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rt-thread-official/bsp/raspberry-pi/raspi4-32/driver/drv_bluetooth.c

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/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2020-11-29 bigmagic first version
*/
#include <rthw.h>
#include <rtthread.h>
#include "drv_bluetooth.h"
#include "drv_uart.h"
#include "raspi4.h"
//https://github.com/RPi-Distro/bluez-firmware/tree/master/broadcom
//arm-none-eabi-objcopy.exe -I binary -O elf32-littlearm -B arm driver\BCM4345C0.hcd driver\BCM4345C0.a
#define BT_UART_NAME "uart0"
#define BT_TX_MAX (256)
#define BT_RX_MAX (256)
#define BT_HEAD_NUM (4)
#define BT_TRY_NUM_MAX (3)
#define BT_SEND_MIN_PACK (8)
unsigned char lo(unsigned int val) { return (unsigned char)(val & 0xff); }
unsigned char hi(unsigned int val) { return (unsigned char)((val & 0xff00) >> 8); }
#define BT_THREAD_STACK_SIZE (2048)
#define BT_THREAD_PRIORITY (15)
#define BT_THREAD_TICK (10)
enum
{
LE_EVENT_CODE = 0x3e,
LE_CONNECT_CODE = 0x01,
LE_ADREPORT_CODE = 0x02,
HCI_ACL_PKT = 0x02,
HCI_EVENT_PKT = 0x04
};
static char ch;
static rt_sem_t bt_rx_sem = RT_NULL;
static rt_device_t bt_device;
static rt_uint8_t tx_buff[BT_TX_MAX];
static rt_uint8_t rx_buff[BT_RX_MAX];
static rt_err_t bt_rx_ind(rt_device_t dev, rt_size_t size)
{
rt_sem_release(bt_rx_sem);
return RT_EOK;
}
int bt_uart_send_data(rt_device_t dev, rt_uint32_t *buf, int len)
{
return rt_device_write(dev, 0, buf, len);
}
void bt_uart_receive_flush(rt_device_t dev)
{
rt_device_read(dev, RT_NULL, rx_buff, BT_RX_MAX);
}
int bt_uart_receive_data(rt_device_t dev, rt_uint8_t *buf, rt_uint32_t *len, rt_int32_t time)
{
rt_uint16_t ii = 0;
ii = rt_device_read(dev, 0, buf, BT_RX_MAX);
*len = ii;
return ii;
}
void bt_data_pack(rt_uint8_t *tx_buff, rt_uint8_t ogf, rt_uint8_t ocf, rt_uint32_t data_len)
{
tx_buff[0] = BT_HCI_COMMAND_PKT;
tx_buff[1] = ogf; //hi(ogf << 10 | ocf);//opcode hi
tx_buff[2] = ocf; //lo(ogf << 10 | ocf);//opcode lo
tx_buff[3] = data_len;
}
rt_uint32_t bt_reply_check(const rt_uint8_t *buff, rt_uint16_t ogf, rt_uint16_t ocf, int pack_len)
{
//step 1
if (buff[0] != BT_HCI_EVENT_PKT)
{
return 1;
}
//step2
if (buff[1] == BT_CONNECT_COMPLETE_CODE)
{
if (buff[2] != 4)
{
return 2;
}
//err code
if (buff[3] != 0)
{
rt_kprintf("Saw HCI COMMAND STATUS error:%d", buff[3]);
return 12;
}
if (buff[4] == 0)
{
return 3;
}
if (buff[5] != ogf)
{
return 4;
}
if (buff[6] != ocf)
{
return 5;
}
}
else if (buff[1] == BT_COMMAND_COMPLETE_CODE)
{
if (buff[2] != 4)
{
return 6;
}
if (buff[3] == 0)
{
return 7;
}
if (buff[4] != ogf)
{
return 8;
}
if (buff[5] != ocf)
{
return 9;
}
if (buff[6] == 0)
{
return 10;
}
}
else
{
return 11;
}
return 0;
}
rt_err_t bt_loadfirmware(void)
