ULP LP 内核协处理器编程
ULP LP 内核 (Low-power core) 协处理器是 ESP32-C6 中 ULP 的一个变型。它具有超低功耗,同时还能在主 CPU 处于低功耗模式时保持运行。因此,LP 内核协处理器能够在主 CPU 处于睡眠模式时处理 GPIO 或传感器读取等任务,从而显著降低整个系统的整体功耗。
ULP LP 内核协处理器具有以下功能:
RV32I 处理器(32 位 RISC-V ISA),支持乘法/除法 (M)、原子 (A) 和压缩 (C) 扩展。
中断控制器。
包含一个调试模块,支持通过 JTAG 进行外部调试。
当整个系统处于 active 模式时,可以访问所有的高功耗 (HP) SRAM 和外设。
当 HP 系统处于睡眠模式时,可以访问低功耗 (LP) SRAM 和外设。
编译 ULP LP 内核代码
ULP LP 内核代码会与 ESP-IDF 项目共同编译,生成一个单独的二进制文件,并自动嵌入到主项目的二进制文件中。编译可通过以下两种方式实现:
使用 ulp_embed_binary
将用 C 语言或汇编语言编写的 ULP LP 内核代码(带有
.S
扩展名)放在组件目录下的专用目录中,例如ulp/
。在
CMakeLists.txt
文件中注册组件后,调用ulp_embed_binary
函数。例如:
idf_component_register()
set(ulp_app_name ulp_${COMPONENT_NAME})
set(ulp_sources "ulp/ulp_c_source_file.c" "ulp/ulp_assembly_source_file.S")
set(ulp_exp_dep_srcs "ulp_c_source_file.c")
ulp_embed_binary(${ulp_app_name} "${ulp_sources}" "${ulp_exp_dep_srcs}")
ulp_embed_binary
的第一个参数指定生成的 ULP 二进制文件名。该文件名也用于其他生成的文件,如 ELF 文件、映射文件、头文件和链接器导出文件。第二个参数指定 ULP 源文件。第三个参数指定组件源文件列表,其中包括生成的头文件。此列表用以正确构建依赖,并确保在编译这些文件前创建要生成的头文件。有关 ULP 应用程序生成头文件的概念,请参阅本文档后续章节。
使用自定义的 CMake 项目
也可以为 LP 内核创建自定义的 CMake 项目,从而更好地控制构建过程,并实现常规 CMake 项目的操作,例如设置编译选项、链接外部库等。
请在组件的 CMakeLists.txt
文件中将 ULP 项目添加为外部项目:
ulp_add_project("ULP_APP_NAME" "${CMAKE_SOURCE_DIR}/PATH_TO_DIR_WITH_ULP_PROJECT_FILE/")
请创建一个文件夹,并在文件夹中添加 ULP 项目文件及 CMakeLists.txt
文件,该文件夹的位置应与 ulp_add_project
函数中指定的路径一致。CMakeLists.txt
文件应如下所示:
cmake_minimum_required(VERSION 3.16)
# 项目/目标名称由主项目传递,允许 IDF 依赖此目标
# 将二进制文件嵌入到主应用程序中
project(${ULP_APP_NAME})
add_executable(${ULP_APP_NAME} main.c)
# 导入 ULP 项目辅助函数
include(IDFULPProject)
# 应用默认的编译选项
ulp_apply_default_options(${ULP_APP_NAME})
# 应用 IDF ULP 组件提供的默认源文件
ulp_apply_default_sources(${ULP_APP_NAME})
# 添加构建二进制文件的目标,并添加链接脚本,用于将 ULP 共享变量导出到主应用程序
ulp_add_build_binary_targets(${ULP_APP_NAME})
# 以下内容是可选的,可以用于自定义构建过程
# 创建自定义库
set(lib_path "${CMAKE_CURRENT_LIST_DIR}/lib")
add_library(custom_lib STATIC "${lib_path}/lib_src.c")
target_include_directories(custom_lib PUBLIC "${lib_path}/")
# 链接到库
target_link_libraries(${ULP_APP_NAME} PRIVATE custom_lib)
# 设置自定义编译标志
target_compile_options(${ULP_APP_NAME} PRIVATE -msave-restore)
构建项目
若想编译和构建项目,请执行以下操作:
在 menuconfig 中启用 CONFIG_ULP_COPROC_ENABLED 和 CONFIG_ULP_COPROC_TYPE 选项,并将 CONFIG_ULP_COPROC_TYPE 设置为
CONFIG_ULP_COPROC_TYPE_LP_CORE
。CONFIG_ULP_COPROC_RESERVE_MEM 选项为 ULP 保留 RTC 内存,因此必须设置为一个足够大的值,以存储 ULP LP 内核代码和数据。如果应用程序组件包含多个 ULP 程序,那么 RTC 内存的大小必须足够容纳其中最大的程序。按照常规步骤构建应用程序(例如
idf.py app
)。
在构建过程中,采取以下步骤来构建 ULP 程序:
通过 C 编译器和汇编器运行每个源文件。 此步骤会在组件构建目录中生成目标文件
.obj.c
或.obj.S
,具体取决于处理的源文件。通过 C 预处理器运行链接器脚本模板。 模板位于
components/ulp/ld
目录中。将对象文件链接到一个 ELF 输出文件中, 即
ulp_app_name.elf
。在此阶段生成的映射文件ulp_app_name.map
可用于调试。将 ELF 文件的内容转储到一个二进制文件中, 即
ulp_app_name.bin
。此二进制文件接下来可以嵌入到应用程序中。使用
riscv32-esp-elf-nm
在 ELF 文件中 生成全局符号列表, 即ulp_app_name.sym
。创建一个 LD 导出脚本和一个头文件, 即
ulp_app_name.ld
和ulp_app_name.h
,并在其中包含ulp_app_name.sym
中的符号。此步骤可以通过esp32ulp_mapgen.py
实现。将生成的二进制文件添加到要嵌入到应用程序中的二进制文件列表。
访问 ULP LP 内核程序变量
在主程序中可以使用在 ULP LP 内核程序中定义的全局符号。
例如,ULP LP 内核程序定义了一个变量 measurement_count
,用来表示程序从深度睡眠中唤醒芯片前所需的 GPIO 测量次数。
volatile int measurement_count;
int some_function()
{
//读取测量次数以便后续使用。
int temp = measurement_count;
...do something.
