sipo.h

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//   Copyright 2016-2023 Jean-Francois Poilpret
//
//   Licensed under the Apache License, Version 2.0 (the "License");
//   you may not use this file except in compliance with the License.
//   You may obtain a copy of the License at
//
//       http://www.apache.org/licenses/LICENSE-2.0
//
//   Unless required by applicable law or agreed to in writing, software
//   distributed under the License is distributed on an "AS IS" BASIS,
//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//   See the License for the specific language governing permissions and
//   limitations under the License.
 
 
#ifndef SIPO_HH
#define SIPO_HH
 
#include "../gpio.h"
 
namespace devices
{
    template<board::DigitalPin CLOCK_, board::DigitalPin LATCH_, board::DigitalPin DATA_> class SIPO
    {
    public:
        static constexpr const board::DigitalPin CLOCK = CLOCK_;
        static constexpr const board::DigitalPin LATCH = LATCH_;
        static constexpr const board::DigitalPin DATA = DATA_;
 
        SIPO(const SIPO&) = delete;
        SIPO& operator=(const SIPO&) = delete;
        
        SIPO() = default;
 
        void init()
        {
            clock_.set_mode(gpio::PinMode::OUTPUT, false);
            latch_.set_mode(gpio::PinMode::OUTPUT, true);
            data_.set_mode(gpio::PinMode::OUTPUT, false);
        }
 
        template<typename T> void output(T data)
        {
            uint8_t* pdata = (uint8_t*) data;
            latch_.clear();
            for (uint8_t i = 0; i < sizeof(T); ++i) bit_bang_data(pdata[i]);
            latch_.set();
        }
 
        // Specialized output for most common types
        void output(uint8_t data) INLINE
        {
            latch_.clear();
            bit_bang_data(data);
            latch_.set();
        }
 
        void output(uint16_t data) INLINE
        {
            latch_.clear();
            bit_bang_data(bits::HIGH_BYTE(data));
            bit_bang_data(bits::LOW_BYTE(data));
            latch_.set();
        }
 
    private:
        void bit_bang_data(uint8_t data)
        {
            // Start with MSB
            uint8_t mask = 0x80;
            do
            {
                if (data & mask)
                    data_.set();
                else
                    data_.clear();
                clock_.set();
                mask >>= 1;
                clock_.clear();
            } while (mask);
        }
 
        gpio::FAST_PIN<CLOCK> clock_;
        gpio::FAST_PIN<LATCH> latch_;
        gpio::FAST_PIN<DATA> data_;
    };
}
 
#endif /* SIPO_HH */