com: A spi implementation and a spi bit-banging added
This commit is contained in:
Christos Houtouridis
parent
49b219ef25
commit
d127713711
331
include/utl/com/spi.h
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331
include/utl/com/spi.h
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/*!
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* \file /utl/com/spi.h
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* \brief An Abstract base class interface for the spi bus
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*
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* Copyright (C) 2018 Christos Choutouridis
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as
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* published by the Free Software Foundation, either version 3
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* of the License, or (at your option) any later version.
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*
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* This program 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
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#ifndef _utl_com_spi_h__
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#define _utl_com_spi_h__
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#include <utl/impl/impl.h>
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#include <utl/helper/crtp.h>
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#include <utl/meta/sfinae.h>
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namespace utl {
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/*!
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* \ingroup Communication
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* \brief Abstract base class for spi bus
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*/
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//!@{
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namespace spi {
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/*!
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* SPI implementation bit order
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*/
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enum class bitOrder {
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LSB_First =0x01, //!< Most significant first
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MSB_First =0x80 //!< Less significant first
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};
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/*!
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* SPI implementation Clock Polarity
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*/
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enum class cpol {
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LOW =0, //!< LOW
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HIGH //!< HIGH
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};
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/*!
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* SPI implementation Clock Phase
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*/
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enum class cpha {
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LOW =0, //!< LOW
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HIGH //!< HIGH
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};
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}
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/*!
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* Template base class for SPI communication interface using CRTP
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* This class force a common interface for SPI communication
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* protocol implementations.
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* \param impl_t The CRTP type (the derived/implementation class typename).
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*/
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template <typename impl_t>
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class spi_i {
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_CRTP_IMPL(impl_t); //! \brief Syntactic sugar to CRTP casting
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public:
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using type = spi_i<impl_t>; //!< Export type as identity meta-function
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/*!
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* \name Object lifetime
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*/
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//!@{
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protected:
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spi_i () = default; //!< Allow constructor from derived only
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~spi_i () = default; //!< Allow destructor from derived only
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spi_i (const type&) = delete; //!< No copies
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spi_i& operator= (const spi_i&) = delete;
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//!@}
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/*!
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* \name Implementation requirements
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* \note
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* In order for the implementation to have the following as private members
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* it also need to declare this class as friend
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*/
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//! @{
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private:
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uint32_t _clock () const { return impl()._clock (); } //!< clock frequency of the bus [Hz]
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void _clock (uint32_t c) { impl()._clock (c); } //!< set clock frequency of the bus [Hz]
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byte_t _tx_data (byte_t b) { return impl()._tx_data (b); } //!< Transmit a byte on the bus and return the response
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//! @}
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/*!
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* \name Get/Set functions provided by the interface
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*/
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//!@{
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public:
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uint32_t clock () const { return _clock (); } //!< \return clock frequency of the bus
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void clock (uint32_t c) { _clock (c); } //!< \brief set clock frequency of the bus
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//!@}
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/*!
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* \name I/O functions provided by the interface
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*/
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//!@{
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public:
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/*!
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* Transmit a byte to spi bus and return the response
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*/
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byte_t tx_data (byte_t out) {
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return _tx_data (out);
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}
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/*!
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* \brief
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* Transmit a number of bytes to the spi bus and read the response.
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* \param out Pointer to data to send to the bus
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* \param in Pointer to buffer to store the data from the bus
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* \param n The number of bytes to transmit/receive
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* \return The number of bytes.
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*/
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size_t tx_data (const byte_t *out, byte_t *in, size_t n);
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/*!
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* Receive a byte from spi bus while transmitting 0xFF
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*/
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byte_t rx_data () {
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return _tx_data(0xFF);
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}
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/*!
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* \brief
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* Receive a number of bytes from the spi bus while transmitting 0xFFs.
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* \param in Pointer to buffer to store the data
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* \param n The number of bytes to read
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* \return The number of received bytes.
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*/
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size_t rx_data (byte_t *in, size_t n);
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//!@}
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};
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/*!
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* \brief
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* Transmit a number of bytes to the spi bus and read the response.
