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/*
* Copyright (C) 2015-2017 Freie Universität Berlin
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @defgroup drivers_nrf5x_nrfmin NRF minimal radio driver
* @ingroup drivers_netdev
* @brief Minimal driver for the NRF51 radio
*
* This driver uses the nRF5x radio in a proprietary/custom way, defining our
* own custom link layer. This custom link layer resembles some characteristics
* of the IEEE802.15.4 link layer, but is not at all compatible to it.
*
* One key point is, that this custom link layer is only meant to operate
* between nRF5x devices, which let's us make some very nice assumptions:
* - all communicating hosts are little-endian
* -> we define host byte order := network byte order
*
* The driver is using a Nordic proprietary physical layer, configured to a
* bitrate of 2Mbit. The maximum payload length can be freely configured, but
* the maximal supported value is 250 byte (default is 200 byte).
*
* We define the nrfmin link layer to use 16-bit addresses. On the physical
* layer we encode these addresses by putting these addresses into the 2 least
* significant bytes of the supported 5-byte addresses, while setting the other
* 3 bytes to 0xe7.
*
* For out custom link layer, we define our own proprietary link layer format
* (all fields are in host byte order (little endian)):
*
* byte0 | byte1 - byte2 | byte3 - byte4 | byte5 | byte7 - byteN
* ------ | ------------- | ------------- | ----- | -------------
* length | src_addr | dst_addr | proto | payload...
*
* With:
* - length: length of the packet, including the header -> payload len + 6
* - src_addr: 16-bit source address
* - dst_addr: 16-bit destination address
* - proto: type of data transferred (similar to an Ethertype field)
*
* SUMMARY:
* This driver / link layer supports:
* - 16-bit addressing (16-bit)
* -> extract default address from CPU ID
* - broadcast (broadcast address is ff:ff)
* - channels from 0 to 31 [2400MHz to 2524MHz, 4MHz per channel]
* - setting of TX power [+4dBm to -20dBm, in ~4dBm steps]
* - 8-bit packet type/proto field (to be used as seen fit)
* - setting device state (RX, SLEEP)
*
* But so far no support for:
* - link layer ACKs
* - retransmissions
*
* @todo So far the driver uses only a single RX buffer that is locked
* until the data was read/discarded. This can potentially lead to
* a lot of packet loss -> using more than one buffer would help
* here...
*
* @{
*
* @file
* @brief Interface definition for the nrfmin NRF51822 radio driver
*
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*/
#ifndef NRFMIN_H
#define NRFMIN_H
#include "net/netdev.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief nrfmin channel configuration
* @{
*/
#define NRFMIN_CHAN_MIN (0U)
#define NRFMIN_CHAN_DEFAULT (0U) /* 2400MHz */
#define NRFMIN_CHAN_MAX (32)
/** @} */
/**
* @brief Default transmission power used
*/
#define NRFMIN_TXPOWER_DEFAULT (0) /* 0dBm */
/**
* @brief Export the default nrfmin broadcast address
*/
#define NRFMIN_ADDR_BCAST (0xffff)
/**
* @brief Default maximum payload length (must be <= 250)
*/
#ifndef NRFMIN_PAYLOAD_MAX
#define NRFMIN_PAYLOAD_MAX (200U)
#endif
/**
* @brief Export some information on header and packet lengths
* @{
*/
#define NRFMIN_HDR_LEN (sizeof(nrfmin_hdr_t))
#define NRFMIN_PKT_MAX (NRFMIN_HDR_LEN + NRFMIN_PAYLOAD_MAX)
/** @} */
/**
* @brief Header format used for our custom nrfmin link layer
*/
typedef struct __attribute__((packed)) {
uint8_t len; /**< packet length, including this header */
uint16_t src_addr; /**< source address of the packet */
uint16_t dst_addr; /**< destination address */
uint8_t proto; /**< protocol of payload */
} nrfmin_hdr_t;
/**
* @brief In-memory structure of a nrfmin radio packet
*/
typedef union {
struct __attribute__((packed)) {
nrfmin_hdr_t hdr; /**< the nrfmin header */
uint8_t payload[NRFMIN_PAYLOAD_MAX]; /**< actual payload */
} pkt; /**< typed packet access */
uint8_t raw[NRFMIN_PKT_MAX]; /**< raw packet access */
} nrfmin_pkt_t;
/**
* @brief Export the netdev device descriptor
*/
extern netdev_t nrfmin_dev;
/**
* @brief Reference to the netdev driver interface
*/
extern const netdev_driver_t nrfmin_netdev;
/**
* @brief Setup the device driver's data structures
*/
void nrfmin_setup(void);
/**
* @brief Get the currently active address
* @return the 16-bit node address
*/
uint16_t nrfmin_get_addr(void);
/**
* @brief Set the 16-bit radio address
*
* @param[in] addr address to set
*/
void nrfmin_set_addr(uint16_t addr);
/**
* @brief Get a pseudo 64-bit long address (needed by IPv6 and 6LoWPAN)
*
* As we do not support 64-bit addresses, we just make one up, for this we
* simply return 4 times concatenated the 16-bit address.
*
* @param[out] addr 64-bit pseudo long address, as array of 4 * 16-bit
*/
void nrfmin_get_pseudo_long_addr(uint16_t *addr);
/**
* @brief Get the IID build from the 16-bit node address
*
* @param[out] iid the 64-bit IID, as array of 4 * 16-bit
*/
void nrfmin_get_iid(uint16_t *iid);
/**
* @brief Get the current channel
*
* @return currently active channel
*/
uint16_t nrfmin_get_channel(void);
/**
* @brief Set the active channel
*
* @param[in] chan targeted channel [0-31]
*
* @return sizeof(uint16_t) on success
* @return -EOVERFLOW if channel is not applicable
*/
int nrfmin_set_channel(uint16_t chan);
/**
* @brief Get the current radio state
*
* @return state the radio is currently in
*/
netopt_state_t nrfmin_get_state(void);
/**
* @brief Put the device into the given state
*
* @param[in] val target state
*
* @return sizeof(netopt_state_t) on success
* @return -ENOTSUP if target state is not applicable
*/
int nrfmin_set_state(netopt_state_t val);
/**
* @brief Get the current transmit power
*
* @return transmission power in [dBm]
*/
int16_t nrfmin_get_txpower(void);
/**
* @brief Set the used transmission power
*
* @param[in] power targeted power, in [dBm]
*/
void nrfmin_set_txpower(int16_t power);
#ifdef __cplusplus
}
#endif
#endif /* NRFMIN_H */
/** @} */