{
int ii = 0;
int ret = 0;
int recv_len = BT_RX_MAX;
int step = 0;
rt_uint8_t ogf, ocf;
rt_memset(tx_buff, 0, BT_TX_MAX);
ogf = hi(BT_OGF_VENDOR << 10 | BT_COMMAND_LOAD_FIRMWARE);
ocf = lo(BT_OGF_VENDOR << 10 | BT_COMMAND_LOAD_FIRMWARE);
bt_data_pack(tx_buff, ogf, ocf, 0);
int kk = 0;
for (ii = 0; ii < BT_TRY_NUM_MAX; ii++)
{
recv_len = BT_RX_MAX;
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, BT_SEND_MIN_PACK);
rt_thread_mdelay(5);
ret = bt_uart_receive_data(bt_device, rx_buff, &recv_len, 2000);
if (ret > 0)
{
ret = bt_reply_check(rx_buff, ogf, ocf, RT_NULL);
if (ret == 0)
{
step = 1;
break;
}
else
{
rt_kprintf("err code is %d\n", ret);
}
}
}
if (step == 1)
{
extern unsigned char _binary_driver_BCM4345C0_hcd_size[];
extern unsigned char _binary_driver_BCM4345C0_hcd_start[];
unsigned int c = 0;
unsigned int size = (long)&_binary_driver_BCM4345C0_hcd_size;
while (c < size)
{
//unsigned char opcodebytes[] = {_binary_BCM4345C0_hcd_start[c], _binary_BCM4345C0_hcd_start[c + 1]};
unsigned char length = _binary_driver_BCM4345C0_hcd_start[c + 2];
unsigned char *data = &(_binary_driver_BCM4345C0_hcd_start[c + 3]);
rt_memset(tx_buff, 0, BT_TX_MAX);
ogf = _binary_driver_BCM4345C0_hcd_start[c + 1];
ocf = _binary_driver_BCM4345C0_hcd_start[c];
bt_data_pack(tx_buff, ogf, ocf, length);
rt_memcpy(&tx_buff[BT_HEAD_NUM], data, length);
int kk = 0;
for (ii = 0; ii < BT_TRY_NUM_MAX; ii++)
{
recv_len = BT_RX_MAX;
rt_memset(rx_buff, 0, BT_TX_MAX);
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, length + BT_HEAD_NUM);
bt_uart_receive_flush(bt_device);
rt_thread_mdelay(5);
ret = bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
if (ret > 0)
{
ret = bt_reply_check(rx_buff, ogf, ocf, RT_NULL);
if (ret == 0)
{
step = 2;
break;
}
else
{
rt_kprintf("err code is %d\n", ret);
}
}
}
if (ii >= 3)
{
step = 3;
break;
}
c += 3 + length;
}
if (step != 3)
{
return RT_EOK;
}
}
else
{
return -RT_ERROR;
}
return -RT_ERROR;
}
rt_err_t bt_setbaud(void)
{
static unsigned char params[] = {0, 0, 0x00, 0xc2, 0x01, 0x00}; // little endian, 115200
int params_len = 6;
int ii = 0;
int ret = 0;
int recv_len = BT_RX_MAX;
rt_uint16_t ogf, ocf;
rt_memset(tx_buff, 0, BT_TX_MAX);
ogf = hi(BT_OGF_VENDOR << 10 | BT_COMMAND_SET_BAUD);
ocf = lo(BT_OGF_VENDOR << 10 | BT_COMMAND_SET_BAUD);
bt_data_pack(tx_buff, ogf, ocf, params_len);
//rt_memcpy(&tx_buff[BT_HEAD_NUM], params, params_len);
tx_buff[4] = 0x00;
tx_buff[5] = 0x01;
tx_buff[6] = 0xc2;
tx_buff[7] = 0x00;
tx_buff[8] = 0x00;
tx_buff[9] = 0x00;
for (ii = 0; ii < BT_TRY_NUM_MAX; ii++)
{
recv_len = BT_RX_MAX;
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, params_len + BT_HEAD_NUM);
rt_thread_mdelay(5);
