IEEE 802.15.4/2.4G Switchable Demo

This example demos how to switch between Realtek 2.4G proprietary protocol/IEEE 802.15.4 protocol and transmit data using one protocol at a time.

Note

Due to hardware limitations, it is not possible to simultaneously transmit Realtek 2.4G proprietary protocol packets and IEEE 802.15.4 packets on RTL8752H series chips.

Requirements

The sample supports the following development kits. For more requirements for booting, please refer to Quick Start.

Development Kits
Hardware Platforms	Board Name
RTL8752H HDK	RTL8752H EVB

This demo project requires three EVBs to demo the T/RX of Realtek 2.4G proprietary protocol and IEEE 802.15.4 protocol.

EVB Board Numbers
EVB Board Number	Purpose
EVB Board1	TX packets of Realtek 2.4G proprietary and IEEE 802.15.4
EVB Board2	Realtek 2.4G proprietary Receiver
EVB Board3	Realtek IEEE 802.15.4 Receiver

For the requirements of EVB Board2, please refer to 2.4G Simple TRX.
For the requirements of EVB Board3, please refer to IEEE 802.15.4 TRX.

Wiring

Please refer to RTL8752H EVB Interfaces and Modules in Quick Start.

Configurations

For Realtek 2.4G proprietary configurations, refer to src\app\ppt_154_switch_demo\ppt\ppt_cfg.h.

Note

EVB Board1 and EVB Board2 should share the same proprietary configuration.
For IEEE 802.15.4 configurations, please refer to zb_demo in src\app\ppt_154_switch_demo\zb\zb_main.c. The default configuration has PanID=0x05, ShortAddr=1, Channel=12.
Note
- EVB Board1 and EVB Board3 should share the same IEEE 802.15.4 configuration.
- Please refer to IEEE 802.15.4 TRX for configuring EVB Board3 to receive packets from EVB Board1.

Building and Downloading

This sample can be found in the SDK folder:

Keil

Project file: sdk\board\evb\ppt_154_switch_demo\mdk

GCC

Currently this project only supports Keil compiler.

To build and run the sample, follow the steps listed below:

Open project file.
To build the target, follow the steps listed on the Generating App Image in Quick Start.
After a successful compilation, the APP bin app_MP_sdk_xxx.bin will be generated in the directory bin.
To download APP bin into evaluation board, follow the steps listed on the MP Tool Download in Quick Start.
Press reset button on evaluation board and it will start running.

Experimental Verification

After programming the sample to EVB Board1, use the Debug Analyzer to obtain logs and view the running results.

Testing

After pressing the reset button, EVB Board1 uses a software timer with three-second period to loop the following procedures periodically.

APP receive 3s timeout event from the software timer.
Switch to IEEE 802.15.4 protocol.
Send IEEE 802.15.4 packets.
Idle for next timeout event.
APP receive 3s timeout event from the software timer.
Switch to 2.4G proprietary protocol.
Send 2.4G proprietary packet.
Idle for next timeout event.

2.4G Proprietary

After pressing the reset button and it’s 2.4G’s turn, EVB Board1 will start send 2.4G packets and listen for responses.
If ACK_MODE is enabled, EVB Board2 will send packet back to EVB Board1.
If it is successfully started, the following log will be printed: [APP] !**ptx: statistics tx 95, rx 70, miss 25(26.315%)
After pressing the reset button, EVB Board2 will start listening to the air according to 2.4G proprietary configurations.
If it starts successfully, the following log will be printed when it receives a packet from the air: [APP] !**prx: rx count 1774, int count 2969, rx stack 0x0008, entry 0, hp 0x00, len 15, hs 0x00000000, payload 01 02 01 02 01 01 02 01 05 05 09 32 2E 34 67

Note

Because the default configuration is BLE Advertising Channel 37, which is 2402MHz, PTX may hear the BLE device reply and PRX may hear the BLE device broadcast. You can modify parameters such as FREQUENCY to avoid BLE devices.

