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cpu/esp32: add ESP32-S2 support in doc

This commit is contained in:
Gunar Schorcht 2022-06-14 13:29:26 +02:00
parent 0d555de986
commit 53376ce2d3
2 changed files with 391 additions and 7 deletions

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@ -97,7 +97,7 @@ Parameter | Short Description
[ADC_GPIOS](#esp32_adc_channels) | GPIOs that can be used as ADC channels | m
[CAN_TX](#esp32_can_interfaces) | GPIO used as CAN transceiver TX signal | o
[CAN_RX](#esp32_can_interfaces) | GPIO used as CAN transceiver RX signal | o
[DAC_GPIOS](#esp32_adc_channels) | GPIOs that can be used as DAC channels | m
[DAC_GPIOS](#esp32_dac_channels) | GPIOs that can be used as DAC channels | m
[I2C0_SPEED](#esp32_i2c_interfaces) | Bus speed of I2C_DEV(0) | o
[I2C0_SCL](#esp32_i2c_interfaces) | GPIO used as SCL for I2C_DEV(0) | o
[I2C0_SDA](#esp32_i2c_interfaces) | GPIO used as SCL for I2C_DEV(0 | o
@ -167,7 +167,7 @@ either based on
- Tensilica Xtensa 32-bit LX7 microprocessor (ESP32-S2, ESP32-S3), or
- 32-bit RISC-V CPU (ESP32-C3, ESP32-H2).
At the moment, ESP32, ESP32-S3 and ESP32-C3 variants (families) are supported by RIOT-OS.
At the moment, ESP32, ESP32-S2, ESP32-S3 and ESP32-C3 variants (families) are supported by RIOT-OS.
@note Even if the used ESP32x SoC is a dual-core version, RIOT-OS uses only
one core.
@ -252,6 +252,42 @@ The key features of ESP32-C3 are:
</center><br>
### Features of The ESP32-S2 SoC variant (family)
The key features of ESP32-S2 are:
<center>
| MCU | ESP32-S2 | Supported by RIOT |
| ------------------|-------------------------------------------------------------------|------------------ |
| Vendor | Espressif | |
| Cores | 1 x Tensilica Xtensa LX7 | 1 core |
| FPU | ULP - Ultra low power co-processor | no |
| RAM | 320 KiB SRAM <br> 8 KiB slow RTC SRAM <br> 8 KiB fast RTC SRAM | yes <br> yes <br> yes |
| ROM | 128 KiB | yes |
| Flash | 512 KiB ... 32 MiB Dual/Quad/Octal SPI (external or internal) | yes |
| Frequency | 240 MHz, 160 MHz, 80 MHz | yes |
| Power Consumption | 66 mA @ 240 MHz <br> 50 mA @ 160 MHz (40 mA @ 160 MHz single core) <br> 33 mA @ 80 MHz (28 mA @ 80 MHz single core) <br> 19 mA @ 40 MHz (16 mA @ 40 MHz single core) <br>240 uA in light sleep mode <br> 8 uA in deep sleep mode | yes <br> yes <br> yes <br> yes <br> yes <br> yes |
| Timers | 4 x 54 bit | yes |
| ADCs | 2 x SAR-ADC with up to 20 x 13 bit channels total | yes |
| DACs | 2 x DAC with 8 bit | - |
| GPIOs | 43 (22 are RTC GPIOs) | yes |
| I2Cs | 2 | yes |
| SPIs | 4 | yes (2) |
| UARTs | 2 | yes |
| WiFi | IEEE 802.11 b/g/n built in | yes |
| Bluetooth | - | - |
| Ethernet | - | - |
| CAN | version 2.0 | yes |
| IR | up to 4 channels TX/RX | no |
| Motor PWM | 2 devices x 6 channels | no |
| LED PWM | 8 channels with 14 bit resolution in 1 channel group with 4 timers | yes |
| Crypto | Hardware acceleration of AES, SHA-2, RSA, ECC, RNG | no |
| Vcc | 2.8 - 3.6 V | |
| Documents | [Datasheet](https://www.espressif.com/sites/default/files/documentation/esp32-s2_datasheet_en.pdf) <br> [Technical Reference](https://www.espressif.com/sites/default/files/documentation/esp32-s2_technical_reference_manual_en.pdf) | |
</center><br>
### Features of The ESP32-S3 SoC variant (family)
The key features of ESP32-S3 are:
@ -299,6 +335,10 @@ Most common modules used by ESP32x SoC boards are:
- [ESP32-WROVER](https://www.espressif.com/sites/default/files/documentation/esp32-wrover_datasheet_en.pdf)