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* \param out Pointer to data to send to the bus
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* \param in Pointer to buffer to store the data from the bus
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* \param n The number of bytes to transmit/receive
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* \return The number of bytes.
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*/
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template<typename _I>
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size_t spi_i<_I>::tx_data (const byte_t *out, byte_t *in, size_t n) {
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for (size_t nn {n} ; nn ; --nn)
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*in++ = _tx_data (*out++);
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return n;
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}
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/*!
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* \brief
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* Receive a number of bytes from the spi bus while transmitting 0xFFs.
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* \param in Pointer to buffer to store the data
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* \param n The number of bytes to read
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* \return The number of received bytes.
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*/
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template<typename _I>
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size_t spi_i<_I>::rx_data (byte_t *in, size_t n) {
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for (size_t nn {n} ; nn ; --nn)
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*in++ = _tx_data (0xFF);
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return n;
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}
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/*!
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* \brief
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* A virtual base class implementation
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* \param none
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*/
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template <>
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class spi_i <virtual_tag> {
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public:
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using type = spi_i<virtual_tag>; //!< Export type as identity meta-function
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/*!
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* \name Object lifetime
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*/
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//!@{
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protected:
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spi_i () = default; //!< Allow constructor from derived only
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spi_i (const type&) = delete; //!< No copies
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type& operator= (const type&) = delete;
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public:
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virtual ~spi_i () = default; //!< Virtual default destructor
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//!@}
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/*!
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* \name Implementation requirements
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*/
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//! @{
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private:
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virtual uint32_t _clock () const =0; //!< Read the clock frequency of the bus
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virtual void _clock (uint32_t) =0; //!< Set the clock frequency of the bus
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virtual byte_t _tx_data (byte_t) =0; //!< Transmit a byte on the bus and return the response
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//! @}
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/*!
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* \name Get/Set functions provided by the interface
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*/
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//!@{
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public:
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uint32_t clock () const { return _clock (); } //!< \return clock frequency of the bus
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void clock (uint32_t c) { _clock (c); } //!< \brief set clock frequency of the bus
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//!@}
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/*!
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* \name I/O functions provided by the interface
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*/
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//!@{
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public:
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/*!
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* Transmit a byte to spi bus and return the response
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*/
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byte_t tx_data (byte_t out) {
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return _tx_data (out);
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}
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/*!
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* \brief
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* Transmit a number of bytes to the spi bus and read the response.
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* \param out Pointer to data to send to the bus
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* \param in Pointer to buffer to store the data from the bus
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* \param n The number of bytes to transmit/receive
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* \return The number of bytes.
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*/
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size_t tx_data (const byte_t *out, byte_t *in, size_t n);
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/*!
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* Receive a byte from spi bus while transmitting 0xFF
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*/
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byte_t rx_data () {
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return _tx_data (0xFF);
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}
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/*!
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* \brief
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* Receive a number of bytes from the spi bus while transmitting 0xFFs.
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* \param in Pointer to buffer to store the data
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* \param n The number of bytes to read
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* \return The number of received bytes.
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*/
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size_t rx_data (byte_t *in, size_t n);
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//!@}
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};
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/*!
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* \brief
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* Transmit a number of bytes to the spi bus and read the response.
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* \param out Pointer to data to send to the bus
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* \param in Pointer to buffer to store the data from the bus
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* \param n The number of bytes to transmit/receive
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* \return The number of bytes.
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*/
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size_t spi_i<virtual_tag>::tx_data (const byte_t *out, byte_t *in, size_t n) {
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for (size_t nn {n} ; nn ; --nn)
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*in++ = _tx_data (*out++);
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return n;
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}
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/*!
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* \brief
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* Receive a number of bytes from the spi bus while transmitting 0xFFs.
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* \param in Pointer to buffer to store the data
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* \param n The number of bytes to read
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* \return The number of received bytes.
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*/
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size_t spi_i<virtual_tag>::rx_data (byte_t *in, size_t n) {
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for (size_t nn {n} ; nn ; --nn)
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*in++ = _tx_data (0xFF);
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return n;
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}
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#if defined _utl_have_concepts
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/*!
