We offer free software for your espresso machine. It turns ordinary portafilter machines into sophisticated shot brewers with precise control over temperature, pressure and dispensed weight.

caffè! leva! ristretto!

Compatible hardware

arturo, faustino (specs below for arturo) ito Pollin's avr-net-io and easy-kit 2 (specs below for easy kit 2)
Control  functions PID, pump, valves PID, pump, valve PID
Dimensions 90x90mm 65x56mm 90x90mm
Typical installation type Internal  Internal Internal
Microcontroller(s) ATMega1284 ATMega1284 +
Xtensa LX106
ATMega1284
Display Optional
(OLED graphics display or 3x16 LCD)
Optional
(OLED graphics display)
Optional
(OLED graphics display or 3x16 LCD)
On-board power supply No Optional
(100-240VAC/50-60hz)
No
Solid state relays (max) Up to 8 for:
Pump
Valve
PID 1
PID 2
Refill pump/valve
Valve wand 1
Valve wand 2
Grinder
Up to 4 for:
Pump
Valve
PID 1
PID 2
Up to 3 for:
PID 1
PID 2
Grinder
On-board solid state relays - 2 (pump, valve),
max. 240V/1A
-
Real time clock with battery Yes - Yes
Flow meter input4 1 1 1
Pressure sensor input5 1 1 1
Water tank sensor Switch or capacitive SAECO sensor (P14701A1Z) Switch or capacitive SAECO sensor (P14701A1Z) Switch or capacitive SAECO sensor (P14701A1Z)
Max. ambient temperature 70ºC
70ºC display
60ºC ito
70ºC
Input elements Six buttons on display module and/or temperature selector toggle switch Rotary encoder with push-button OR two buttons on display module Six buttons on display module and/or temperature selector toggle switch
Signaling White LED for original boiler lamp
(dimmable)
White LED for original boiler lamp
(dimmable)
White LED for original boiler lamp
(dimmable)
LED outputs 10 LED, dimmable 2 LED, dimmable +
 2 on-board LED (power and Wifi state)
5 LED, dimmable
LED function Configurable Configurable Configurable
Logic-level contact inputs for user-assigned functions 14  0 - 41 8
Mains voltage sense inputs
(zero cross detecion)
- 1
(opto-isolated)
-
Temperature sensor inputs 8
(Simultaneous use: 5)
2
(Simultaneous use: 2)
6
(Simultaneous use: 5)
Digital temperature sensor inputs
(TSic 306 TO92)
5 2 5
Analog inputs 4 x 24bit + 3 x 10bit 2 x 10bit 3 x 10bit
Supported analog sensors Pressure sensor,
Paddle6,
2 x Pt100 or Pt1000,
4 x Thermocouple "Type K",
KTY (temperature sensor)
Pressure sensor,
Paddle6
Pressure sensor,
KTY (temperature sensor)
Measurement resolution 0.0625ºC (Pt1000) or
0.1ºC (TSic)
0.1ºC (TSic) 0.1ºC (TSic)
Measurement range (max) 150ºC 150ºC 150ºC
Calibrated sensor | Measurement error (max) Yes | max. 0.3ºC at 90ºC (TSIC) Yes | max. 0.3ºC at 90ºC (TSIC) Yes | max. 0.3ºC at 90ºC (TSIC)
Buzzer Yes Yes Yes
Safe USB (galvanic isolation) Yes No USB port Yes
Vibration-resistant connectors Yes Yes Yes
PID temperature control
Cycle time 1s 1s 1s
Internal resolution 0.0625ºC 0.0625ºC 0.0625ºC
Number of PID controllers 2 Channels 2 Channels 2 Channels
Steam control Thermostat or PID
(setpoint controlled by logic-level steam switch; does not require extra relay)
Thermostat or PID
(requires extra relay for second PID channel)
Thermostat or PID
(requires extra relay for second PID channel)
Context-specific PID configuration for warm-up, idle phase, shots Yes Yes Yes
Anti-Windup overshoot reduction Yes Yes Yes
Output limiting Yes Yes Yes
Integral freeze Yes Yes Yes
Feed-Foward control Yes (via flow meter) Yes (via flow meter) Yes (via flow meter)
Ramp & Soak (programmable
output | setpoint curves)