- [ESP32-C3-MINI-1](https://www.espressif.com/sites/default/files/documentation/esp32-c3-mini-1_datasheet_en.pdf)
- [ESP32-C3-WROOM-02](https://www.espressif.com/sites/default/files/documentation/esp32-c3-wroom-02_datasheet_en.pdf)
- [ESP32-S2-MINI-1](https://www.espressif.com/sites/default/files/documentation/esp32-s2-mini-1_esp32-s2-mini-1u_datasheet_en.pdf)
- [ESP32-S2-SOLO](https://www.espressif.com/sites/default/files/documentation/esp32-s2-solo_esp32-s2-solo-u_datasheet_en.pdf)
- [ESP32-S2-WROOM](https://www.espressif.com/sites/default/files/documentation/esp32-s2-wroom_esp32-s2-wroom-i_datasheet_en.pdf)
- [ESP32-S2-WROVER](https://www.espressif.com/sites/default/files/documentation/esp32-s2-wrover_esp32-s2-wrover-i_datasheet_en.pdf)
- [ESP32-S3-MINI-1](https://www.espressif.com/sites/default/files/documentation/esp32-s3-mini-1_mini-1u_datasheet_en.pdf)
- [ESP32-S3-WROOM-1](https://www.espressif.com/sites/default/files/documentation/esp32-s3-wroom-1_wroom-1u_datasheet_en.pdf)
- [ESP32-S3-WROOM-2](https://www.espressif.com/sites/default/files/documentation/esp32-s3-wroom-2_datasheet_en.pdf)
@ -429,8 +469,8 @@ toolchain (Debian/Ubuntu package names):
The shell script `$RIOTBASE/dist/tools/esptools/install.sh` is used to
install Espressif's precompiled versions of the following tools:
- ESP32 vendor toolchain (for ESP32, ESP32-S3 and ESP32-C3)
- OpenOCD for ESP32 (for ESP32, ESP32-S3 and ESP32-C3)
- ESP32 vendor toolchain (for ESP32, ESP32-S2, ESP32-S3 and ESP32-C3)
- OpenOCD for ESP32 (for ESP32, ESP32-S2, ESP32-S3 and ESP32-C3)
- QEMU for ESP32 (only for ESP32)
`$RIOTBASE` defines the root directory of the RIOT repository. The shell
@ -440,7 +480,7 @@ script takes an argument that specifies which tools to download and install:
$ dist/tools/esptools/install.sh
install.sh <tool>
tool = all | esp32 | esp32c3 | esp32s3 | openocd | qemu
tool = all | esp32 | esp32c3 | esp32s2 | esp32s3 | openocd | qemu
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Thus, either all tools or only certain tools can be installed.
@ -467,7 +507,7 @@ paths of the installed tools using again the environment variable
$ . dist/tools/esptools/export.sh
Usage: export.sh <tool>
tool = all | esp32 | esp32c3 | esp32s3 | openocd | qemu
tool = all | esp32 | esp32c3 | esp32s2 | esp32s3 | openocd | qemu
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
All the tools required for building a RIOT application for ESP32x SoCs should then
@ -604,6 +644,7 @@ always use `dio` or `dout` to keep them free for other purposes:
- ESP32 GPIO9 and GPIO10
- ESP32-C3 GPIO12 and GPIO13
- ESP32-S2 GPIO27 and GPIO28
- ESP32-S3 GPIO27 and GPIO28
For more information about these flash modes, refer the documentation of
@ -690,6 +731,7 @@ For details, see:
- \ref esp32_gpio_pins_esp32 "ESP32"
- \ref esp32_gpio_pins_esp32c3 "ESP32-C3"
- \ref esp32_gpio_pins_esp32s2 "ESP32-S2"
- \ref esp32_gpio_pins_esp32s3 "ESP32-S3"
[Back to table of contents](#esp32_toc)
@ -703,6 +745,7 @@ details, see:
- \ref esp32_adc_channels_esp32 "ESP32"
- \ref esp32_adc_channels_esp32c3 "ESP32-C3"
- \ref esp32_adc_channels_esp32s2 "ESP32-S2"
- \ref esp32_adc_channels_esp32s3 "ESP32-S3"
#ADC_GPIOS in the board-specific peripheral configuration defines the
@ -761,6 +804,7 @@ For the GPIO that can be used with this function, see:
- \ref esp32_adc_channels_esp32 "ESP32"
- \ref esp32_adc_channels_esp32c3 "ESP32-C3"
- \ref esp32_adc_channels_esp32s2 "ESP32-S2"
- \ref esp32_adc_channels_esp32s3 "ESP32-S3"
@note ADC2 is also used by the WiFi module. The GPIOs connected to ADC2 are