}
主程序可以访问 ULP LP 内核程序全局变量,这是因为构建系统生成了 ${ULP_APP_NAME}.h
和 ${ULP_APP_NAME}.ld
文件,文件中定义了 ULP LP 内核程序中现有的的全局符号。在 ULP LP 内核程序中定义的每个全局符号都包含在这两个文件中,并具有前缀 ulp_
。
头文件中包含符号的声明:
extern uint32_t ulp_measurement_count;
注意,所有的符号(变量、数组、函数)都被声明为 uint32_t
类型。对于函数和数组,获取符号的地址并将其转换为合适的类型。
生成的链接器脚本文件定义了 LP_MEM 中符号的位置:
PROVIDE ( ulp_measurement_count = 0x50000060 );
要从主程序访问 ULP LP 内核程序变量,应使用 include
语句将生成的头文件包含在主程序中,这样就可以像访问常规变量一样访问 ULP LP 内核程序变量。
#include "ulp_app_name.h"
void init_ulp_vars() {
ulp_measurement_count = 64;
}
备注
LP 内核程序全局变量存储在二进制文件的 .bss
或者 .data
部分。这些部分在加载和执行 LP 内核二进制文件时被初始化。在首次运行 LP 内核之前,从 HP-Core 主程序访问这些变量可能会导致未定义行为。
启动 ULP LP 内核程序
要运行 ULP LP 内核程序,主应用程序需要先使用 ulp_lp_core_load_binary()
函数将 ULP 程序加载到 RTC 内存中,然后使用 ulp_lp_core_run()
函数进行启动。
每个 ULP LP 内核程序以二进制 blob 的形式嵌入到 ESP-IDF 应用程序中。应用程序可以按照如下方式引用和加载该 blob(假设 ULP_APP_NAME 被定义为 ulp_app_name
):
extern const uint8_t bin_start[] asm("_binary_ulp_app_name_bin_start");
extern const uint8_t bin_end[] asm("_binary_ulp_app_name_bin_end");
void start_ulp_program() {
ESP_ERROR_CHECK( ulp_lp_core_load_binary( bin_start,
(bin_end - bin_start)) );
}
将程序加载到 LP 内存后,就可以调用 ulp_lp_core_run()
配置和启动应用程序:
ulp_lp_core_cfg_t cfg = {
.wakeup_source = ULP_LP_CORE_WAKEUP_SOURCE_LP_TIMER, // LP 内核会定期被 LP 定时器唤醒
.lp_timer_sleep_duration_us = 10000,
};
ESP_ERROR_CHECK( ulp_lp_core_run(&cfg) );
ULP LP 内核程序流程
ULP LP 内核协处理器如何启动取决于 ulp_lp_core_cfg_t
中选择的唤醒源。最常见的用例是 ULP 定期唤醒,在进行一些测量后唤醒主 CPU,或者再次进入睡眠状态。
- ULP 有以下唤醒源:
ULP_LP_CORE_WAKEUP_SOURCE_HP_CPU
- LP 内核可以被 HP CPU 唤醒。ULP_LP_CORE_WAKEUP_SOURCE_LP_TIMER
- LP 内核可以被 LP 定时器唤醒。ULP_LP_CORE_WAKEUP_SOURCE_ETM
- LP 内核可以被 ETM 事件唤醒。(暂不支持)ULP_LP_CORE_WAKEUP_SOURCE_LP_IO
- 当 LP IO 电平变化时,LP 内核会被唤醒。(暂不支持)ULP_LP_CORE_WAKEUP_SOURCE_LP_UART
- LP 内核在接收到一定数量的 UART RX 脉冲后会被唤醒。(暂不支持)
ULP 被唤醒时会经历以下步骤:
初始化系统功能,如中断
调用用户代码
main()
从
main()
返回如果指定了
lp_timer_sleep_duration_us
,则配置下一个唤醒闹钟
ULP LP 内核支持的外设
为了增强 ULP LP 内核协处理器的功能,它可以访问在低功耗电源域运行的外设。ULP LP 内核协处理器可以在主 CPU 处于睡眠模式时与这些外设进行交互,并在达到唤醒条件时唤醒主 CPU。以下为支持的外设:
LP IO
LP I2C
LP UART
ULP LP 内核中断
配置 LP 内核协处理器,可以处理各种类型的中断,例如 LP IO 低/高电平中断或是 LP 定时器中断。只需重写 IDF 提供的任何一个弱处理函数,就可以注册一个中断处理程序。所有处理程序可见 ulp_lp_core_interrupts.h 。有关特定目标可使用的中断的详细信息,请参阅 ESP32-C6 技术参考手册 [PDF]。
例如,要重写 LP IO 中断的处理程序,可以在 ULP LP 内核代码中定义以下函数:
void LP_CORE_ISR_ATTR ulp_lp_core_lp_io_intr_handler(void)
{
// 处理中断,清除中断源
}
LP_CORE_ISR_ATTR
宏用于定义中断处理函数,可确保调用中断处理程序时妥善保存并恢复寄存器。
除了为需要处理的中断源配置相关的中断寄存器外,还要调用 ulp_lp_core_intr_enable()
函数,在 LP 内核中断控制器中使能全局中断。
ULP LP 内核时钟配置
ULP LP 内核的时钟源来自系统时钟 LP_FAST_CLK
,详情请参见 技术参考手册 > 复位和时钟
。
调试 ULP LP 内核应用程序
在编程 LP 内核时,有时很难弄清楚程序未按预期运行的原因。请参考以下策略,调试 LP 内核程序:
使用 LP-UART 打印:LP 内核可以访问 LP-UART 外设,在主 CPU 处于睡眠状态时独立打印信息。有关使用此驱动程序的示例,请参阅 system/ulp/lp_core/lp_uart/lp_uart_print。