ret = bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
if (ret > 0)
{
ret = bt_reply_check(rx_buff, ogf, ocf, RT_NULL);
if (ret == 0)
{
return RT_EOK;
}
else
{
rt_kprintf("err code is %d\n", ret);
}
}
}
return -RT_ERROR;
}
rt_err_t setLEeventmask(unsigned char mask)
{
unsigned char params[] = {mask, 0, 0, 0, 0, 0, 0, 0};
//static unsigned char params[] = { 0xee, 0xff, 0xc0, 0xee, 0xff, 0xc0 }; // reversed
int params_len = 8;
int ii = 0;
int ret = 0;
int recv_len = BT_RX_MAX;
rt_uint16_t ogf, ocf;
rt_memset(tx_buff, 0, BT_TX_MAX);
ogf = hi(BT_OGF_LE_CONTROL << 10 | 0x01);
ocf = lo(BT_OGF_LE_CONTROL << 10 | 0x01);
bt_data_pack(tx_buff, ogf, ocf, params_len);
//rt_memcpy(&tx_buff[BT_HEAD_NUM], params, params_len);
tx_buff[4] = params[0];
tx_buff[5] = params[1];
tx_buff[6] = params[2];
tx_buff[7] = params[3];
tx_buff[8] = params[4];
tx_buff[9] = params[5];
tx_buff[10] = params[6];
tx_buff[11] = params[7];
for (ii = 0; ii < BT_TRY_NUM_MAX; ii++)
{
recv_len = BT_RX_MAX;
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, params_len + BT_HEAD_NUM);
rt_thread_mdelay(5);
ret = bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
if (ret > 0)
{
ret = bt_reply_check(rx_buff, ogf, ocf, RT_NULL);
if (ret == 0)
{
return RT_EOK;
}
else
{
rt_kprintf("err code is %d\n", ret);
}
}
}
return -RT_ERROR;
//if (hciCommand(OGF_LE_CONTROL, 0x01, params, 8)) uart_writeText("setLEeventmask failed\n");
}
rt_err_t bt_getbdaddr(unsigned char *bdaddr)
{
static unsigned char params[] = {0x00, 0x10, 0x09, BT_HCI_COMMAND_PKT}; //get bdaddr
int params_len = 4;
int recv_len = BT_RX_MAX;
// rt_memcpy(tx_buff, params, 4);
tx_buff[0] = BT_HCI_COMMAND_PKT;
tx_buff[1] = 0x09;
tx_buff[2] = 0x10;
tx_buff[3] = 0x00;
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, 4);
rt_thread_mdelay(100);
bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
if (recv_len > 0)
{
if ((rx_buff[0] != BT_HCI_EVENT_PKT) || (rx_buff[1] != BT_COMMAND_COMPLETE_CODE))
{
return -RT_ERROR;
}
if ((rx_buff[2] != 0x0a) || (rx_buff[3] != 0x01))
{
return -RT_ERROR;
}
if ((rx_buff[4] != 0x09) || (rx_buff[5] != 0x10))
{
return -RT_ERROR;
}
bdaddr[0] = rx_buff[7];
bdaddr[1] = rx_buff[8];
bdaddr[2] = rx_buff[9];
bdaddr[3] = rx_buff[10];
bdaddr[4] = rx_buff[11];
bdaddr[5] = rx_buff[12];
}
else
{
return -RT_ERROR;
}
return RT_EOK;
}
rt_err_t setLEscanenable(unsigned char state, unsigned char duplicates)
{
unsigned char params[] = {state, duplicates};
//static unsigned char params[] = { 0xee, 0xff, 0xc0, 0xee, 0xff, 0xc0 }; // reversed
int params_len = 2;
int ii = 0;
int ret = 0;
int recv_len = BT_RX_MAX;
rt_uint16_t ogf, ocf;
rt_memset(tx_buff, 0, BT_TX_MAX);
ogf = hi(BT_OGF_LE_CONTROL << 10 | 0x0c);
ocf = lo(BT_OGF_LE_CONTROL << 10 | 0x0c);