@ -835,6 +879,7 @@ on used ESP32x SoC family, for details see:
- \ref esp32_i2c_interfaces_esp32 "ESP32"
- \ref esp32_i2c_interfaces_esp32c3 "ESP32-C3"
- \ref esp32_i2c_interfaces_esp32s2 "ESP32-S2"
- \ref esp32_i2c_interfaces_esp32s3 "ESP32-S3"
@note
@ -886,6 +931,7 @@ channel depends on respective ESP32x SoC family. For details, see:
- \ref esp32_pwm_channels_esp32 "ESP32"
- \ref esp32_pwm_channels_esp32c3 "ESP32-C3"
- \ref esp32_pwm_channels_esp32s2 "ESP32-S2"
- \ref esp32_pwm_channels_esp32s3 "ESP32-S3"
Each channel group has 4 timers which can be used as clock source by the
@ -1007,6 +1053,7 @@ on used ESP32x SoC family, for details see:
- \ref esp32_spi_interfaces_esp32 "ESP32"
- \ref esp32_spi_interfaces_esp32c3 "ESP32-C3"
- \ref esp32_spi_interfaces_esp32s2 "ESP32-S2"
- \ref esp32_spi_interfaces_esp32s3 "ESP32-S3"
@note
@ -1050,6 +1097,7 @@ ESP32x SoC family, for details see:
- \ref esp32_timers_esp32 "ESP32"
- \ref esp32_timers_esp32c3 "ESP32-C3"
- \ref esp32_timers_esp32s2 "ESP32-S2"
- \ref esp32_timers_esp32s3 "ESP32-S3"
Timers are MCU built-in features and not board-specific. There is nothing to
@ -1111,6 +1159,7 @@ on used ESP32x SoC family, for details see:
- \ref esp32_uart_interfaces_esp32 "ESP32"
- \ref esp32_uart_interfaces_esp32c3 "ESP32-C3"
- \ref esp32_uart_interfaces_esp32s2 "ESP32-S2"
- \ref esp32_uart_interfaces_esp32s3 "ESP32-S3"
@note To ensure that the `UARTn_*` symbols define the configuration for
@ -1891,6 +1940,7 @@ For details, see:
- \ref esp32_jtag_interface_esp32 "ESP32"
- \ref esp32_jtag_interface_esp32c3 "ESP32-C3"
- \ref esp32_jtag_interface_esp32s2 "ESP32-S2"
- \ref esp32_jtag_interface_esp32s3 "ESP32-S3"
This JTAG interface can be used with OpenOCD and GDB for On-Chip debugging
@ -1911,6 +1961,7 @@ that can be used without additional chips. For details, see:
- \ref esp32_jtag_interface_esp32 "ESP32"
- \ref esp32_jtag_interface_esp32c3 "ESP32-C3"
- \ref esp32_jtag_interface_esp32s2 "ESP32-S2"
- \ref esp32_jtag_interface_esp32s3 "ESP32-S3"
To use the JTAG debugging, the precompiled version of OpenOCD for ESP32 has to
@ -1952,7 +2003,8 @@ Detailed information on how to configure the JTAG interface of the respective
ESP32x SoC variant (family) can be found in ESP-IDF Programming Guide:
- [ESP32](https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-guides/jtag-debugging/index.html)
- [ESP32-C3](https://docs.espressif.com/projects/esp-idf/en/latest/esp32c3/api-guides/jtag-debugging/index.html)
- [ESP32-S3](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/api-guides/jtag-debugging/index.html)
- [ESP32-S2](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/api-guides/jtag-debugging/index.html)
- [ESP32-S3](https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/api-guides/jtag-debugging/index.html)
[Back to table of contents](#esp32_toc)

332
cpu/esp32/doc_esp32s2.txt Normal file
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@ -0,0 +1,332 @@
/*
* Copyright (C) 2022 Gunar Schorcht
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
@defgroup cpu_esp32_esp32s2 ESP32-S2 family
@ingroup cpu_esp32
@brief Specific properties of ESP32-S2 variant (family)
@author Gunar Schorcht <gunar@schorcht.net>
\section esp32_riot_esp32s2 Specific properties of ESP32-S2 variant (family)
## Embedded Flash and SPI RAM {#esp32_embedded_flash_ram_esp32s2}
There are many different versions of the ESP32-S2 chip and ESP32-S2 modules
used on ESP32-S2 boards. They differ in the size of embedded Flash and SPI RAM
as well as used SPI mode for Flash and SPI RAM.
