_version”
data	arc_get_version data

Data

Key	Type	Required	Description
hw_version	String	Yes	The hardware version.
fw_version	String	Yes	The firmware version.

{
    "hw_version": "1.2",
    "fw_version": "1.0.8"
}

arc_is_connected

Check if a device is connected

Request

Key	Value
cmd	“arc_is_connected”
data	arc_is_connected data

Data

Key	Type	Required	Valid values
device_id	String	Device id

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_is_connected”
data	arc_is_connected data

Data

Key	Type	Required	Description
connected	Boolean	Yes	True if device is connected

{
    "connected": true
}

arc_get_4wire

Get the 4-wire measurement state. (available from otii version 2.7.1)

Request

Key	Value
cmd	“arc_get_4wire”
data	arc_get_4wire data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected Arc device.

{
    "device_id": "Arc512031204843494E3130393033313036"
}

Response

Key	Value
cmd	“arc_get_4wire”
data	arc_get_4wire data

Data

Key	Type	Required	Description
value	String	Yes	The current state, “cal_invalid”, “disabled”, “inactive” or “active”.

{
    "value": true
}

@see arc_set_4wire

arc_set_adc_resistor

Set the value of the shunt resistor for the ADC.

Request

Key	Value
cmd	“arc_set_adc_resistor”
data	arc_set_adc_resistor data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
value	Number	Yes	The ADC resistor in Ω (0.001 to 22Ω).

{
    "device_id": "Arc512031204843494E3130393033313036",
    "value": 4.7
}

Response

Parameter	Value
cmd	“arc_set_adc_resistor”

arc_set_exp_voltage

Set the voltage of the expansion port.

Request

Key	Value
cmd	“arc_set_exp_voltage”
data	arc_set_exp_voltage data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
value	Number	Yes	Voltage in V (1.2 - 5V).

{
    "device_id": "Arc512031204843494E3130393033313036",
    "value": 2.7
}

Response

Parameter	Value
cmd	“arc_set_exp_voltage”

arc_set_gpo

Set the state of a GPO.

Requires expansion port to be enabled.

Request

Key	Value
cmd	“arc_set_gpo”
data	arc_set_gpo data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
pin	Number	Yes	Id of the GPI pin, 1 or 2.
value	Boolean	Yes	State of pin

{
    "device_id": "Arc512031204843494E3130393033313036",
    "pin": 1,
    "value": true
}

Response

Parameter	Value
cmd	“arc_set_gpo”

@see arc_enable_exp_port

arc_set_main

Turn on or off main power on a device.

Request

Key	Value
cmd	“arc_set_main”
data	arc_set_main data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected device.
enable	Boolean	Yes	True turns on power, false turns off power.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "enable": true
}

Response

Key	Value
cmd	“arc_set_main”

arc_set_main_current

Set the main current on Arc.

Used when the Otii device is set in constant current mode.

Request

Key	Value
cmd	“arc_set_main_current”
data	arc_set_main_current data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
value	Number	Yes	Current to set in A.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "value": 0.005
}

Response

Parameter	Value
cmd	“arc_set_main_current”

arc_set_main_voltage

Set the main voltage on Arc.

Used when the Otii device is set in constant voltage mode.

Request

Key	Value
cmd	“arc_set_main_voltage”
data	arc_set_main_voltage data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
value	Number	Yes	Voltage to set in V.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "value": 2.3
}

Response

Parameter	Value
cmd	“arc_set_main_voltage”

arc_set_max_current

When the current exceeds this value, the main power will cut off.

Request

Key	Value
cmd	“arc_set_max_current”
data	arc_set_max_current data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
value	Number	Yes	Max current in A.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "value": 0.6
}

Response

Parameter	Value
cmd	“arc_set_max_current”

arc_set_power_regulation

Set power regulation mode.

Request

Key	Value
cmd	“arc_set_power_regulation”
data	arc_set_power_regulation data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
mode	String	Yes	One of the following: “voltage”, “current”, “inline”, “off”.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "mode": "current"
}

Response

Parameter	Value
cmd	“arc_set_power_regulation”

arc_set_range

Set the main outputs measurement range.

Request

Key	Value
cmd	“arc_set_range”
data	arc_set_range data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
range	String	Yes	“low” or “high”. “low” will enable auto-range, “high” will force the use of high-range.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "range": "low"
}

Response

Parameter	Value
cmd	“arc_set_range”

arc_set_src_cur_limit_enabled

Enable voltage source current limit (CC) operation. (available from otii version 2.7.1)

Request

Key	Value
cmd	“arc_set_src_cur_limit_enabled”
data	arc_set_src_cur_limit_enabled data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
enable	Boolean	Yes	True means enable constant current, false means cut-off.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "enable": true
}

Response

Parameter	Value
cmd	“arc_set_src_cur_limit_enabled”

arc_set_tx

The TX pin can be used as a GPO when the UART is disabled.

Requires expansion port to be enabled.

Request

Key	Value
cmd	“arc_set_tx”
data	arc_set_tx data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
value	Boolean	Yes	State of tx pin

{
    "device_id": "Arc512031204843494E3130393033313036",
    "value": true
}

Response

Parameter	Value
cmd	“arc_set_tx”

@see arc_enable_exp_port arc_enable_uart

arc_set_uart_baudrate

Set UART baud rate.

Request

Key	Value
cmd	“arc_set_uart_baudrate”
data	arc_set_uart_baudrate data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
value	Number	Yes	Baud rate to set.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "value": 115200
}

Response

Parameter	Value
cmd	“arc_set_uart_baudrate”

arc_write_tx

Write data to TX.

Requires expansion port and UART to be enabled.

Request

Key	Value
cmd	“arc_write_tx”
data	arc_write_tx data

Data

Key	Type	Required	Valid values
device_id	String	Yes	Device id for a connected arc.
value	String	Yes	Data to write.

{
    "device_id": "Arc512031204843494E3130393033313036",
    "value": "Start"
}

Response

Parameter	Value
cmd	“arc_write_tx”

@see arc_enable_exp_port arc_enable_uart