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library Servo added, but now the TIM1_CC interrupt needs to be enabled by hand in stm8s_it.h
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‎docs/api/Servo.md‎

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# Servo Library
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This library can control a great number of servos. It makes careful use
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of timers: the library can control 12 servos using only 1 timer.
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Derived from the Arduino Servo library v1.8.0.
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This library has a slightly diffent user interface than the usual singleton
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libraries. This allows for handling more than one servo per Sketch but it
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requires some more attention when porting an existing sketch from C++ to C.
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Each Servo instance is identified by a channel-ID. In order to match the C++
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class constructor syntax it is defined as a type `Servo`.
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This channel-ID is used as a file-descriptor-like value and need to be
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passed to all API functions except for `Servo_attach()`. This function
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claimes the next free channel number.
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## Example
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Read a potentiometer on analog input 0 and set a servo pulse length between
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1000us and 2023us:
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```c
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#include <Arduino.h>
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#include <Servo.h>
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Servo myservo; // just a simple unsigned char to hold the channel-ID
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int val; // variable to read the value from the analog pin
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void setup() {
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myservo = Servo_attach(9); // attaches the servo on pin 9, returns channel-ID
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}
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void loop() {
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val = analogRead(0); // reads the value of the potentiometer
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Servo_write(myservo, val+1000);// sets the servo position
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delay(15);
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}
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```
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Original Arduino C++-Sytax:
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```c
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#include <Servo.h>
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Servo myservo; // create servo object to control a servo
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int val; // variable to read the value from the analog pin
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void setup() {
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myservo.attach(9); // attaches the servo on pin 9 to the servo object
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}
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void loop() {
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val = analogRead(0); // reads the value of the potentiometer
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myservo.write(val+1000); // sets the servo position
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delay(15);
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}
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```
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## API
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data type `Servo`: A type definition for a simple unsigned char to hold the
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channel number returned my `Servo_attach()`. Needed for every servo. Syntax
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identical to the Arduino class constructor.
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Arduino syntax |sduino syntax
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-------------------- |---------------------
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`Servo myservo;` |`Servo myservo;`
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`myservo.attach(pin);` |`myservo = Servo_attach(pin);`
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`myservo.attach(pin,min,max);` |`Servo_attach_minmax(pin,min,max);`
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`myservo.detach();` |`Servo_detach(byte channel);`
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`myservo.write(val);` |`Servo_write(myservo, val);`
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`myservo.writeMicroseconds(val);`|`Servo_writeMicroseconds(myservo, val);`
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`val = myservo.read();` |`val = Servo_read(myservo);`
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`val = myservo.readMicroseconds();`|`val = Servo_readMicroseconds(myservo);`
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`myservo.attached()` |`Servo_attached(myservo);`
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`uint8_t Servo_attach(int pin);`
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attach the given pin to the next free channel, sets pinMode, returns channel
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number or 0 if failure.
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`uint8_t Servo_attach_minmax(int pin, int min, int max);`
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as above but also sets min and max values for writes.
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`void Servo_detach(byte channel);`
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`void Servo_write(byte channel, int value);` if value is < 200 it is treated
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as an angle and scaled according the minimum and maximum pulsewidth defined
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using the attach() function earlier, otherwise as pulse width in
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microseconds, unscaled.
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`void Servo_writeMicroseconds(byte channel, int value);`
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Write pulse width in microseconds, unscaled.
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`int Servo_read(byte channel);`
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returns current pulse width as an angle between 0 and 180 degrees.
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`int Servo_readMicroseconds(byte channel);`
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returns current pulse width in microseconds for this servo (was read_us() in
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first Arduino release).
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`bool Servo_attached(byte channel);`
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return true if this servo is attached, otherwise false .
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## Relationship between PWM/analog output and Servo output
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It is not possible to use a timer for PWM and the Servo Library at the same
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time. Since this library currently uses timer1, the PWM function
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(`analogWrite()`) is disabled for the pins connected to timer1 (for the
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STM8S103 this is pin PC3 and PC4 or digital pin 5 and 6).
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Pins connected to timer2 (PA3, PD3, PD4, digital pin 2,12,13) are still
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usable for PWM output.
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## Possible improvements
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### A more sophisticated pseudo-OO API
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Define a set of preprocessor macros that more OO-like definitions like this
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become possible:
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Current syntax |OO-like syntax |Arduino syntax
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-------------------- |--------------------- |--------------
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myservo = Servo_attach(pin); |myservo_attach(pin); |myservo.attach(pin);
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Servo_write(myservo, val); |myservo_write(val); |myservo_write(val);
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val = Servo_read(myservo); |val = myservo_read(); |val = myservo_read();
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### Optimizing the handle_interrupts() function
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SDCC compiles this function very inefficiently. The code size is around 500
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Bytes, and it is executed as part of the CC interrupt routine. Expected CPU
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load for a full servo group of 12 servos is approx. 2%.
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(Calculated for 16MHz CPU clock, 13 interrupts every 20ms = 650
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interrupts/sec, approx. 500 clock cycles each)
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### Using more than one CC channel per timer
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it might be possible to use all capture+compare (CC) channels of one timer
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at the same time, attaching one servo group to each CC-channel. This way it
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would be possible to serve up to 48 servos using the four CC-channels of
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timer TIM1. Monitoring the repetion period might become a little complex, as
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it must be ensured that all servos on all channels have finshed before.
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‎docs/index.md‎

