in \connect SDK\v1.5.0\nrf\samples\bluetooth\peripheral_uart,data number is limited 20 bytes, more than 20bytes BLE will part data in two or more packs to send or receive

[zhouhaifang]

in \connect SDK\v1.5.0\nrf\samples\bluetooth\peripheral_uart,data number is limited 20 bytes, more than 20bytes BLE will part data in two or more packs to send or receive .how can i chang to data number to more bytes. for example , i want to send 200 bytes through COM  in one time and BLE receive 200bytes i one time , relatively HOW to send 200bytes data in one time  through BLE ,not separate 200bytes data in many pack to send

[zhouhaifang]

Einar Thorsrud

thank you

   I konw you ar very busy ,could you take some time to test peripheral_uart in NCS v1.5.0 with a nrf5340_dk kit ,increase the number of ble that could send to a connected APP in a phone . in this nordic community ,few people know the answer。could you spend some time to reprogram the peripheral_uart example . could you accept my mailbox and mail with me?

[zhouhaifang]

zhouhaifang said:

on

no

[Einar Thorsrud]

Hi,

You have some issues in your code, and I suspect you did not configure the stack on the network core. The following quick and dirty changes to the peripheral_uart sample does what you want and I tested to verify that the data length is updated to 80 upon establishing the connection:

Fullscreen 6710.main.c.diff Download

diff --git a/samples/bluetooth/peripheral_uart/src/main.c b/samples/bluetooth/peripheral_uart/src/main.c
index f8d886d6b..b6f04aedc 100644
--- a/samples/bluetooth/peripheral_uart/src/main.c
+++ b/samples/bluetooth/peripheral_uart/src/main.c
@@ -237,6 +237,7 @@ static int uart_init(void)
 static void connected(struct bt_conn *conn, uint8_t err)
 {
 	char addr[BT_ADDR_LE_STR_LEN];
+	printk("Connected\n");
 
 	if (err) {
 		LOG_ERR("Connection failed (err %u)", err);
@@ -249,6 +250,19 @@ static void connected(struct bt_conn *conn, uint8_t err)
 	current_conn = bt_conn_ref(conn);
 
 	dk_set_led_on(CON_STATUS_LED);
+
+
+	printk("Start DLE...\n");
+	struct bt_conn_le_data_len_param data_len_param;
+
+	data_len_param.tx_max_len = 80; // byte
+	data_len_param.tx_max_time = 3750; // us
+
+	err = bt_conn_le_data_len_update(current_conn, &data_len_param);
+	if (err)
+	{
+		printk("LE data length update failed: %d\n", err);
+	}
 }
 
 static void disconnected(struct bt_conn *conn, uint8_t reason)

Fullscreen peripheral_uart_prj.conf.diff Download

diff --git a/samples/bluetooth/peripheral_uart/prj.conf b/samples/bluetooth/peripheral_uart/prj.conf
index cd6df0664..8571bed92 100644
--- a/samples/bluetooth/peripheral_uart/prj.conf
+++ b/samples/bluetooth/peripheral_uart/prj.conf
@@ -48,3 +48,16 @@ CONFIG_LOG_BACKEND_RTT=y
 CONFIG_LOG_BACKEND_UART=n
 
 CONFIG_ASSERT=y
+
+# Added
+CONFIG_BT_USER_DATA_LEN_UPDATE=y
+CONFIG_BT_RX_BUF_LEN=255
+CONFIG_BT_GATT_CLIENT=y
+CONFIG_BT_ATT_TX_MAX=10
+CONFIG_BT_ATT_PREPARE_COUNT=2
+CONFIG_BT_CONN_TX_MAX=10
+CONFIG_BT_L2CAP_TX_BUF_COUNT=10
+CONFIG_BT_L2CAP_TX_MTU=247
+CONFIG_BT_L2CAP_RX_MTU=247
+CONFIG_BT_CTLR_TX_BUFFER_SIZE=251
+CONFIG_BT_CTLR_DATA_LENGTH_MAX=251

Here is update for the network core by changing zephyr\samples\bluetooth\hci_rpmsg\prj.conf (note that I also reduced CONFIG_BT_MAX_CONN in order to make this fit in RAM):