通过 CONFIG_ULP_HP_UART_CONSOLE_PRINT,将
lp_core_printf()
路由到 HP-Core 控制台 UART,可以轻松地将 LP 内核信息打印到已经连接的 HP-Core 控制台 UART。此方法的缺点是需要主 CPU 处于唤醒状态,并且由于 LP 内核与 HP 内未同步,输出可能会交错。通过共享变量共享程序状态:如 访问 ULP LP 内核程序变量 所述,主 CPU 和 ULP 内核都可以轻松访问 RTC 内存中的全局变量。若想了解 ULP 内核的运行状态,可以将状态信息从 ULP 写入变量中,并通过主 CPU 读取信息。这种方法的缺点在于它需要主 CPU 一直处于唤醒状态,而这通常很难实现。另外,若主 CPU 一直处于唤醒状态,可能会掩盖某些问题,因为部分问题只会在特定电源域断电时发生。
紧急处理程序:当检测到异常时,LP 内核的紧急处理程序会把 LP 内核寄存器的状态通过 LP-UART 发送出去。将 CONFIG_ULP_PANIC_OUTPUT_ENABLE 选项设置为
y
,可以启用紧急处理程序。禁用此选项将减少 LP 内核应用程序的 LP-RAM 使用量。若想从紧急转储中解析栈回溯,可以使用 esp-idf-monitor,例如:python -m esp_idf_monitor --toolchain-prefix riscv32-esp-elf- --target ESP32-C6 --decode-panic backtrace PATH_TO_ULP_ELF_FILE
调试 ULP LP 内核应用程序:使用 GDB 和 OpenOCD
与调试 HP 内核类似,也可以用 GDB 和 OpenOCD 来调试 LP 内核上的代码,但要注意其特殊之处和限制条件。
调试会话
使用支持 LP 内核调试的特殊配置文件来运行 OpenOCD,然后用特殊的 gdbinit
文件运行 GDB。
openocd -f board/esp32c6-lpcore-builtin.cfg
riscv32-esp-elf-gdb -x gdbinit <path to main program ELF>
以下是带有内联注释的 gdbinit
文件内容,详细信息请参考下一章节。
# 连接到目标
target extended-remote :3333
# 重置芯片
mon reset halt
maintenance flush register-cache
# 添加 ULP 程序的符号和调试信息
add-symbol <ULP 程序 ELF 文件路径>
# 设置临时硬件断点
# 如果需要的断点数量超过硬件支持的数量
thb main
commands
# 在这里设置断点
# 此时 ULP 程序已加载到 RAM 中
# 若无可用的硬件断点插槽,GDB 将设置软件断点
b func1
b func2
b func3
# 恢复执行
c
end
# 重置后启动主程序
c
LP 内核调试特性
为了方便调试,请在 ULP 应用的
CMakeLists.txt
文件中添加-O0
编译选项。具体操作步骤请参见 system/ulp/lp_core/debugging/。LP 内核支持的硬件异常类型有限,例如,写入地址 0x0 不会像在 HP 内核上一样造成系统崩溃。启用 LP 内核应用程序的未定义行为检测器 (ubsan) 可以捕捉一些错误,从而在一定程度上弥补这一限制。但请注意,这将显著增加代码量,可能会导致应用程序超出 RTC RAM 的容量限制。要启用 ubsan,请在
CMakeLists.txt
文件中添加-fsanitize=undefined -fno-sanitize=shift-base
编译选项。具体操作步骤请参见 system/ulp/lp_core/debugging/。为了调试运行在 LP 内核上的程序,需要先将调试信息和符号加载到 GDB 中。这可以通过 GDB 命令行或在
gdbinit
文件中完成。具体操作步骤请参见上文。LP 内核应用程序会在启时会加载到 RAM 中,在此之前设置的所有软件断点都会被覆盖。设置 LP 内核应用断点的最佳时机是在 LP 内核程序运行至
main
函数之时。使用 IDE 时,可能无法配置上述
gdbinit
文件中的断点操作或命令。因此,请在调试会话开始前预设并禁用所有断点,只保留main
函数处的断点。当程序在main
处停止时,手动启用其余断点并恢复执行。
限制
调试场景有限制:目前,当 HP 内核或 LP 内核进入睡眠模式时,将无法调适。
调试 内核时,OpenOCD 不支持 FreeRTOS,因此无法看到系统中正在运行的任务,但会有几个线程代表 HP 和 LP 内核:
(gdb) info thread
Id Target Id Frame
1 Thread 1 "esp32c6.cpu0" (Name: esp32c6.cpu0, state: debug-request) 0x40803772 in esp_cpu_wait_for_intr ()
at /home/user/projects/esp/esp-idf/components/esp_hw_support/cpu.c:64
* 2 Thread 2 "esp32c6.cpu1" (Name: esp32c6.cpu1, state: breakpoint) do_things (max=1000000000)
at /home/user/projects/esp/esp-idf/examples/system/ulp/lp_core/debugging/main/lp_core/main.c:21
在 GDB 中设置硬件断点时,这些断点会同时应用到两个内核上,因此可用的硬件断点数量受 LP 内核支持数量(ESP32-C6 有 4 个)所限。
OpenOCD 的 flash 支持被禁用。LP 内核应用程序完全在 RAM 中运行,且 GDB 可以为其使用软件断点,因而该限制无关紧要。但若想在 HP 内核运行的代码中调用的 flash 函数(例如 app_main)上设置断点,则需要通过