bt_data_pack(tx_buff, ogf, ocf, params_len);
tx_buff[4] = params[0];
tx_buff[5] = params[1];
//rt_memcpy(&tx_buff[BT_HEAD_NUM], params, params_len);
for (ii = 0; ii < BT_TRY_NUM_MAX; ii++)
{
recv_len = BT_RX_MAX;
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, params_len + BT_HEAD_NUM);
rt_thread_mdelay(5);
ret = bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
if (ret > 0)
{
ret = bt_reply_check(rx_buff, ogf, ocf, RT_NULL);
if (ret == 0)
{
return RT_EOK;
}
else
{
rt_kprintf("err code is %d\n", ret);
}
}
}
return -RT_ERROR;
}
rt_err_t setLEscanparameters(unsigned char type, unsigned char linterval, unsigned char hinterval, unsigned char lwindow, unsigned char hwindow, unsigned char own_address_type, unsigned char filter_policy)
{
unsigned char params[] = {type, linterval, hinterval, lwindow, hwindow, own_address_type, filter_policy};
int params_len = 7;
int ii = 0;
int ret = 0;
int recv_len = BT_RX_MAX;
rt_uint16_t ogf, ocf;
rt_memset(tx_buff, 0, BT_TX_MAX);
ogf = hi(BT_OGF_LE_CONTROL << 10 | 0x0b);
ocf = lo(BT_OGF_LE_CONTROL << 10 | 0x0b);
bt_data_pack(tx_buff, ogf, ocf, params_len);
tx_buff[4] = params[0];
tx_buff[5] = params[1];
tx_buff[6] = params[2];
tx_buff[7] = params[3];
tx_buff[8] = params[4];
tx_buff[9] = params[5];
tx_buff[10] = params[6];
//rt_memcpy(&tx_buff[BT_HEAD_NUM], params, params_len);
for (ii = 0; ii < BT_TRY_NUM_MAX; ii++)
{
recv_len = BT_RX_MAX;
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, params_len + BT_HEAD_NUM);
rt_thread_mdelay(5);
ret = bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
if (ret > 0)
{
ret = bt_reply_check(rx_buff, ogf, ocf, RT_NULL);
if (ret == 0)
{
return RT_EOK;
}
else
{
rt_kprintf("err code is %d\n", ret);
}
}
}
return -RT_ERROR;
}
rt_err_t startActiveScanning()
{
float BleScanInterval = 60; // every 60ms
float BleScanWindow = 60;
float BleScanDivisor = 0.625;
unsigned int p = BleScanInterval / BleScanDivisor;
unsigned int q = BleScanWindow / BleScanDivisor;
if (setLEscanparameters(BT_LL_SCAN_ACTIVE, lo(p), hi(p), lo(q), hi(q), 0, 0) == RT_EOK)
{
rt_kprintf("setLEscanparameters ok!\n");
}
if (setLEscanenable(1, 0) == RT_EOK)
{
rt_kprintf("setLEscanenable ok!\n");
}
}
rt_err_t bt_setbdaddr(void)
{
static unsigned char params[] = {0xee, 0xff, 0xc0, 0xee, 0xff, 0xc0}; // reversed
int params_len = 6;
int ii = 0;
int ret = 0;
int recv_len = BT_RX_MAX;
rt_uint16_t ogf, ocf;
rt_memset(tx_buff, 0, BT_TX_MAX);
ogf = hi(BT_OGF_VENDOR << 10 | BT_COMMAND_SET_BDADDR);
ocf = lo(BT_OGF_VENDOR << 10 | BT_COMMAND_SET_BDADDR);
bt_data_pack(tx_buff, ogf, ocf, params_len);
tx_buff[4] = 0xc0;
tx_buff[5] = 0xff;
tx_buff[6] = 0xee;
tx_buff[7] = 0xc0;
tx_buff[8] = 0xff;
tx_buff[9] = 0xee;
//rt_memcpy(&tx_buff[BT_HEAD_NUM], params, params_len);