Fullscreen hci_rpmsg_prj.conf.diff Download

diff --git a/samples/bluetooth/hci_rpmsg/prj.conf b/samples/bluetooth/hci_rpmsg/prj.conf
index 46a1992edc..032fdbf54a 100644
--- a/samples/bluetooth/hci_rpmsg/prj.conf
+++ b/samples/bluetooth/hci_rpmsg/prj.conf
@@ -9,10 +9,21 @@ CONFIG_MAIN_STACK_SIZE=512
 CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=512
 CONFIG_BT=y
 CONFIG_BT_HCI_RAW=y
-CONFIG_BT_MAX_CONN=16
+CONFIG_BT_MAX_CONN=4
 CONFIG_BT_CTLR_ASSERT_HANDLER=y
 CONFIG_BT_HCI_RAW_RESERVE=1
 
 CONFIG_ASSERT=y
 CONFIG_DEBUG_INFO=y
 CONFIG_EXCEPTION_STACK_TRACE=y
+
+# Added
+#CONFIG_BT_USER_DATA_LEN_UPDATE=y
+CONFIG_BT_RX_BUF_LEN=255
+CONFIG_BT_L2CAP_TX_MTU=247
+CONFIG_BT_L2CAP_RX_MTU=247
+CONFIG_BT_CTLR_TX_BUFFER_SIZE=251
+CONFIG_BT_CTLR_DATA_LENGTH_MAX=251
+
+
+

[zhouhaifang]

thank Einar Thorsrud!

I changed example as you had told to me . i build solution.use git_cmd,erase cpu net,in main.c change #define UART_BUF_SIZE 20 into #define UART_BUF_SIZE 70 ,in uart_cb() 

case UART_RX_RDY:

......
if (buf->len == 40) {
......
}

build/debug ,go ,from ble of board ,the largest bytes is still 20  that can be send to APP. 

do zephyr\samples\bluetooth\hci_rpmsg\prj.conf have no  effect to cpu_net core of example peripheral_uart ? 

i program the cpu_net core of example peripheral_uart  with \nrf\samples\bluetooth\peripheral_uart\build_nrf5340dk_nrf5340_cpuappns\hci_rpmsg\zephyr\ merged_CPUNET.hex .

program can run well  and connect with app and not reset.

[zhouhaifang]

when debug go there are informatipn below:

[00:00:00.028,442]  bt_hci_core: ECC HCI commands not available

[00:00:00.028,472]  bt_hci_core: No ID address. App must call settings_load()

[00:00:00.028,472]  peripheral_uart: Bluetooth initialized

[zhouhaifang]

[zhouhaifang]

 when I send data from sscom's send editor  more than 20 bytes ,the debugging segger embedded studio pop information below:

[00:01:23.371,826]  bt_att: No ATT channel for MTU 43
[00:01:23.371,856] bt_gatt: No buffer available to send notification
[00:01:23.371,856] peripheral_uart: Failed to send data over BLE connection
[00:01:37.619,506]  bt_att: No ATT channel for MTU 48
[00:01:37.619,537] bt_gatt: No buffer available to send notification
[00:01:37.619,537]  peripheral_uart: Failed to send data over BLE connection
[00:01:37.910,400] bt_att: No ATT channel for MTU 48
[00:01:37.910,400]  bt_gatt: No buffer available to send notification
[00:01:37.910,430]  peripheral_uart: Failed to send data over BLE connection
[00:01:38.141,235]  bt_att: No ATT channel for MTU 48
[00:01:38.141,235]  bt_gatt: No buffer available to send notification
[00:01:38.141,265]  peripheral_uart: Failed to send data over BLE connection
[00:01:38.332,031]  bt_att: No ATT channel for MTU 48
[00:01:38.332,061] bt_gatt: No buffer available to send notification
[00:01:38.332,061] peripheral_uart: Failed to send data over BLE connection
[00:01:38.532,836]  bt_att: No ATT channel for MTU 48
[00:01:38.532,867]  bt_gatt: No buffer available to send notification
[00:01:38.532,867] peripheral_uart: Failed to send data over BLE connection
[00:01:38.723,632] bt_att: No ATT channel for MTU 48
[00:01:38.723,632]  bt_gatt: No buffer available to send notification
[00:01:38.723,663] peripheral_uart: Failed to send data over BLE connection
[00:01:38.994,506]  bt_att: No ATT channel for MTU 48
[00:01:38.994,506]  bt_gatt: No buffer available to send notification
[00:01:38.994,537]  peripheral_uart: Failed to send data over BLE connection
[00:01:39.195,312]  bt_att: No ATT channel for MTU 48
[00:01:39.195,343] bt_gatt: No buffer available to send notification
[00:01:39.195,343]  peripheral_uart: Failed to send data over BLE connection
[00:01:39.376,098]  bt_att: No ATT channel for MTU 48
[00:01:39.376,129] bperipheral_uart: Failed to send data over BLE connection