hb
和thb
GDB 命令显式请求设置硬件断点。由于主程序和 ULP 程序被链接为独立的二进制文件,它们可能会拥有相同名称的全局符号(如函数或变量)。若通过函数名称设置断点,则 GDB 将为所有同名函数设置断点。在调试 LP 内核时,OpenOCD 不支持 flash,因此如果上述函数位于 flash 中,可能会引发问题。此时建议通过源代码行号或函数的内存地址来设置断点。
应用示例
system/ulp/lp_core/gpio 展示了 ULP LP 内核协处理器在主 CPU 深度睡眠时轮询 GPIO。
system/ulp/lp_core/lp_i2c 展示了 ULP LP 内核协处理器在主 CPU 深度睡眠时读取外部 I2C 环境光传感器 (BH1750),并在达到阈值时唤醒主 CPU。
system/ulp/lp_core/lp_uart/lp_uart_echo 展示了低功耗内核上运行的 LP UART 驱动程序如何读取并回显写入串行控制台的数据。
system/ulp/lp_core/lp_uart/lp_uart_print 展示了如何在低功耗内核上使用串口打印功能。
system/ulp/lp_core/interrupt 展示了如何在 LP 内核上注册中断处理程序,接收由主 CPU 触发的中断。
system/ulp/lp_core/gpio_intr_pulse_counter 展示了如何在主 CPU 处于 Deep-sleep 模式时,使用 GPIO 中断为脉冲计数。
system/ulp/lp_core/build_system/ 演示了如何为 ULP 应用程序添加自定义的
CMakeLists.txt
文件。system/ulp/lp_core/debugging 演示了如何使用 GDB 和 OpenOCD 来调试运行在 LP 内核上的代码。
API 参考
主 CPU API 参考
Header File
This header file can be included with:
#include "ulp_lp_core.h"
This header file is a part of the API provided by the
ulp
component. To declare that your component depends onulp
, add the following to your CMakeLists.txt:REQUIRES ulp
or
PRIV_REQUIRES ulp
Functions
-
esp_err_t ulp_lp_core_run(ulp_lp_core_cfg_t *cfg)
Configure the ULP and run the program loaded into RTC memory.
- 返回
ESP_OK on success
-
esp_err_t ulp_lp_core_load_binary(const uint8_t *program_binary, size_t program_size_bytes)
Load the program binary into RTC memory.
- 参数
program_binary -- pointer to program binary
program_size_bytes -- size of the program binary
- 返回
ESP_OK on success
ESP_ERR_INVALID_SIZE if program_size_bytes is more than KiB
-
void ulp_lp_core_stop(void)
Puts the ulp to sleep and disables all wakeup sources. To restart the ULP call ulp_lp_core_run() with the desired wake up trigger.
-
void ulp_lp_core_sw_intr_trigger(void)
Trigger a SW interrupt to the LP CPU from the PMU.
备注
This is the same SW trigger that is used to wake up the LP CPU
Structures
-
struct ulp_lp_core_cfg_t
ULP LP core init parameters.
Macros
-
ULP_LP_CORE_WAKEUP_SOURCE_HP_CPU
-
ULP_LP_CORE_WAKEUP_SOURCE_LP_UART
-
ULP_LP_CORE_WAKEUP_SOURCE_LP_IO
-
ULP_LP_CORE_WAKEUP_SOURCE_ETM
-
ULP_LP_CORE_WAKEUP_SOURCE_LP_TIMER
-
ULP_LP_CORE_WAKEUP_SOURCE_LP_VAD
Header File
This header file can be included with:
#include "lp_core_i2c.h"
This header file is a part of the API provided by the
ulp
component. To declare that your component depends onulp
, add the following to your CMakeLists.txt:REQUIRES ulp
or
PRIV_REQUIRES ulp
Functions
-
esp_err_t lp_core_i2c_master_init(i2c_port_t lp_i2c_num, const lp_core_i2c_cfg_t *cfg)
Initialize and configure the LP I2C for use by the LP core Currently LP I2C can only be used in master mode.