These differences allow dozens of different versions of a board. For example,
there are 8 versions of the ESP32-S2 DevKitC-1 board with different flash
and SPI RAM sizes.
<center>
| Chip | Flash (Mode) | SPI RAM (Mode)
|:--------------|:---------------:|:--------------
| ESP32-S2 | - | -
| ESP32-S2FH2 | 2 MB (Quad SPI) | -
| ESP32-S2FH4 | 4 MB (Quad SPI) | -
| ESP32-S2FN4R2 | 4 MB (Quad SPI) | 2 MB (Quad SPI)
| ESP32-S2R2 | - | 2 MB (Quad SPI)
</center>
<br>
<center>
| Module | Chip | Flash (Mode) | SPI RAM (Mode)
|:-------------------------|:--------------|:-----------------:|:--------------
| ESP32-S2-MINI-1x-H4 | ESP32-S2FH4 | 4 MB (Quad SPI) | -
| ESP32-S2-MINI-1x-N4 | ESP32-S2FH4 | 4 MB (Quad SPI) | -
| ESP32-S2-MINI-1x-N4R2 | ESP32-S2N4R2 | 4 MB (Quad SPI) | 2 MB (Quad SPI)
| ESP32-S2-SOLO-H4 | ESP32-S2 | 4 MB (Quad SPI) | -
| ESP32-S2-SOLO-N4 | ESP32-S2 | 4 MB (Quad SPI) | -
| ESP32-S2-SOLO-N4R2 | ESP32-S2R2 | 4 MB (Quad SPI) | 2 MB (Quad SPI)
| ESP32-S2-WROOM | ESP32-S2 | 4 MB (Quad SPI) | -
| ESP32-S2-WROVER | ESP32-S2 | 4 MB (Quad SPI) | 2 MB (Quad SPI)
</center>
<b>x</b> Stands for the module versions with and without U (external antenna connector).
<br>
Depending on the chip or module used, it has to be specified as a feature in
the board definition whether SPI RAM is available (feature \ref esp32_spi_ram
"esp_spi_ram").
If the feature `esp_spi_ram` is given, the SPI RAM can be used as heap by
using the pseudo module `esp_spi_ram`.
If **Quad SPI mode** is used, **GPIO26 ... GPIO32** are occupied and cannot be
used for other purposes. In case of **Octal SPI mode**, the pseudomodule
`esp_spi_oct` is additionally enabled and **GPIO33 ... GPIO37** are occupied
if the SPI RAM is enabled by using the pseudomodule `esp_spi_ram`.
GPIO33 ... GPIO37 are then not available for other purposes.
Conflicts may occur when using these GPIOs.
## GPIO pins {#esp32_gpio_pins_esp32s2}
ESP32-S2 has 45 GPIO pins, where a subset can be used as ADC channel and as
low-power digital input/output in deep-sleep mode, the so-called RTC GPIOs.
Some of them are used by special SoC components and are not broken out on
all ESP32-S2 modules. The following table gives a short overview.
