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#pragma once
#include "pb-types.h"
/**
* \ingroup pb_drv
* \defgroup pb_drv_rp2040 RP2040
* \brief Raspberry Pi Pico and Pico W driver
*
* \note This file is no longer inside `lib/pbdrv/drv/rp2040` as it is tightly
* coupled to both the pico-sdk and FreeRTOS functions. I have tried to get
* FreeRTOS to play nicely with the CMake subproject layout, but the pico-sdk
* and the RP2040 port of FreeRTOS both rely on CMake's import() functionality,
* which makes using FreeRTOS in a libary context extremely messy.
*
* \warning The workaround implemented in this driver was already kind of
* messy, and **a different microcontroller should be used for the main
* controller instead**. Please see the handover document for more details.
*
* \{
*/
#ifdef __cplusplus
extern "C" {
#endif
//! Puzzle bus driver setup
void pb_setup();
/**
* \note While the RP2040's datasheet claims it supports multi-master
* configurations by implementing bus arbitration, it does not natively support
* a mode where it is configured as a (multi-)master with a slave address, such
* that it can be addressed by other multi-masters. This function includes a
* hacky workaround that teporarily sets the RP2040 to I2C master mode to send
* a message, and then restores it back to slave mode.
*
* \warning This approach results in some received frames being (partially)
* dropped in the time period between the invocation of this function and the
* bus becoming idle (and the message is sent).
*/
void pb_i2c_send(i2c_addr_t addr, const uint8_t * buf, size_t sz);
/**
* \brief Scan the bus for I2C slaves, and send handshake messages to ACK-ing
* slaves.
*
* \note As a result of the RP2040 hardware limitations, this function is also
* implemented in this file, even though it does not belong to the puzzle bus
* driver.
*
* \warning In order to not miss any handshake responses, the bus should remain
* busy during the entire scan. The \c nostop parameter of the \c
* i2c_write_timeout_us() function from the pico-sdk does not seem to keep the
* bus busy.
*/
void bus_scan();
/// \}
#ifdef __cplusplus
}
#endif
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