备注
The internal pull-up resistors for SDA and SCL pins, if enabled, will provide a weak pull-up value of about 30-50 kOhm. Users are adviced to enable external pull-ups for better performance at higher SCL frequencies.
- 参数
lp_i2c_num -- LP I2C port number
cfg -- Configuration parameters
- 返回
esp_err_t ESP_OK when successful
Structures
-
struct lp_core_i2c_pin_cfg_t
LP Core I2C pin config parameters.
Public Members
-
gpio_num_t sda_io_num
GPIO pin for SDA signal. Only GPIO#6 can be used as the SDA pin.
-
gpio_num_t scl_io_num
GPIO pin for SCL signal. Only GPIO#7 can be used as the SCL pin.
-
bool sda_pullup_en
SDA line enable internal pullup. Can be configured if external pullup is not used.
-
bool scl_pullup_en
SCL line enable internal pullup. Can be configured if external pullup is not used.
-
gpio_num_t sda_io_num
-
struct lp_core_i2c_timing_cfg_t
LP Core I2C timing config parameters.
Public Members
-
uint32_t clk_speed_hz
LP I2C clock speed for master mode
-
uint32_t clk_speed_hz
-
struct lp_core_i2c_cfg_t
LP Core I2C config parameters.
Public Members
-
lp_core_i2c_pin_cfg_t i2c_pin_cfg
LP I2C pin configuration
-
lp_core_i2c_timing_cfg_t i2c_timing_cfg
LP I2C timing configuration
-
soc_periph_lp_i2c_clk_src_t i2c_src_clk
LP I2C source clock type
-
lp_core_i2c_pin_cfg_t i2c_pin_cfg
Macros
-
LP_I2C_DEFAULT_GPIO_CONFIG()
-
LP_I2C_FAST_MODE_CONFIG()
-
LP_I2C_STANDARD_MODE_CONFIG()
-
LP_I2C_DEFAULT_SRC_CLK()
-
LP_CORE_I2C_DEFAULT_CONFIG()
Header File
This header file can be included with:
#include "lp_core_uart.h"
This header file is a part of the API provided by the
ulp
component. To declare that your component depends onulp
, add the following to your CMakeLists.txt:REQUIRES ulp
or
PRIV_REQUIRES ulp
Functions
-
esp_err_t lp_core_uart_init(const lp_core_uart_cfg_t *cfg)
Initialize and configure the LP UART to be used from the LP core.
备注
The LP UART initialization must be called from the main core (HP CPU)
- 参数
cfg -- Configuration parameters
- 返回
esp_err_t ESP_OK when successful
Structures
-
struct lp_core_uart_pin_cfg_t
LP UART IO pins configuration.
Public Members
-
gpio_num_t tx_io_num
GPIO pin for UART Tx signal. Only GPIO#5 can be used as the UART Tx pin
-
gpio_num_t rx_io_num
GPIO pin for UART Rx signal. Only GPIO#4 can be used as the UART Rx pin
-
gpio_num_t rts_io_num
GPIO pin for UART RTS signal. Only GPIO#2 can be used as the UART RTS pin
-
gpio_num_t cts_io_num
GPIO pin for UART CTS signal. Only GPIO#3 can be used as the UART CTS pin
-
gpio_num_t tx_io_num
-
struct lp_core_uart_proto_cfg_t
LP UART protocol configuration.
Public Members
-
int baud_rate
LP UART baud rate
-
uart_word_length_t data_bits
LP UART byte size
-
uart_parity_t parity
LP UART parity mode
-
uart_stop_bits_t stop_bits
LP UART stop bits
-
uart_hw_flowcontrol_t flow_ctrl
LP UART HW flow control mode (cts/rts)
-
uint8_t rx_flow_ctrl_thresh
LP UART HW RTS threshold
-
int baud_rate
-
struct lp_core_uart_cfg_t
LP UART configuration parameters.
Public Members
-
lp_core_uart_pin_cfg_t uart_pin_cfg
LP UART pin configuration
-
lp_core_uart_proto_cfg_t uart_proto_cfg
LP UART protocol configuration
-
lp_uart_sclk_t lp_uart_source_clk
LP UART source clock selection
-
lp_core_uart_pin_cfg_t uart_pin_cfg
Macros
-
LP_UART_DEFAULT_TX_GPIO_NUM
Default LP_IO Mux pins for LP UART
-
LP_UART_DEFAULT_RX_GPIO_NUM
-
LP_UART_DEFAULT_RTS_GPIO_NUM
-
LP_UART_DEFAULT_CTS_GPIO_NUM
-
LP_UART_DEFAULT_GPIO_CONFIG()
-
LP_UART_DEFAULT_PROTO_CONFIG()
-
LP_UART_DEFAULT_CLOCK_CONFIG()
-
LP_CORE_UART_DEFAULT_CONFIG()
Header File
This header file can be included with:
#include "lp_core_etm.h"
This header file is a part of the API provided by the
ulp
component. To declare that your component depends onulp
, add the following to your CMakeLists.txt:REQUIRES ulp
or
PRIV_REQUIRES ulp
Functions
-
esp_err_t lp_core_new_etm_event(const lp_core_etm_event_config_t *config, esp_etm_event_handle_t *out_event)
Create a ETM event for LP-Core.