for (ii = 0; ii < BT_TRY_NUM_MAX; ii++)
{
recv_len = BT_RX_MAX;
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, params_len + BT_HEAD_NUM);
rt_thread_mdelay(5);
ret = bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
if (ret > 0)
{
ret = bt_reply_check(rx_buff, ogf, ocf, RT_NULL);
if (ret == 0)
{
return RT_EOK;
}
else
{
rt_kprintf("err code is %d\n", ret);
}
}
}
return -RT_ERROR;
}
rt_err_t bt_reset(void)
{
int ii = 0;
int ret = 0;
int recv_len = BT_RX_MAX;
rt_uint16_t ogf, ocf;
rt_memset(tx_buff, 0, BT_TX_MAX);
ogf = hi(BT_OGF_HOST_CONTROL << 10 | BT_COMMAND_RESET_CHIP);
ocf = lo(BT_OGF_HOST_CONTROL << 10 | BT_COMMAND_RESET_CHIP);
bt_data_pack(tx_buff, ogf, ocf, 0);
for (ii = 0; ii < BT_TRY_NUM_MAX; ii++)
{
recv_len = BT_RX_MAX;
bt_uart_receive_flush(bt_device);
bt_uart_send_data(bt_device, tx_buff, 8);
rt_thread_mdelay(5);
ret = bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
//rt_kprintf("recv_len is %d\n", recv_len);
if (ret > 0)
{
ret = bt_reply_check(rx_buff, ogf, ocf, RT_NULL);
if (ret == 0)
{
return RT_EOK;
}
else
{
rt_kprintf("err code is %d\n", ret);
}
}
}
return -RT_ERROR;
}
rt_device_t bt_uart_init(const char *uartname)
{
rt_device_t dev = RT_NULL;
if (strcmp(uartname, BT_UART_NAME) == 0)
{
bt_rx_sem = rt_sem_create("btbuf", 0, RT_IPC_FLAG_FIFO);
dev = rt_device_find(uartname);
if (dev == RT_NULL)
{
rt_kprintf("can no find dev %s\n", uartname);
return dev;
}
if (rt_device_open(dev, RT_DEVICE_OFLAG_RDWR) == RT_EOK)
{
rt_device_set_rx_indicate(dev, bt_rx_ind);
}
return dev;
}
return dev;
}
static void bt_task_entry(void *param)
{
while (1)
{
rt_thread_delay(1000);
}
}
#define MAX_MSG_LEN 50
#define MAX_READ_RUN 100
unsigned char data_buf[MAX_MSG_LEN];
unsigned int data_len;
unsigned int messages_received = 0;
unsigned int poll_state = 0;
unsigned int got_echo_sid = 0;
unsigned int got_echo_name = 0;
unsigned char echo_addr[6];
void hci_poll2(unsigned char byte)
{
switch (poll_state)
{
case 0:
if (byte != HCI_EVENT_PKT)
poll_state = 0;
else
poll_state = 1;
break;
case 1:
if (byte != LE_EVENT_CODE)
poll_state = 0;
else
poll_state = 2;
break;
case 2:
if (byte > MAX_MSG_LEN)
poll_state = 0;
else
{
poll_state = 3;
data_len = byte;
}
break;
default:
data_buf[poll_state - 3] = byte;
if (poll_state == data_len + 3 - 1)
{
messages_received++;
poll_state = 0;
}
else
poll_state++;
}
}
unsigned char *hci_poll()
{
int recv_len = 256;
unsigned int goal = messages_received + 1;
bt_uart_receive_data(bt_device, rx_buff, &recv_len, 1000);
rt_thread_mdelay(10);
if (recv_len > 0)
{
unsigned int run = 0;
while (run < MAX_READ_RUN && messages_received < goal)
{
recv_len = recv_len - 1;
hci_poll2(rx_buff[recv_len]);
run++;