IEEE 802.15.4

After pressing the reset button and it’s IEEE 802.15.4’s turn, EVB Board1 will start send IEEE 802.15.4 packets and listen for responses.
If it is successfully started, the following log will be printed: [APP] !**IO_MSG_TYPE_154
Please refer to IEEE 802.15.4 TRX for the testing results of EVB Board3.

Code Overview

The main purpose of this chapter is to help APP developers get familiar with the development process. This chapter will be introduced according to the following several parts:

Source Code Directory.
Chapter Initialization introduce the initialization flow of the chip.
Chapter Switch Flow introduce switching flow and initialization/de-initialization of 2.4G proprietary and IEEE 802.15.4.

Source Code Directory

Project directory: sdk\board\evb\ppt_154_switch_demo\
Source code directory: sdk\src\app\ppt_154_switch_demo\

Source files in the application project are currently categorized into several groups as below.

└── Project: ppt_154_switch_demo
    └── app
        ├── include                  includes rom UUID and part of ISR declaration
        ├── Lib                      includes all binary symbol files that user application is built on
            ├── ROM.lib
            ├── lowerstack.lib
            └── rtl8752h_sdk.lib
        ├── cmsis                    includes vector table declaration and boot code
            ├── startup_rtl876x.s
            └── system_rtl876x.c
        ├── platform                 includes all peripheral drivers and module code used by the application
        ├── ppt driver               includes radio driver
            ├── ppt_driver.c         includes hw registers operation
            └── ppt_simple.c         includes hw management and sw wrapper
        ├──zb_driver                 includes source files for IEEE 802.15.4 protocols
            ├── dbg_printf.c
            ├── patch.c
            ├── strtol.c
            ├── strtoll.c
            ├── strtoul.c
            ├── strtoull.c
            ├── mac_test_common.c
            ├── mac_test_cmds.c
            ├── mac_802154_frame_parser.c
            ├── mac_priv_cmds.c
            ├── mac_driver_ext.c
            ├── cmd_shell.c
            ├── cmd_shell_rom.c
            ├── consol_cmds.c
            ├── shell.c
            └── stdio_port.c
        └── app                      includes the user application implementation
            ├── overlay_mgr.c
            ├── main.c               includes the io, os and platform initialization
            └── app_task.c           includes app task initialization and main loop for protocol switching demo
        └── zb_demo                  includes IEEE 802.15.4 initialization
            └── zb_main.c            includes IEEE 802.15.4 task
        └── ppt_demo
            ├── ppt_cfg.c            includes the radio configurations and initialization
            └── ppt_ptx.c            includes tx and rx operations and interrupt routine

Initialization

When the EVB board boots up and the chip is reset, the main function will be called, which executes the following initialization functions:

int main(void)
 {
     extern uint32_t random_seed_value;
     srand(random_seed_value);
     board_init();
     pwr_mgr_init();
     task_init();
     os_sched_start();
     return 0;
 }

pwr_mgr_init() inits the DLPS power management module.
task_init() inits the app task and register the task main function app_main_task().
os_sched_start() starts the os scheduler. When the scheduler is started, app_main_task() will be called and start the 3-second sw timer for triggering tx event.

void app_main_task(void *p_param)
 {
     os_msg_queue_create(&app_task_evt_queue_handle, APP_TASK_EVT_QUEUE_SIZE,
                         sizeof(uint8_t)); // T_EVENT_TYPE
     os_msg_queue_create(&app_task_io_queue_handle, APP_TASK_IO_QUEUE_SIZE, sizeof(T_IO_MSG));
     /* initialize IEEE 802.15.4 uart log and IEEE 802.15.4 rx task */
     zb_task_init();
     /* avoid confliction with ble psd procedure */
     os_delay(1000);
     os_timer_create(&tx_timer, "tx timer", 1, TX_TIMER_PERIOD, true, tx_timer_callback);
     os_timer_start(&tx_timer);
     T_EVENT_TYPE event;
     while (1)
     {
         if (os_msg_recv(app_task_evt_queue_handle, &event, 0xFFFFFFFF) == true)
         {
             if (event == EVENT_IO_TO_APP)
             {
                 T_IO_MSG msg = {0};
                 if (os_msg_recv(app_task_io_queue_handle, &msg, 0) == true)
                 {
                     app_handle_io_msg(msg);
                 }
             }
         }
     }
 }