备注
The created ETM event object can be deleted later by calling
esp_etm_del_event
- 参数
config -- [in] LP-Core ETM event configuration
out_event -- [out] Returned ETM event handle
- 返回
ESP_OK: Get ETM event successfully
ESP_ERR_INVALID_ARG: Get ETM event failed because of invalid argument
ESP_FAIL: Get ETM event failed because of other error
-
esp_err_t lp_core_new_etm_task(const lp_core_etm_task_config_t *config, esp_etm_task_handle_t *out_task)
Create a ETM task for LP-Core.
备注
The created ETM task object can be deleted later by calling
esp_etm_del_task
- 参数
config -- [in] LP-Core ETM task configuration
out_task -- [out] Returned ETM task handle
- 返回
ESP_OK: Get ETM task successfully
ESP_ERR_INVALID_ARG: Get ETM task failed because of invalid argument
ESP_FAIL: Get ETM task failed because of other error
Structures
-
struct lp_core_etm_event_config_t
LP-Core ETM event configuration.
Public Members
-
lp_core_etm_event_type_t event_type
LP-Core ETM event type
-
lp_core_etm_event_type_t event_type
-
struct lp_core_etm_task_config_t
LP-Core ETM task configuration.
Public Members
-
lp_core_etm_task_type_t task_type
LP-Core ETM task type
-
lp_core_etm_task_type_t task_type
Header File
This header file can be included with:
#include "hal/lp_core_types.h"
Enumerations
LP 内核 API 参考
Header File
Functions
-
void ulp_lp_core_update_wakeup_cause(void)
Traverse all possible wake-up sources and update the wake-up cause so that ulp_lp_core_get_wakeup_cause can obtain the bitmap of the wake-up reasons.
-
uint32_t ulp_lp_core_get_wakeup_cause(void)
Get the wakeup source which caused LP_CPU to wakeup from sleep.
- 返回
Wakeup cause in bit map, for the meaning of each bit, refer to the definition of wakeup source in lp_core_ll.h
-
void ulp_lp_core_wakeup_main_processor(void)
Wakeup main CPU from sleep or deep sleep.
This raises a software interrupt signal, if the main CPU has configured the ULP as a wakeup source calling this function will make the main CPU to exit from sleep or deep sleep.
-
void ulp_lp_core_delay_us(uint32_t us)
Makes the co-processor busy wait for a certain number of microseconds.
- 参数
us -- Number of microseconds to busy-wait for
-
void ulp_lp_core_delay_cycles(uint32_t cycles)
Makes the co-processor busy wait for a certain number of cycles.
- 参数
cycles -- Number of cycles to busy-wait for
-
void ulp_lp_core_halt(void)
Finishes the ULP program and powers down the ULP until next wakeup.
备注
This function does not return. After called it will fully reset the ULP.
备注
The program will automatically call this function when returning from main().
备注
To stop the ULP from waking up, call ulp_lp_core_lp_timer_disable() before halting.
-
void ulp_lp_core_stop_lp_core(void)
The LP core puts itself to sleep and disables all wakeup sources.
-
void ulp_lp_core_abort(void)
Abort LP core operation.
-
void ulp_lp_core_sw_intr_enable(bool enable)
Enable the SW triggered interrupt from the PMU.
备注
This is the same SW trigger interrupt that is used to wake up the LP CPU
- 参数
enable -- true to enable, false to disable
-
void ulp_lp_core_sw_intr_clear(void)
Clear the interrupt status for the SW triggered interrupt from the PMU.
-
void ulp_lp_core_wait_for_intr(void)
Puts the CPU into a wait state until an interrupt is triggered.
备注
The CPU will draw less power when in this state compared to actively running
Header File
Functions
-
static inline void ulp_lp_core_gpio_init(lp_io_num_t lp_io_num)
Initialize a rtcio pin.
备注
If IO is used in LP application,
rtc_gpio_init
must be called at least once for the using IO before loading LP core firmware in HP Code.- 参数
lp_io_num -- The rtc io pin to initialize
-
static inline void ulp_lp_core_gpio_output_enable(lp_io_num_t lp_io_num)
Enable output.
- 参数
lp_io_num -- The rtc io pin to enable output for
-
static inline void ulp_lp_core_gpio_output_disable(lp_io_num_t lp_io_num)
Disable output.
- 参数
lp_io_num -- The rtc io pin to disable output for
-
static inline void ulp_lp_core_gpio_input_enable(lp_io_num_t lp_io_num)
Enable input.
- 参数
lp_io_num -- The rtc io pin to enable input for
-
static inline void ulp_lp_core_gpio_input_disable(lp_io_num_t lp_io_num)
Disable input.
- 参数
lp_io_num -- The rtc io pin to disable input for
-
static inline void ulp_lp_core_gpio_set_level(lp_io_num_t lp_io_num, uint8_t level)
Set rtcio output level.
- 参数
lp_io_num -- The rtc io pin to set the output level for
level -- 0: output low; 1: output high.
-
static inline uint32_t ulp_lp_core_gpio_get_level(lp_io_num_t lp_io_num)
Get rtcio output level.