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* i2c interface concept
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*/
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template <typename T>
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concept bool spi_c = requires (T t, const T ct, typename T::Sequence s) {
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// Object type
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requires not_<std::is_copy_constructible<T>::value>::value;
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requires not_<std::is_copy_assignable<T>::value>::value;
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// Methods
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{ct.clock()} -> uint32_t;
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{t.clock(0)} -> void;
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{t.tx_data(1)} -> byte_t;
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{t.rx_data()} -> byte_t;
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};
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#else
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namespace spi_i_details {
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using std::declval;
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template <class _Tp> using try_cclock_t= decltype (declval<const _Tp>().clock());
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template <class _Tp> using try_clock_t = decltype (declval<_Tp>().clock(declval<uint32_t>()));
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template <class _Tp> using try_tx_t = decltype (declval<_Tp>().tx_data(declval<byte_t>()));
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template <class _Tp> using try_rx_t = decltype (declval<_Tp>().rx_data());
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//! Primary template to catch any non SPI interface types
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template <typename _Tp, typename =void>
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struct is_spi_ : false_ {};
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//! template to catch a proper SPI interface type
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template <typename _Tp>
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struct is_spi_ <
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_Tp,
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void_t <
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use_if_same_t <try_cclock_t<_Tp>, uint32_t>,
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use_if_same_t <try_clock_t<_Tp>, void>,
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use_if_same_t <try_tx_t<_Tp>, byte_t>,
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use_if_same_t <try_rx_t<_Tp>, byte_t>
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>
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> : true_ {};
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}
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/*!
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* Value meta-programming function for SPI interface checking
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* \param _Tp Type to check
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* \return True if _Tp is a spi interface
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*/
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template <typename _Tp>
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constexpr bool spi_c = spi_i_details::is_spi_<_Tp>::value;
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#endif
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//!@}
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} // namespace utl
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#endif /* #ifndef _utl_com_spi_h__ */
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286
include/utl/com/spi_bb.h
Normal file
286
include/utl/com/spi_bb.h
Normal file
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/*!
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* \file utl/com/spi_bb.h
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* \brief A bit banking implementation of spi bus inherited from
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* spi_i base class.
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*
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* Copyright (C) 2018 Christos Choutouridis
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*
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* This program is free software: you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as
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* published by the Free Software Foundation, either version 3
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* of the License, or (at your option) any later version.
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*
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* This program 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
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* GNU Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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*/
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#ifndef __utl_com_spi_bb_h__
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#define __utl_com_spi_bb_h__
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#include <utl/impl/impl.h>
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#include <utl/helper/crtp.h>
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#include <utl/meta/sfinae.h>
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#include <utl/com/spi.h>
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namespace utl {
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/*!
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* \ingroup Communication
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* \brief A bit banking implementation of spi bus
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* inherited from \ref spi_i base class.
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* \sa spi_i
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*/
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//!@{
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/*!
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* \brief
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* SPI bit banking interface template class using CRTP.
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* Using the private interface we provide the interface from
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* spi_i<impl_t>
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*
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* \param impl_t The CRTP type (the derived/implementation class typename).