<center>
Pin | Type | ADC | RTC | PU / PD | Special function | Remarks
-------|:-------|:---:|:----:|:-------:|------------------|--------
GPIO0 | In/Out | - | X | X | - | Bootstrapping
GPIO1 | In/Out | X | X | X | - | -
GPIO2 | In/Out | X | X | X | - | -
GPIO3 | In/Out | X | X | X | - | Bootstrapping
GPIO4 | In/Out | X | X | X | - | -
GPIO5 | In/Out | X | X | X | - | -
GPIO6 | In/Out | X | X | X | - | -
GPIO7 | In/Out | X | X | X | - | -
GPIO8 | In/Out | X | X | X | - | -
GPIO9 | In/Out | X | X | X | - | -
GPIO10 | In/Out | X | X | X | - | -
GPIO11 | In/Out | X | X | X | - | -
GPIO12 | In/Out | X | X | X | - | -
GPIO13 | In/Out | X | X | X | - | -
GPIO14 | In/Out | X | X | X | - | -
GPIO15 | In/Out | X | X | X | XTAL_32K_P | External 32k crystal
GPIO16 | In/Out | X | X | X | XTAL_32K_N | External 32k crystal
GPIO17 | In/Out | X | X | X | - | -
GPIO18 | In/Out | X | X | X | - | -
GPIO19 | In/Out | X | X | X | USB D- | USB 2.0 OTG / USB-JTAG bridge
GPIO20 | In/Out | X | X | X | USB D+ | USB 2.0 OTG / USB-JTAG bridge
GPIO21 | In/Out | - | X | X | - | -
GPIO26 | In/Out | - | - | X | Flash/PSRAM SPICS1 | not available if SPI RAM is used
GPIO27 | In/Out | - | - | X | Flash/PSRAM SPIHD | not available
GPIO28 | In/Out | - | - | X | Flash/PSRAM SPIWP | not available
GPIO29 | In/Out | - | - | X | Flash/PSRAM SPICS0 | not available
GPIO30 | In/Out | - | - | X | Flash/PSRAM SPICLK | not available
GPIO31 | In/Out | - | - | X | Flash/PSRAM SPIQ | not available
GPIO32 | In/Out | - | - | X | Flash/PSRAM SPID | not available
GPIO33 | In/Out | - | - | X | Flash/PSRAM SPIQ4 | not available if octal Flash or SPI RAM is used
GPIO34 | In/Out | - | - | X | Flash/PSRAM SPIQ5 | not available if octal Flash or SPI RAM is used
GPIO35 | In/Out | - | - | X | Flash/PSRAM SPIQ6 | not available if octal Flash or SPI RAM is used
GPIO36 | In/Out | - | - | X | Flash/PSRAM SPIQ7 | not available if octal Flash or SPI RAM is used
GPIO37 | In/Out | - | - | X | Flash/PSRAM SPIQ8 | not available if octal Flash or SPI RAM is used
GPIO38 | In/Out | - | - | X | Flash/PSRAM SPIDQS | not available if octal Flash or SPI RAM is used
GPIO39 | In/Out | - | - | X | MTCK | JTAG interface
GPIO40 | In/Out | - | - | X | MTDO | JTAG interface
GPIO41 | In/Out | - | - | X | MTDI | JTAG interface
GPIO42 | In/Out | - | - | X | MTMS | JTAG interface
GPIO43 | In/Out | - | - | X | UART0 TX | Console
GPIO44 | In/Out | - | - | X | UART0 RX | Console
GPIO45 | In/Out | - | - | X | - | Bootstrapping (0 - 3.3V, 1 - 1.8V)
GPIO46 | In/Out | - | - | X | - | Bootstrapping
GPIO47 | In/Out | - | - | X | SPICLK_P | -
GPIO48 | In/Out | - | - | X | SPICLK_N | -
</center>
<b>PSRAM</b> - Stands for pseudo-static RAM and refers to the SPI RAM.
<br>
<b>ADC:</b> Pins that can be used as ADC channels.<br>
<b>RTC:</b> Pins that are RTC GPIOs and can be used in deep-sleep mode.<br>
<b>PU/PD:</b> Pins that have software configurable pull-up/pull-down functionality.<br>
GPIO0, GPIO3, GPIO45 and GPIO46 are bootstrapping. GPIO0 and GPIO46 pins are
used to boot ESP32-S2 in different modes:
<center>
GPIO0 | GPIO46 | Mode
:----:|:------:|----------
1 | X | SPI Boot mode to boot the firmware from flash (default mode)
0 | 1 | Download Boot mode for flashing the firmware
</center><br>
If `EFUSE_STRAP_JTAG_SEL` is set, GPIO3 is used to select the interface that
is used as JTAG interface.