- 参数
lp_io_num -- The rtc io pin to get the output level for
-
static inline void ulp_lp_core_gpio_set_output_mode(lp_io_num_t lp_io_num, rtcio_ll_out_mode_t mode)
Set rtcio output mode.
- 参数
lp_io_num -- The rtc io pin to set the output mode for
mode -- RTCIO_LL_OUTPUT_NORMAL: normal, RTCIO_LL_OUTPUT_OD: open drain
-
static inline void ulp_lp_core_gpio_pullup_enable(lp_io_num_t lp_io_num)
Enable internal pull-up resistor.
- 参数
lp_io_num -- The rtc io pin to enable pull-up for
-
static inline void ulp_lp_core_gpio_pullup_disable(lp_io_num_t lp_io_num)
Disable internal pull-up resistor.
- 参数
lp_io_num -- The rtc io pin to disable pull-up for
-
static inline void ulp_lp_core_gpio_pulldown_enable(lp_io_num_t lp_io_num)
Enable internal pull-down resistor.
- 参数
lp_io_num -- The rtc io pin to enable pull-down for
-
static inline void ulp_lp_core_gpio_pulldown_disable(lp_io_num_t lp_io_num)
Disable internal pull-down resistor.
- 参数
lp_io_num -- The rtc io pin to disable pull-down for
-
static inline void ulp_lp_core_gpio_intr_enable(lp_io_num_t lp_io_num, lp_io_intr_type_t intr_type)
Enable interrupt for lp io pin.
- 参数
lp_io_num -- The lp io pin to enable interrupt for
intr_type -- The interrupt type to enable
-
static inline void ulp_lp_core_gpio_clear_intr_status(void)
Clear interrupt status for all lp io.
Macros
-
RTCIO_OUTPUT_NORMAL
-
RTCIO_OUTPUT_OD
Enumerations
-
enum lp_io_num_t
Values:
-
enumerator LP_IO_NUM_0
GPIO0, input and output
-
enumerator LP_IO_NUM_1
GPIO1, input and output
-
enumerator LP_IO_NUM_2
GPIO2, input and output
-
enumerator LP_IO_NUM_3
GPIO3, input and output
-
enumerator LP_IO_NUM_4
GPIO4, input and output
-
enumerator LP_IO_NUM_5
GPIO5, input and output
-
enumerator LP_IO_NUM_6
GPIO6, input and output
-
enumerator LP_IO_NUM_7
GPIO7, input and output
-
enumerator LP_IO_NUM_0
-
enum lp_io_intr_type_t
Values:
-
enumerator LP_IO_INTR_DISABLE
Disable GPIO interrupt
-
enumerator LP_IO_INTR_POSEDGE
GPIO interrupt type : rising edge
-
enumerator LP_IO_INTR_NEGEDGE
GPIO interrupt type : falling edge
-
enumerator LP_IO_INTR_ANYEDGE
GPIO interrupt type : both rising and falling edge
-
enumerator LP_IO_INTR_LOW_LEVEL
GPIO interrupt type : input low level trigger
-
enumerator LP_IO_INTR_HIGH_LEVEL
GPIO interrupt type : input high level trigger
-
enumerator LP_IO_INTR_DISABLE
Header File
Functions
-
esp_err_t lp_core_i2c_master_read_from_device(i2c_port_t lp_i2c_num, uint16_t device_addr, uint8_t *data_rd, size_t size, int32_t ticks_to_wait)
Read from I2C device.
备注
The LP I2C must have been initialized from the HP core using the lp_core_i2c_master_init() API before invoking this API.
备注
the LP I2C does not support 10-bit I2C device addresses.
备注
the LP I2C port number is ignored at the moment.
- 参数
lp_i2c_num -- LP I2C port number
device_addr -- I2C device address (7-bit)
data_rd -- Buffer to hold data to be read
size -- Size of data to be read in bytes
ticks_to_wait -- Operation timeout in CPU cycles. Set to -1 to wait forever.
- 返回
esp_err_t ESP_OK when successful
-
esp_err_t lp_core_i2c_master_write_to_device(i2c_port_t lp_i2c_num, uint16_t device_addr, const uint8_t *data_wr, size_t size, int32_t ticks_to_wait)
Write to I2C device.
备注
The LP I2C must have been initialized from the HP core using the lp_core_i2c_master_init() API before invoking this API.
备注
the LP I2C does not support 10-bit I2C device addresses.
备注
the LP I2C port number is ignored at the moment.
- 参数
lp_i2c_num -- LP I2C port number
device_addr -- I2C device address (7-bit)
data_wr -- Buffer which holds the data to be written
size -- Size of data to be written in bytes
ticks_to_wait -- Operation timeout in CPU cycles. Set to -1 to wait forever.
- 返回
esp_err_t ESP_OK when successful
-
esp_err_t lp_core_i2c_master_write_read_device(i2c_port_t lp_i2c_num, uint16_t device_addr, const uint8_t *data_wr, size_t write_size, uint8_t *data_rd, size_t read_size, int32_t ticks_to_wait)
Write to and then read from an I2C device in a single transaction.
备注
The LP I2C must have been initialized from the HP core using the lp_core_i2c_master_init() API before invoking this API.
备注
the LP I2C does not support 10-bit I2C device addresses.
备注
the LP I2C port number is ignored at the moment.