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[API description](api/Stepper.html)
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### Servo
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This library can control a great number of servos. It makes careful use
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of timers: the library can control 12 servos using only 1 timer.
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[API description](api/Servo.html)
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## Current status and to-do list
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LiquidCrystal (for text LCD based on the HD44780 controller)
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PCD8544 (for Nokia 5110 type displays)
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[Stepper](api/Stepper.html) (multi-instance design for more than one stepper at a time)
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[Servo](api/Servo.html) (multi-instance design for more than one servo at a time)
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#### implemented and partly working
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Wire/I2C

‎sduino/hardware/sduino/stm8/libraries/Servo/README.adoc‎

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= Servo Library for Arduino =
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This library allows an Arduino board to control RC (hobby) servo motors.
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For more information about this library please visit us at
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http://www.arduino.cc/en/Reference/Servo
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== License ==
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Copyright (c) 2013 Arduino LLC. All right reserved.
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Copyright (c) 2009 Michael Margolis. All right reserved.
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

‎sduino/hardware/sduino/stm8/libraries/Servo/examples/Knob/Knob.c‎

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/*
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Controlling a servo position using a potentiometer (variable resistor)
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by Michal Rinott <http://people.interaction-ivrea.it/m.rinott>
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modified on 8 Nov 2013
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by Scott Fitzgerald
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http://www.arduino.cc/en/Tutorial/Knob
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modified to C syntax on 30 Jan 2017 for use with the sdunio environment
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by Michael Mayer
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*/
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#include <Arduino.h>
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#include <Servo.h>
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Servo myservo; // create servo object to control a servo
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int potpin = 0; // analog pin used to connect the potentiometer
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int val; // variable to read the value from the analog pin
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void setup() {
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myservo = Servo_attach(9); // attaches the servo on pin 9 to the servo object
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}
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#define myservo_write(V) Servo_write(myservo,V)
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void loop() {
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val = analogRead(potpin); // reads the value of the potentiometer (value between 0 and 1023)
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val = map(val, 0, 1023, 0, 180); // scale it to use it with the servo (value between 0 and 180)
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// Servo_write(myservo,val); // sets the servo position according to the scaled value
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myservo_write(val); // sets the servo position according to the scaled value
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delay(15); // waits for the servo to get there
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}

‎sduino/hardware/sduino/stm8/libraries/Servo/examples/Knob/Makefile‎

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BOARD_TAG = stm8sblue
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include ../../../../../../../sduino.mk

‎sduino/hardware/sduino/stm8/libraries/Servo/examples/Sweep/Makefile‎

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BOARD_TAG = stm8sblue
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include ../../../../../../../sduino.mk

‎sduino/hardware/sduino/stm8/libraries/Servo/examples/Sweep/Sweep.c‎

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/* Sweep
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by BARRAGAN <http://barraganstudio.com>
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This example code is in the public domain.
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modified 8 Nov 2013
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by Scott Fitzgerald
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http://www.arduino.cc/en/Tutorial/Sweep
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modified to C syntax on 30 Jan 2017 for use with the sdunio environment
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by Michael Mayer
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*/
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#include <Arduino.h>
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#include <Servo.h>
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Servo myservo; // create servo object to control a servo
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// twelve servo objects can be created on most boards
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int pos = 0; // variable to store the servo position
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void setup() {
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myservo = Servo_attach(9); // attaches the servo on pin 9 to the servo object
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}
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void loop() {
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for (pos = 0; pos <= 180; pos += 1) { // goes from 0 degrees to 180 degrees
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// in steps of 1 degree
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Servo_write(myservo,pos); // tell servo to go to position in variable 'pos'
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delay(15); // waits 15ms for the servo to reach the position
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}
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for (pos = 180; pos >= 0; pos -= 1) { // goes from 180 degrees to 0 degrees
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Servo_write(myservo,pos); // tell servo to go to position in variable 'pos'
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delay(15); // waits 15ms for the servo to reach the position
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}
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}
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‎sduino/hardware/sduino/stm8/libraries/Servo/keywords.txt‎

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#######################################
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# Syntax Coloring Map Servo
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#######################################
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#######################################
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# Datatypes (KEYWORD1)
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#######################################
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Servo KEYWORD1 Servo
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#######################################
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# Methods and Functions (KEYWORD2)
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#######################################
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attach KEYWORD2
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detach KEYWORD2
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write KEYWORD2
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read KEYWORD2
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attached KEYWORD2
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writeMicroseconds KEYWORD2
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readMicroseconds KEYWORD2
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#######################################
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# Constants (LITERAL1)
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#######################################

‎sduino/hardware/sduino/stm8/libraries/Servo/library.properties‎

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name=Servo
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version=1.1.2
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author=Michael Margolis, Arduino
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maintainer=Arduino <[email protected]>
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sentence=Allows Arduino/Genuino boards to control a variety of servo motors.
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paragraph=This library can control a great number of servos.<br />It makes careful use of timers: the library can control 12 servos using only 1 timer.<br />On the Arduino Due you can control up to 60 servos.<br />
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category=Device Control
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url=http://www.arduino.cc/en/Reference/Servo
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architectures=stm8

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