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* \param CPOL Clock polarity
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* \param CPHA Clock phase
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* \param BitOrder Data transfer bit order
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*/
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template <typename impl_t,
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spi::cpol CPOL,
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spi::cpha CPHA,
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spi::bitOrder BitOrder =spi::bitOrder::MSB_First>
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class spi_bb_i : public spi_i<spi_bb_i<impl_t, CPOL, CPHA, BitOrder>> {
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_CRTP_IMPL(impl_t); //! \brief Syntactic sugar to CRTP casting
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||||||
|
friend spi_i<spi_bb_i<impl_t, CPOL, CPHA, BitOrder>>;
|
||||||
|
public:
|
||||||
|
using type = spi_bb_i<impl_t, CPOL, CPHA, BitOrder>; //!< Export type as identity meta-function
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \name Object lifetime
|
||||||
|
*/
|
||||||
|
//!@{
|
||||||
|
protected:
|
||||||
|
~spi_bb_i () = default; //!< A default destructor, allow destructor from derived only
|
||||||
|
//! \brief A default constructor
|
||||||
|
spi_bb_i (uint32_t clk =1000000) noexcept
|
||||||
|
: nsec_ {1000000000/(2*clk)} {
|
||||||
|
}
|
||||||
|
//!@}
|
||||||
|
|
||||||
|
private:
|
||||||
|
//! \name SPI implementation specific functions
|
||||||
|
//!@{
|
||||||
|
template <spi::cpol C =CPOL> constexpr bool clkHigh () { return !static_cast<bool>(C); }
|
||||||
|
template <spi::cpol C =CPOL> constexpr bool clkLow () { return static_cast<bool>(C); }
|
||||||
|
template <spi::bitOrder B =BitOrder> constexpr
|
||||||
|
use_if_t <(B == spi::bitOrder::LSB_First), void> shift (byte_t& b) { b <<=1; }
|
||||||
|
template <spi::bitOrder B =BitOrder> constexpr
|
||||||
|
use_if_t <(B == spi::bitOrder::MSB_First), void> shift (byte_t& b) { b >>=1; }
|
||||||
|
//!}
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \name Implementation requirements
|
||||||
|
* \note
|
||||||
|
* In order for the implementation to have the following as private members
|
||||||
|
* it also need to declare this class as friend
|
||||||
|
*/
|
||||||
|
//!@{
|
||||||
|
private:
|
||||||
|
void MOSI (bool st) { impl().MOSI(st); } //!< Implementers's MOSI pin function
|
||||||
|
bool MISO () { return impl().MISO(); } //!< Implementers's MISO pin function
|
||||||
|
void SCLK (bool st) { impl().SCLK (st); } //!< Implementers's SCLK pin function
|
||||||
|
void delay (uint32_t nsec) { impl().delay (nsec); } //!< Implementers's half period delay function
|
||||||
|
//!@}
|
||||||
|
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \name Implementation of base requirements
|
||||||
|
*/
|
||||||
|
//!@{
|
||||||
|
private:
|
||||||
|
uint32_t _clock () const { return 1000000000/(2*nsec_); }
|
||||||
|
void _clock (uint32_t c) { nsec_ = 1000000000/(2*c); }
|
||||||
|
byte_t _tx_data (byte_t out) { return _tx_data_impl (out); }
|
||||||
|
|
||||||
|
template <spi::cpha C =CPHA>
|
||||||
|
use_if_t <(C == spi::cpha::LOW), byte_t> _tx_data_impl (byte_t out);
|
||||||
|
template <spi::cpha C =CPHA>
|
||||||
|
use_if_t <(C == spi::cpha::HIGH), byte_t> _tx_data_impl (byte_t out);
|
||||||
|
|
||||||
|
uint32_t nsec_; //!< half period of SPI bus
|
||||||
|
//!@}
|
||||||
|
};
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief
|
||||||
|
* _tx_data implementation for CPHA == LOW
|
||||||
|
* Out at preceding clock trailing edge, In at leading clock edge
|
||||||
|
* \param out The byte to send to SPI bus
|
||||||
|
* \return The byte read from the bus
|
||||||
|
*/
|
||||||
|
template <typename impl_t, spi::cpol CPOL, spi::cpha CPHA, spi::bitOrder BitOrder>
|
||||||
|
template <spi::cpha C>
|
||||||
|
use_if_t <(C == spi::cpha::LOW), byte_t>
|
||||||
|
spi_bb_i<impl_t, CPOL, CPHA, BitOrder>::_tx_data_impl (byte_t out) {
|
||||||
|
byte_t in {};
|
||||||
|
SCLK (clkLow());
|
||||||
|
for (uint8_t bit {static_cast<uint8_t>(BitOrder)} ; bit ; shift (bit)) {
|
||||||
|
MOSI (out & bit); // Out at preceding clock trailing edge
|
||||||
|
delay (nsec_); // Half cycle delay
|
||||||
|
SCLK (clkHigh()); // Leading edge
|
||||||
|
in |= (MISO ()) ? bit : 0; // In at leading clock edge
|
||||||
|
delay (nsec_); // Half cycle delay
|
||||||
|
SCLK (clkLow()); // Trailing edge
|
||||||
|
}
|
||||||
|
return in;
|
||||||
|
}
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief
|
||||||
|
* _tx_data implementation CPHA == HIGH
|
||||||
|
* Out at leading clock edge, In at trailing clock edge
|
||||||
|
* \param out The byte to send to SPI bus
|
||||||
|
* \return The byte read from the bus
|
||||||
|
*/
|
||||||
|
template <typename impl_t, spi::cpol CPOL, spi::cpha CPHA, spi::bitOrder BitOrder>
|
||||||
|
template <spi::cpha C>
|
||||||
|
use_if_t <(C == spi::cpha::HIGH), byte_t>
|
||||||
|
spi_bb_i<impl_t, CPOL, CPHA, BitOrder>::_tx_data_impl (byte_t out) {
|
||||||
|
byte_t in {};
|
||||||
|
SCLK (clkLow());
|
||||||
|
for (uint8_t bit {static_cast<uint8_t>(BitOrder)} ; bit ; shift (bit)) {
|
||||||
|
delay (nsec_); // Half cycle delay
|
||||||
|
SCLK (clkHigh()); // Leading edge
|
||||||
|
MOSI (out & bit); // Out at leading clock edge
|
||||||
|
delay (nsec_); // Half cycle delay
|
||||||
|
SCLK (clkLow()); // Trailing edge
|
||||||
|
in |= (MISO ()) ? bit : 0; // In at trailing clock edge
|
||||||
|
}
|
||||||
|
return in;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief
|
||||||
|
* A virtual base class interface specialization.
|
||||||
|
* Using the private virtual interface we provide the interface from
|
||||||
|
* spi_i<virtual_tag>
|
||||||
|
* \param impl_t = virtual_tag
|
||||||
|
* \param CPOL Clock polarity
|
||||||
|
* \param CPHA Clock phase
|
||||||
|
* \param BitOrder Data transfer bit order
|
||||||
|
*/
|
||||||
|
template <spi::cpol CPOL,
|
||||||
|
spi::cpha CPHA,
|
||||||
|
spi::bitOrder BitOrder>
|
||||||
|
class spi_bb_i <virtual_tag, CPOL, CPHA, BitOrder> : public spi_i<virtual_tag> {
|
||||||
|
public:
|
||||||
|
using type = spi_bb_i<virtual_tag, CPOL, CPHA, BitOrder>; //!< Export type as identity meta-function
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \name Object lifetime
|
||||||
|
*/
|
||||||
|
//!@{
|
||||||
|
protected:
|
||||||
|
~spi_bb_i () = default; //!< A default destructor, allow destructor from derived only
|
||||||
|
//! \brief A default constructor
|
||||||
|
spi_bb_i (uint32_t clk =1000000) noexcept
|
||||||
|
: nsec_ {1000000000/(2*clk)} {
|
||||||
|
}
|
||||||
|
//!@}
|
||||||
|
|
||||||
|
private:
|
||||||
|
//! \name SPI implementation specific functions
|
||||||
|
//!@{
|
||||||
|
template <spi::cpol C =CPOL> constexpr bool clkHigh () { return !static_cast<bool>(C); }
|
||||||
|
template <spi::cpol C =CPOL> constexpr bool clkLow () { return static_cast<bool>(C); }
|
||||||
|
template <spi::bitOrder B =BitOrder> constexpr
|
||||||
|
use_if_t <(B == spi::bitOrder::LSB_First), void> shift (byte_t& b) { b <<=1; }