<center>
GPIO3 | Mode
:----:|------------------------
1 | USB-JTAG bridge at GPIO19 and GPIO20 is used as JTAG interface
0 | GPIO39 to GPIO42 are used as JTAG interface
</center><br>
@note `If EFUSE_DIS_USB_JTAG` or `EFUSE_DIS_PAD_JTAG` are set, the interface
selection is fixed and GPIO3 is not used as bootstrapping pin.
GPIO45 is used to select the voltage `VDD_SPI` for the Flash/PSRAM interfaces
SPI0 and SPI1.
## ADC Channels {#esp32_adc_channels_esp32s2}
ESP32-S2 integrates two 12-bit ADCs (ADC1 and ADC2) with 20 channels in
total:
- **ADC1** supports 10 channels: GPIO1 ... GPIO10
- **ADC2** supports 10 channels: GPIO11 ... GPIO20
@note
- ADC2 is also used by the WiFi module. The GPIOs connected to ADC2 are
therefore not available as ADC channels if the modules `esp_wifi` or
`esp_now` are used.
- Vref can be read with function #adc_line_vref_to_gpio at any ADC2 channel,
that is at GPIO11 ... GPIO20.
- GPIO3 is a strapping pin und shouldn't be used as ADC channel
## I2C Interfaces {#esp32_i2c_interfaces_esp32s2}
ESP32-S2 has two built-in I2C interfaces.
The following table shows the default configuration of I2C interfaces
used for ESP32-S2 boards. It can be overridden by
[application-specific configurations](#esp32_application_specific_configurations).
<center>
Device | Signal | Pin | Symbol | Remarks
:----------|:-------|:-------|:--------------|:----------------
I2C_DEV(0) | | | `#I2C0_SPEED` | default is `I2C_SPEED_FAST`
I2C_DEV(0) | SCL | GPIO9 | `#I2C0_SCL` | -
I2C_DEV(0) | SDA | GPIO8 | `#I2C0_SDA` | -
</center><br>
## PWM Channels {#esp32_pwm_channels_esp32s2}
The ESP32-S2 LEDC module has 1 channel group with 8 channels. Each of
these channels can be clocked by one of the 4 timers.
## SPI Interfaces {#esp32_spi_interfaces_esp32s2}
ESP32-S2 has four SPI controllers where SPI0 and SPI1 share the same bus
and can only operate in memory mode while SPI2 and SPI3 can be used as general
purpose SPI:
- controller SPI0 is reserved for external memories like Flash and PSRAM
- controller SPI1 is reserved for external memories like Flash and PSRAM
- controller SPI2 can be used for peripherals (also called FSPI)
- controller SPI3 can be used for peripherals
Thus, SPI2 (`FSPI`) and SPI3 can be used as general purpose SPI in
RIOT as SPI_DEV(0) and SPI_DEV(1) by defining the symbols `SPI0_*`
and `SPI1_*`.
The following table shows the pin configuration used by default, even
though it **can vary** from board to board.
<center>
Device | Signal | Pin | Symbol | Remarks
:-----------------------|:------:|:-------|:-----------:|:---------------------------
`SPI_HOST0`/`SPI_HOST1` | SPICS0 | GPIO29 | - | reserved for flash and PSRAM
`SPI_HOST0`/`SPI_HOST1` | SPICS1 | GPIO26 | - | reserved for flash and PSRAM
`SPI_HOST0`/`SPI_HOST1` | SPICLK | GPIO30 | - | reserved for flash and PSRAM
`SPI_HOST0`/`SPI_HOST1` | SPID | GPIO32 | - | reserved for flash and PSRAM
`SPI_HOST0`/`SPI_HOST1` | SPIQ | GPIO31 | - | reserved for flash and PSRAM
`SPI_HOST0`/`SPI_HOST1` | SPIHD | GPIO27 | - | reserved for flash and PSRAM (only in `qio` or `qout` mode)
`SPI_HOST0`/`SPI_HOST1` | SPIWP | GPIO28 | - | reserved for flash and PSRAM (only in `qio` or `qout` mode)
`SPI_HOST0`/`SPI_HOST1` | SPIIO4 | GPIO33 | - | reserved for Flash and PSRAM (only in octal mode)
`SPI_HOST0`/`SPI_HOST1` | SPIIO5 | GPIO34 | - | reserved for Flash and PSRAM (only in octal mode)
`SPI_HOST0`/`SPI_HOST1` | SPIIO6 | GPIO35 | - | reserved for Flash and PSRAM (only in octal mode)
`SPI_HOST0`/`SPI_HOST1` | SPIIO7 | GPIO36 | - | reserved for Flash and PSRAM (only in octal mode)
`SPI_HOST0`/`SPI_HOST1` | SPIDQA | GPIO37 | - | reserved for Flash and PSRAM (only in octal mode)
`SPI_HOST2` (`FSPI`) | SCK | GPIO12 |`#SPI0_SCK` | can be used
`SPI_HOST2` (`FSPI`) | MOSI | GPIO11 |`#SPI0_MOSI` | can be used
`SPI_HOST2` (`FSPI`) | MISO | GPIO13 |`#SPI0_MISO` | can be used
`SPI_HOST2` (`FSPI`) | CS0 | GPIO10 |`#SPI0_CS0` | can be used
</center><br>
## Timers {#esp32_timers_esp32s2}
ESP32-S2 has two timer groups with two timers each, resulting in a total of
four timers. Since one timer is used as system timer, up to three timers
with one channel each can be used in RIOT as timer devices
TIMER_DEV(0) ... TIMER_DEV(2).