- 参数
lp_i2c_num -- LP I2C port number
device_addr -- I2C device address (7-bit)
data_wr -- Buffer which holds the data to be written
write_size -- Size of data to be written in bytes
data_rd -- Buffer to hold data to be read
read_size -- Size of data to be read in bytes
ticks_to_wait -- Operation timeout in CPU cycles. Set to -1 to wait forever.
- 返回
esp_err_t ESP_OK when successful
-
void lp_core_i2c_master_set_ack_check_en(i2c_port_t lp_i2c_num, bool ack_check_en)
Enable or disable ACK checking by the LP_I2C controller during write operations.
When ACK checking is enabled, the hardware will check the ACK/NACK level received during write operations against the expected ACK/NACK level. If the received ACK/NACK level does not match the expected ACK/NACK level then the hardware will generate the I2C_NACK_INT and a STOP condition will be generated to stop the data transfer.
备注
ACK checking is enabled by default
备注
the LP I2C port number is ignored at the moment.
- 参数
lp_i2c_num -- LP I2C port number
ack_check_en -- true: enable ACK check false: disable ACK check
Header File
Functions
-
int lp_core_uart_tx_chars(uart_port_t lp_uart_num, const void *src, size_t size)
Send data to the LP UART port if there is space available in the Tx FIFO.
This function will not wait for enough space in the Tx FIFO to be available. It will just fill the available Tx FIFO slots and return when the FIFO is full. If there are no empty slots in the Tx FIFO, this function will not write any data.
- 参数
lp_uart_num -- LP UART port number
src -- data buffer address
size -- data length to send
- 返回
- (-1) Error
OTHERS (>=0) The number of bytes pushed to the Tx FIFO
-
esp_err_t lp_core_uart_write_bytes(uart_port_t lp_uart_num, const void *src, size_t size, int32_t timeout)
Write data to the LP UART port.
This function will write data to the Tx FIFO. If a timeout value is configured, this function will timeout once the number of CPU cycles expire.
- 参数
lp_uart_num -- LP UART port number
src -- data buffer address
size -- data length to send
timeout -- Operation timeout in CPU cycles. Set to -1 to wait forever.
- 返回
esp_err_t ESP_OK when successful
-
int lp_core_uart_read_bytes(uart_port_t lp_uart_num, void *buf, size_t size, int32_t timeout)
Read data from the LP UART port.
This function will read data from the Rx FIFO. If a timeout value is configured, then this function will timeout once the number of CPU cycles expire.
- 参数
lp_uart_num -- LP UART port number
buf -- data buffer address
size -- data length to send
timeout -- Operation timeout in CPU cycles. Set to -1 to wait forever.
- 返回
- (-1) Error
OTHERS (>=0) The number of bytes read from the Rx FIFO
-
void lp_core_uart_tx_flush(uart_port_t lp_uart_num)
Flush LP UART Tx FIFO.
This function is automatically called before the LP core powers down once the main() function returns. It can also be called manually in the application to flush the Tx FIFO.
- 参数
lp_uart_num -- LP UART port number
Header File
Functions
-
void lp_core_printf(const char *format, ...)
Print from the LP core.
备注
This function uses the LP UART peripheral to enable prints.The LP UART must be initialized with lp_core_uart_init() before using this function.
备注
This function is not a standard printf function and may not support all format specifiers or special characters.
- 参数
format -- string to be printed
... -- variable argument list
-
void lp_core_print_char(char c)
Print a single character from the LP core.
- 参数
c -- character to be printed
-
void lp_core_print_str(const char *str)
Print a null-terminated string from the LP core.
- 参数
str -- null-terminated string to be printed
-
void lp_core_print_hex(int h)
Print a hex value from the LP core.
备注
Does not print '0x', only the digits (will always print 8 digits)
- 参数
h -- hex value to be printed
-
void lp_core_print_dec_two_digits(int d)
Print a two digit integer from the LP-Core.
- 参数
d -- integer to be printed
Header File
Functions
-
void ulp_lp_core_intr_enable(void)
Enables interrupts globally for the low power core.
Available interrupt handlers for the low power core are as follows:
ulp_lp_core_lp_io_intr_handler(void); ulp_lp_core_lp_i2c_intr_handler(void); ulp_lp_core_lp_uart_intr_handler(void); ulp_lp_core_lp_timer_intr_handler(void); ulp_lp_core_lp_pmu_intr_handler(void); ulp_lp_core_lp_spi_intr_handler(void); ulp_lp_core_trng_intr_handler(void); ulp_lp_core_lp_adc_intr_handler(void); ulp_lp_core_lp_touch_intr_handler(void); ulp_lp_core_tsens_intr_handler(void); ulp_lp_core_efuse_intr_handler(void); ulp_lp_core_lp_sysreg_intr_handler(void); ulp_lp_core_lp_ana_peri_intr_handler(void); ulp_lp_core_mailbox_intr_handler(void); ulp_lp_core_lp_wdt_intr_handler(void); ulp_lp_core_lp_rtc_intr_handler(void); ulp_lp_core_sw_intr_handler(void);
Not all handlers are available on all chips. Please refer to the Technical Reference Manual for your chip for more information.
-
void ulp_lp_core_intr_disable(void)
Disables interrupts globally for the low power core.
Macros
-
LP_CORE_ISR_ATTR