|
||||||
|
template <spi::bitOrder B =BitOrder> constexpr
|
||||||
|
use_if_t <(B == spi::bitOrder::MSB_First), void> shift (byte_t& b) { b >>=1; }
|
||||||
|
//!}
|
||||||
|
|
||||||
|
|
||||||
|
//! \name Implementation requirements
|
||||||
|
//!@{
|
||||||
|
private:
|
||||||
|
virtual void MOSI (bool) =0; //!< Implementers's MOSI pin function
|
||||||
|
virtual bool MISO () =0; //!< Implementers's MISO pin function
|
||||||
|
virtual void SCLK (bool) =0; //!< Implementers's SCLK pin function
|
||||||
|
virtual void delay (uint32_t) =0; //!< Implementers's half period delay function
|
||||||
|
//!@}
|
||||||
|
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \name Implementation of base requirements
|
||||||
|
*/
|
||||||
|
//!@{
|
||||||
|
private:
|
||||||
|
uint32_t _clock () const final { return 1000000000/(2*nsec_); }
|
||||||
|
void _clock (uint32_t c) final { nsec_ = 1000000000/(2*c); }
|
||||||
|
byte_t _tx_data (byte_t out) final { return _tx_data_impl (out); }
|
||||||
|
|
||||||
|
template <spi::cpha C =CPHA>
|
||||||
|
use_if_t <(C == spi::cpha::LOW), byte_t> _tx_data_impl (byte_t out);
|
||||||
|
template <spi::cpha C =CPHA>
|
||||||
|
use_if_t <(C == spi::cpha::HIGH), byte_t> _tx_data_impl (byte_t out);
|
||||||
|
|
||||||
|
uint32_t nsec_; //!< half period of SPI bus
|
||||||
|
//!@}
|
||||||
|
};
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief
|
||||||
|
* _tx_data implementation CPHA == LOW
|
||||||
|
* Out at preceding clock trailing edge, In at leading clock edge
|
||||||
|
* \param out The byte to send to SPI bus
|
||||||
|
* \return The byte read from the bus
|
||||||
|
*/
|
||||||
|
template <spi::cpol CPOL, spi::cpha CPHA, spi::bitOrder BitOrder>
|
||||||
|
template <spi::cpha C>
|
||||||
|
use_if_t <(C == spi::cpha::LOW), byte_t>
|
||||||
|
spi_bb_i<virtual_tag, CPOL, CPHA, BitOrder>::_tx_data_impl (byte_t out) {
|
||||||
|
byte_t in {};
|
||||||
|
SCLK (clkLow());
|
||||||
|
for (uint8_t bit {static_cast<uint8_t>(BitOrder)} ; bit ; shift (bit)) {
|
||||||
|
MOSI (out & bit); // Out at preceding clock trailing edge
|
||||||
|
delay (nsec_); // Half cycle delay
|
||||||
|
SCLK (clkHigh()); // Leading edge
|
||||||
|
in |= (MISO ()) ? bit : 0; // In at leading clock edge
|
||||||
|
delay (nsec_); // Half cycle delay
|
||||||
|
SCLK (clkLow()); // Trailing edge
|
||||||
|
}
|
||||||
|
return in;
|
||||||
|
}
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief
|
||||||
|
* _tx_data implementation CPHA == HIGH
|
||||||
|
* Out at leading clock edge, In at trailing clock edge
|
||||||
|
* \param out The byte to send to SPI bus
|
||||||
|
* \return The byte read from the bus
|
||||||
|
*/
|
||||||
|
template <spi::cpol CPOL, spi::cpha CPHA, spi::bitOrder BitOrder>
|
||||||
|
template <spi::cpha C>
|
||||||
|
use_if_t <(C == spi::cpha::HIGH), byte_t>
|
||||||
|
spi_bb_i<virtual_tag, CPOL, CPHA, BitOrder>::_tx_data_impl (byte_t out) {
|
||||||
|
byte_t in {};
|
||||||
|
SCLK (clkLow());
|
||||||
|
for (uint8_t bit {static_cast<uint8_t>(BitOrder)} ; bit ; shift (bit)) {
|
||||||
|
delay (nsec_); // Half cycle delay
|
||||||
|
SCLK (clkHigh()); // Leading edge
|
||||||
|
MOSI (out & bit); // Out at leading clock edge
|
||||||
|
delay (nsec_); // Half cycle delay
|
||||||
|
SCLK (clkLow()); // Trailing edge
|
||||||
|
in |= (MISO ()) ? bit : 0; // In at trailing clock edge
|
||||||
|
}
|
||||||
|
return in;
|
||||||
|
}
|
||||||
|
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif //#ifndef __spi_bb_h__
|
||||||
Loading…
x
Reference in New Issue
Block a user