esp-idf/examples/peripherals/spi_slave
Michael (XIAO Xufeng) 562af8f65e global: move the soc component out of the common list
This MR removes the common dependency from every IDF components to the SOC component.

Currently, in the ``idf_functions.cmake`` script, we include the header path of SOC component by default for all components.
But for better code organization (or maybe also benifits to the compiling speed), we may remove the dependency to SOC components for most components except the driver and kernel related components.

In CMAKE, we have two kinds of header visibilities (set by include path visibility):

(Assume component A --(depends on)--> B, B is the current component)

1. public (``COMPONENT_ADD_INCLUDEDIRS``): means this path is visible to other depending components (A) (visible to A and B)
2. private (``COMPONENT_PRIV_INCLUDEDIRS``): means this path is only visible to source files inside the component (visible to B only)

and we have two kinds of depending ways:

(Assume component A --(depends on)--> B --(depends on)--> C, B is the current component)

1. public (```COMPONENT_REQUIRES```): means B can access to public include path of C. All other components rely on you (A) will also be available for the public headers. (visible to A, B)
2. private (``COMPONENT_PRIV_REQUIRES``): means B can access to public include path of C, but don't propagate this relation to other components (A). (visible to B)

1. remove the common requirement in ``idf_functions.cmake``, this makes the SOC components invisible to all other components by default.
2. if a component (for example, DRIVER) really needs the dependency to SOC, add a private dependency to SOC for it.
3. some other components that don't really depends on the SOC may still meet some errors saying "can't find header soc/...", this is because it's depended component (DRIVER) incorrectly include the header of SOC in its public headers. Moving all this kind of #include into source files, or private headers
4. Fix the include requirements for some file which miss sufficient #include directives. (Previously they include some headers by the long long long header include link)

This is a breaking change. Previous code may depends on the long include chain.
You may need to include the following headers for some files after this commit:

- soc/soc.h
- soc/soc_memory_layout.h
- driver/gpio.h
- esp_sleep.h

The major broken include chain includes:

1. esp_system.h no longer includes esp_sleep.h. The latter includes driver/gpio.h and driver/touch_pad.h.
2. ets_sys.h no longer includes soc/soc.h
3. freertos/portmacro.h no longer includes soc/soc_memory_layout.h

some peripheral headers no longer includes their hw related headers, e.g. rom/gpio.h no longer includes soc/gpio_pins.h and soc/gpio_reg.h

BREAKING CHANGE
2019-04-16 13:21:15 +08:00
..
receiver global: move the soc component out of the common list 2019-04-16 13:21:15 +08:00
sender separate rom from esp32 component to esp_rom 2019-03-21 18:51:45 +08:00
README.md Added / corrected README files for the SPI master / slave examples under peripherals 2018-03-12 05:56:35 +01:00

SPI slave example

These two projects illustrate the SPI Slave driver. They're supposed to be flashed into two separate ESP32s connected to eachother using the SPI pins defined in app_main.c. Once connected and flashed, they will use the spi master and spi slave driver to communicate with eachother. The example also includes a handshaking line to allow the master to only poll the slave when it is actually ready to parse a transaction.

Please run wires between the following GPIOs between the slave and master to make the example function:

Signal Slave Master
Handshake GPIO2 GPIO2
MOSI GPIO12 GPIO12
MISO GPIO13 GPIO13
SCLK GPIO15 GPIO15
CS GPIO14 GPIO14

Be aware that the example by default uses lines normally reserved for JTAG. If this is an issue, either because of hardwired JTAG hardware or because of the need to do JTAG debugging, feel free to change the GPIO settings by editing defines in the top of main.c in the master/slave source code.