Switch Flow

tx_timer_callback() will be referenced every 3 seconds, which sends out a timeout event message with event type IO_MSG_TYPE_TIMER to app_main_task(), where app_handle_io_msg() is responsible for handling all the message events transmitted to app task.
Upon receiving the timeout event, it will trigger corresponding protocol initialization of 2.4G/IEEE 802.15.4, and transmit packet according to pre-defined protocol demo configuration.
After the protocol tx demo is finished, a message with event type IO_MSG_TYPE_MULTIPROTOCOL is issued to app_main_task() The subtype of this message indicates which protocol is applied in this round’s transmission demo.

2.4G Proprietary

Initialize and Configure

ppt_cfg() will initialize and configure the radio, including frequency, PHY type, frame format, CRC parameters, whitening parameters, access address and transmit power.
ppt_reg_handler() register the radio’s interrupt handler.
PTX mode configuration, header settings ppt_set_tx_header(), and prepare the data to be sent ppt_push_tx_data().

Main Loop

PTX will send data in a loop for three times, the process is as follows:

prepare data
enable PTX and wait for completion
modify data content and length
delay 500ms
return to step 1

Radio Interrupt Handler

After enabling PTX or PRX, the radio will run and trigger the corresponding interrupt. The registered interrupt function by ppt_reg_handler() will be called. The interrupt type can be found in 2.4G Radio User Guide.

PTX will process tx_int.
If ACK mode is turned on, rx_int will also be processed.
If periodic mode is turned on, tx_early_int will be processed.
When the number of retransmissions in periodic mode reaches the requirement, PTX will be turned off in the TRX interrupt, and then kill_ptx_int needs to be processed.

After the interrupt handling is complete and 2.4G proprietary hw state machine is in idle state, ppt_send_complete_msg_to_apptask() is referenced to send 2.4G TX complete message with subtype IO_MSG_MPM_PPT to app task.

Deinitialization

When app_handle_io_msg() receives IO_MSG_MPM_PPT event, it executes the following functions to disable 2.4G protocol.

ppt_disable_ptx() blocks cpu until 2.4G proprietary hw state machine is in idle state.
ppt_dlps_deinit() executes dlps related configurations and recover to default state.
ppt_deinit() disables 2.4G MAC and free buffer memory allocated previously.

ppt_disable_ptx(NULL);
ppt_deinit();
ppt_dlps_deinit();

IEEE 802.15.4

Initialize and Configure

zb_mac_enable() is referenced to enable IEEE 802.15.4 protocol.
mac_SetPANId(), mac_SetChannel(), mac_SetShortAddress() are referenced to configure pre-defined IEEE 802.15.4 tx packet.
stub_zb_mac_data() is referenced to transmit IEEE 802.15.4 packets, CPU is blocked until the transmission is completed.

After IEEE 802.15.4 TX finished, IO message with subtype IO_MSG_MPM_154 is sent to app task to notify application.

void zb_demo(void)
{
    zb_mac_disable();
    zb_mac_enable();
    mac_SetPANId(0x5);
    mac_SetChannel(12);
    mac_SetShortAddress(0x1);
    char *cmds[] = {"1", "7", "7"};
    bool ret = stub_zb_mac_data(3, cmds);
    if (ret)
    {
        T_IO_MSG bee_msg = {0};
        bee_msg.type = IO_MSG_TYPE_MULTIPROTOCOL;
        bee_msg.subtype = IO_MSG_MPM_154;
        if (app_send_msg_to_apptask(&bee_msg) == false)
        {
            APP_PRINT_ERROR0("send message to app queue failed");
        }
    }
}

Deinitialization

zb_mac_disable() is referenced to disable IEEE 802.15.4 mac driver.