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#pragma once
#include "pb-types.h"
/**
* This is the RP2040 puzzle bus driver. This file is no longer inside
* lib/pb//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.
*
* The workaround implemented in this driver was already kind of messy, and a
* different microcontroller should be used for the main controller instead.
*/
#ifdef __cplusplus
extern "C" {
#endif
//! puzzle bus driver setup
void pb_setup();
/**
* 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.
*
* 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.
*
* As a result of the RP2040 hardware limitations detailed at the top of this
* file, this function is also implemented in this file, even through it does
* not belong to the puzzle bus driver. In order to not miss any handshake
* responses, the bus should remain busy during the entire scan.
*/
void bus_scan();
#ifdef __cplusplus
}
#endif
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