Yes | Yes Yes | Yes Yes | Yes
Combine physical sensors into virtual sensor Yes Yes Yes
Autotuning Yes
(configurable)
Yes
(configurable)
Yes
(configurable)
ECO mode | Standby Yes | Yes
(configurable)
Yes | Yes
(configurable)
Yes | Yes
(configurable)
Sensor calibration via
offset correction | gain correction
Yes | Yes Yes | Yes Yes | Yes
Grouphead offset correction Yes Yes Yes
Digital filters 3
(Sensor, D component of PID and PID output)
3
(Sensor, D component of PID and PID output)
3
(Sensor, D component of PID and PID output)
Pump and valve control
Firmware-controlled valves 4 1 -
Pump power control Nearly stepless3
(Phase angle control)
Nearly stepless3
(Phase angle control)
-
Pressure control loop with feedback from sensor Yes Yes -
Pressure profiling (programmed pressure curves) Yes Yes -
Power profiling (programmed pump power curves) Yes Yes  -
Absolute paddle (analog)6 Yes Yes -
Incremental paddle (digital) - Yes
(Rotary encoder)
-
Preinfusion (firmware-controlled PI pressure) Yes Yes -
On-off pseudo preinfusion Yes Yes -
Flow rate limiting Yes Yes -
Dosing by volume with flow meter Yes Yes -
Dosing by time Yes Yes -
Dosing by weight with Bluetooth scale (gravimetric dosing) - Yes
(with Skale 2, Felicita Arc, Eureka Precisa)
-
Warm-up program Yes Yes -
Grouphead flush program Yes Yes -
Backflush program Yes Yes -
Descale program Yes Yes -
Special functions
Shot timer (visual | acoustic) Yes | Yes Yes | Yes Yes | Yes
Grinder control (grind timer) Yes - Yes
Limescale monitoring Yes Yes Yes
Backflush reminder Yes Yes Yes
Water filter monitor Yes Yes Yes
Empty tank alarm Yes Yes Yes
Timer function with weekday timer Yes Maybe later2 Yes
Energy saving with configurable ECO mode Yes Yes Yes
Shot logger (recording in non-volatile memory) Yes
(in on-board EEPROM)
Maybe later
(in EPS8266 flash memory)
-
Automatic, dimmable grouphead illumination Yes Yes Yes
Protective functions (limiting of pump run time, limiting of heat-on time etc.) Yes Yes Some
Interfaces USB, Bluetooth 2.0 Wifi, Bluetooth LE, Serial7 USB
Virtual LCD software Windows
Linux
(Mac OS X experimental)
Windows
Linux
Mac OS X
Android
Windows
Linux
(Mac OS X experimental)
Status monitor software to view view plots, data, gauges Windows
Linux
(Mac OS X experimental)
Windows
Linux
Mac OS X
Android
Windows
Linux
(Mac OS X experimental)
Documentation
Installation guide and firmware manual ca. 236 pages ca. 270 pages ca. 143 pages
 
1: Up to 4 pins at the AUX/ADC headers can be used to read contacts. In a typical configuration (1 x TSic sensor + 1 x tank sensor + 1 x pressure sensor), one pin is free to be used as configurable contact input
2: Will require internet access to obtain time from SNTP server because ito has no clock chip.
3: Available resolution depends on the pump. ULKA E5 series recommended, e.g. EP5.
4: leva! supports flow meters up to 9999 impulses per liter that work with 5V supply voltage and have an open collector ouptut with pull-up. Recommended: Digmesa 974-xxxx
5: leva! supports ratiometric sensors of type "gage" (relative-to-ambient measurements) that work with 5V supply voltage and have a range between 10 - 40bar (145 - 580psi)
6: A paddle is a lever-operated linear 10K potentiometer
7: ito's serial port at the AUX header can only be used for firmware updates. leva! will not transmit live data over it. It uses the AUX port for sensors.
 
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