--------------------------------------------------------------------------------------------------- |-- Module : System.Hardware.Arduino.Parts.Servo-- Copyright : (c) Levent Erkok-- License : BSD3-- Maintainer : erkokl@gmail.com-- Stability : experimental---- Abstractions for servo motors. See "System.Hardware.Arduino.SamplePrograms.Servo" for-- example uses.-------------------------------------------------------------------------------------------------{-# LANGUAGE NamedFieldPuns #-}moduleSystem.Hardware.Arduino.Parts.Servo(-- * Attaching a servo motor on a pinServo ,attach -- * Setting servo position,setAngle )whereimportControl.Monad(when)importData.Bits(shiftR,(.&.))importData.Maybe(fromMaybe)importSystem.Hardware.Arduino importSystem.Hardware.Arduino.Comm importSystem.Hardware.Arduino.Data -- | A servo motor. Note that this type is abstract, use 'attach' to-- create an instance.dataServo =Servo {Servo -> IPin
servoPin ::IPin -- ^ The internal-pin that controls the servo,Servo -> Int
minPulse ::Int-- ^ Pulse-width (microseconds) for the minumum (0-degree) angle.,Servo -> Int
maxPulse ::Int-- ^ Pulse-width (microseconds) for the maximum (typically 180-degree) angle.}-- | Create a servo motor instance. The default values for the min/max angle pulse-widths, while typical,-- may need to be adjusted based on the specs of the actual servo motor. Check the data-sheet for your-- servo to find the proper values. The default values of @544@ and @2400@ microseconds are typical, so you might-- want to start by passing 'Nothing' for both parameters and adjusting as necessary.attach ::Pin -- ^ Pin controlling the servo. Should be a pin that supports SERVO mode.->MaybeInt-- ^ Pulse-width (in microseconds) for the minumum 0-degree angle. Default: @544@.->MaybeInt-- ^ Pulse-width (in microseconds) for the maximum, typically 180-degree, angle. Default: @2400@.->Arduino Servo attach :: Pin -> Maybe Int -> Maybe Int -> Arduino Servo
attach Pin
p Maybe Int
mbMin Maybe Int
mbMax |JustInt
m <-Maybe Int
mbMin ,Int
m forall a. Ord a => a -> a -> Bool
<Int
0=forall a. String -> [String] -> Arduino a
die String
"Servo.attach: minimum pulse width must be positive"[String
"Received: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
m ]|JustInt
m <-Maybe Int
mbMax ,Int
m forall a. Ord a => a -> a -> Bool
<Int
0=forall a. String -> [String] -> Arduino a
die String
"Servo.attach: maximum pulse width must be positive"[String
"Received: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
m ]|Bool
True=doletminPulse :: Int
minPulse =forall a. a -> Maybe a -> a
fromMaybeInt
544Maybe Int
mbMin maxPulse :: Int
maxPulse =forall a. a -> Maybe a -> a
fromMaybeInt
2400Maybe Int
mbMax String -> Arduino ()
debug forall a b. (a -> b) -> a -> b
$String
"Attaching servo on pin: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showPin
p forall a. [a] -> [a] -> [a]
++String
" with parameters: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
show(Int
minPulse ,Int
maxPulse )forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
when(Int
minPulse forall a. Ord a => a -> a -> Bool
>=Int
maxPulse )forall a b. (a -> b) -> a -> b
$forall a. String -> [String] -> Arduino a
die String
"Servo.attach: min pulse duration must be less than max pulse duration"[String
"Received min-pulse: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
minPulse ,String
"Received max-pulse: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
maxPulse ]Pin -> PinMode -> Arduino ()
setPinMode Pin
p PinMode
SERVO (IPin
ip ,PinData
_)<-String -> Pin -> PinMode -> Arduino (IPin, PinData)
convertAndCheckPin String
"Servo.attach"Pin
p PinMode
SERVO forall (m :: * -> *) a. Monad m => a -> m a
returnServo {servoPin :: IPin
servoPin =IPin
ip ,minPulse :: Int
minPulse =forall a. a -> Maybe a -> a
fromMaybeInt
544Maybe Int
mbMin ,maxPulse :: Int
maxPulse =forall a. a -> Maybe a -> a
fromMaybeInt
2400Maybe Int
mbMax }-- | Set the angle of the servo. The argument should be a number between 0 and 180,-- indicating the desired angle setting in degrees.setAngle ::Servo ->Int->Arduino ()setAngle :: Servo -> Int -> Arduino ()
setAngle Servo {IPin
servoPin :: IPin
servoPin :: Servo -> IPin
servoPin ,Int
minPulse :: Int
minPulse :: Servo -> Int
minPulse ,Int
maxPulse :: Int
maxPulse :: Servo -> Int
maxPulse }Int
angle |Int
angle forall a. Ord a => a -> a -> Bool
<Int
0Bool -> Bool -> Bool
||Int
angle forall a. Ord a => a -> a -> Bool
>Int
180=forall a. String -> [String] -> Arduino a
die String
"Servo.setAngle: angle must be between 0 and 180."[String
"Received: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
angle ]|Bool
True=doletduration :: Int
duration =Int
minPulse forall a. Num a => a -> a -> a
+((Int
maxPulse forall a. Num a => a -> a -> a
-Int
minPulse )forall a. Num a => a -> a -> a
*Int
angle )forall a. Integral a => a -> a -> a
`div`Int
180String -> Arduino ()
debug forall a b. (a -> b) -> a -> b
$String
"Setting servo on pin: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showIPin
servoPin forall a. [a] -> [a] -> [a]
++String
" "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
angle forall a. [a] -> [a] -> [a]
++String
" degrees, via a pulse of "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
duration forall a. [a] -> [a] -> [a]
++String
" microseconds."-- In arduino, the most we can send is 16383; not that a servo should need such a large value, but-- just in caseforall (f :: * -> *). Applicative f => Bool -> f () -> f ()
when(Int
duration forall a. Ord a => a -> a -> Bool
>=Int
16383)forall a b. (a -> b) -> a -> b
$forall a. String -> [String] -> Arduino a
die String
"Servo.setAngle angle setting: out-of-range."[String
"Servo pin : "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showIPin
servoPin ,String
"Angle required : "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
angle ,String
"Min pulse duration: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
minPulse ,String
"Max pulse duration: "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
maxPulse ,String
"Duration needed : "forall a. [a] -> [a] -> [a]
++forall a. Show a => a -> String
showInt
duration ,String
"Exceeds max value : 16383"]letmsb :: Word8
msb =forall a b. (Integral a, Num b) => a -> b
fromIntegralforall a b. (a -> b) -> a -> b
$(Int
duration forall a. Bits a => a -> Int -> a
`shiftR`Int
7)forall a. Bits a => a -> a -> a
.&.Int
0x7flsb :: Word8
lsb =forall a b. (Integral a, Num b) => a -> b
fromIntegralforall a b. (a -> b) -> a -> b
$Int
duration forall a. Bits a => a -> a -> a
.&.Int
0x7fRequest -> Arduino ()
send forall a b. (a -> b) -> a -> b
$IPin -> Word8 -> Word8 -> Request
AnalogPinWrite IPin
servoPin Word8
lsb Word8
msb