Expand description
Driver in Rust for the KC11B04 4-button analog keypad.
A 3-pin module using a voltage divider circuit and analog pin to sense a key press.
Wiring notes
The voltage on the VCC
pin should correspond with the reference voltage (maximum value) your ADC is configured to read.
For example the default on an Arduino Uno is that it matches the operating voltage of 5V.
But the ADC can be configured to use an external reference with the AREF
pin. In this case VCC
should match AREF
.
Example
use kc11b04::{Key, KC11B04, MAP_10BIT};
let mut adc = /* Configure your ADC using its HAL */
let mut ad_pin = /* Set the pin connected to AD as analog input */
// Create the keypad driver. Taking ownership of the pin,
// providing a map that matches the resolution of your ADC.
let mut keypad = KC11B04::new(ad_pin, MAP_10BIT);
// Somewhere within loop { }
// Read current key state.
match keypad
.key_state(&mut adc)
.expect("Problem reading ADC channel")
{
Some(Key::K4) => { /* K4 key being pressed */ }
Some(Key::K3) => { /* K3 key being pressed */ }
Some(Key::K2) => { /* K2 key being pressed */ }
Some(Key::K1) => { /* K1 key being pressed */ }
None => { /* Either nothing, or multiple keys pressed */ }
}
MSRV & Stability
This crate compiles on stable Rust 1.60
and up. It might still work on older rust versions,
but this isn’t ensured. Upgrading the MSRV is considered SemVer breaking.
Re-exports
pub use mapping::KeyMap;
Modules
- This module maps keys to their expected ADC readings.
Macros
- Defines a
KeyMap
based on the max reading of the ADC and optional margin factor.
Structs
- KC11B04 analog keypad driver. Constructed with
KC11B04::new
.
Enums
- A named key on the KC11B04 module.
Constants
KeyMap
for 8bit ADCs with a maximum reading of255
.KeyMap
for 10bit ADCs with a maximum reading of1023
.KeyMap
for 12bit ADCs with a maximum reading of4095
.KeyMap
for signed 12bit ADCs with a maximum positive reading of2047
.KeyMap
for 16bit ADCs with a maximum reading of65535
.KeyMap
for signed 16bit ADCs with a maximum positive reading of32767
.KeyMap
for 24bit ADCs with a maximum reading of16777215
.