if (recv_len == 0)
{
break;
}
}
if (run == MAX_READ_RUN)
return 0;
else
return data_buf;
}
return 0;
}
void bt_search()
{
unsigned char *buf;
while ((buf = hci_poll()))
{
if (data_len >= 2)
{
if (buf[0] == LE_ADREPORT_CODE)
{
unsigned char numreports = buf[1];
if (numreports == 1)
{
unsigned char event_type = buf[2];
if (event_type == 0x00)
{
unsigned char buf_len = buf[10];
unsigned char ad_len = buf[11];
if (ad_len < data_len && buf_len + 11 == data_len - 1)
{
for (int c = 9; c >= 4; c--)
echo_addr[9 - c] = buf[c];
buf += 11;
got_echo_sid = 0;
got_echo_name = 0; // Reset the search state machine
do
{
ad_len = buf[0];
unsigned char ad_type = buf[1];
buf += 2;
if (ad_len >= 2)
{
if (ad_type == 0x03)
{
unsigned int sid = 0;
for (int d = 0; d < ad_len - 1; d += 2)
{
sid = buf[d] | (buf[d + 1] << 8);
if (sid == 0xEC00)
{
rt_kprintf("sid is %d\n", sid);
//uart_hex(sid); uart_writeText(" ");
got_echo_sid = 1;
}
}
}
else if (ad_type == 0x09)
{
char remote_name[ad_len - 1];
unsigned int d = 0;
while (d < ad_len - 1)
{
remote_name[d] = buf[d];
d++;
}
if (!memcmp(remote_name, "echo", 4))
{
rt_kprintf("remote_name is %s\n", remote_name);
got_echo_name = 1;
}
}
}
buf += ad_len - 1;
} while (buf[1]);
}
}
}
}
}
}
}
void bt_uart_protocol_init()
{
rt_thread_t bt_tid = RT_NULL;
bt_device = bt_uart_init(BT_UART_NAME);
bt_tid = rt_thread_create("bt_task", bt_task_entry, RT_NULL, BT_THREAD_STACK_SIZE, BT_THREAD_PRIORITY, BT_THREAD_TICK);
if (bt_tid == RT_NULL)
{
rt_kprintf("bt_task create err!\n");
return 0;
}
rt_thread_startup(bt_tid);
}
int rt_hw_bluetooth_init(void)
{
bt_uart_protocol_init();
if (bt_reset() == RT_EOK)
{
rt_kprintf("bluetooth reset ok!\n");
}
else
{
rt_kprintf("bluetooth reset err!\n");
}
rt_thread_delay(10);
if (bt_loadfirmware() == RT_EOK)
{
rt_kprintf("loadfirmware ok!\n");
}
else
{
rt_kprintf("loadfirmware err!\n");
}
rt_thread_delay(10);
if (bt_setbaud() == RT_EOK)
{
rt_kprintf("setbaud ok!\n");
}
else
{
rt_kprintf("setbaud err!\n");
}
rt_thread_delay(10);
if (bt_setbdaddr() == RT_EOK)
{
rt_kprintf("setbdaddr ok!\n");
}
else
{
rt_kprintf("setbdaddr err!\n");
}
rt_thread_delay(100);
rt_uint8_t bdaddr[6];
if (bt_getbdaddr(bdaddr) == RT_EOK)
{
rt_kprintf("bdaddr :%02x:%02x:%02x:%02x:%02x:%02x\n", bdaddr[0], bdaddr[1], bdaddr[2], bdaddr[3], bdaddr[4], bdaddr[5]);
}
else
{
rt_kprintf("getbdaddr err!\n");
}
rt_thread_delay(100);
if (setLEeventmask(0xff) == RT_EOK)
{
rt_kprintf("setLEeventmask ok!\n");
}
rt_thread_delay(100);
startActiveScanning();
rt_thread_delay(500);
rt_kprintf("start!\n");
while (1)
{
bt_search();
if (got_echo_sid && got_echo_name)
{
break;
}
rt_thread_mdelay(10);
}
rt_kprintf("stop scan!\n");
}
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