Additionally ESP32-S2 has three CCOMPARE registers which can be used
alternatively as timer devices TIMER_DEV(0) ... TIMER_DEV(2) can be used
in RIOT if the module `esp_hw_counter` is enabled.
## UART Interfaces {#esp32_uart_interfaces_esp32s2}
ESP32 integrates three UART interfaces. The following default pin
configuration of UART interfaces as used by a most boards can be overridden
by the application, see section [Application-Specific Configurations]
(#esp32_application_specific_configurations).
<center>
Device |Signal|Pin |Symbol |Remarks
:-----------|:-----|:-------|:-----------|:----------------
UART_DEV(0) | TxD | GPIO43 |`#UART0_TXD`| cannot be changed
UART_DEV(0) | RxD | GPIO44 |`#UART0_RXD`| cannot be changed
UART_DEV(1) | TxD | GPIO17 |`#UART1_TXD`| optional, can be overridden
UART_DEV(1) | RxD | GPIO18 |`#UART1_RXD`| optional, can be overridden
UART_DEV(2) | TxD | - |`UART2_TXD` | optional, can be overridden
UART_DEV(2) | RxD | - |`UART2_RXD` | optional, can be overridden
</center><br>
## JTAG Interface {#esp32_jtag_interface_esp32s2}
There are two options on how to use the JTAG interface on ESP32-S2:
1. Using the built-in USB-to-JTAG bridge connected to an USB cable as follows:
USB Signal | ESP32-S2 Pin
:--------------|:-----------
D- (white) | GPIO19
D+ (green) | GPIO20
V_Bus (red) | 5V
Ground (black) | GND
<br>
@note This option requires that the USB D- and USB D+ signals are connected
to the ESP32-S2 USB interface at GPIO19 and GPIO20.
2. Using an external JTAG adapter connected to the JTAG interface exposed
to GPIOs as follows:
JTAG Signal | ESP32S2 Pin
:-----------|:-----------
TRST_N | CHIP_PU
TDO | GPIO40 (MTDO)
TDI | GPIO41 (MTDI)
TCK | GPIO39 (MTCK)
TMS | GPIO42 (MTMS)
GND | GND
Using the built-in USB-to-JTAG is the default option, i.e. the JTAG interface
of the ESP32-S2 is connected to the built-in USB-to-JTAG bridge. To use an
external JTAG adapter, the JTAG interface of the ESP32-S2 has to be connected
to the GPIOs as shown above. For this purpose eFuses have to be burned with
the following command:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
espefuse.py burn_efuse JTAG_SEL_ENABLE --port /dev/ttyUSB0
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Once the eFuses are burned with this command and option `JTAG_SEL_ENABLE`,
GPIO3 is used as a bootstrapping pin to choose between the two options.
If GPIO3 is HIGH when ESP32-S2 is reset, the JTAG interface is connected
to the built-in USB to JTAG bridge and the USB cable can be used for on-chip
debugging. Otherwise, the JTAG interface is exposed to GPIO39 ... GPIO42
and an external JTAG adapter has to be used.
Alternatively, the integrated USB-to-JTAG bridge can be permanently disabled
with the following command:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
espefuse.py burn_efuse DIS_USB_JTAG --port /dev/ttyUSB0
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Once the eFuses are burned with this command and option `DIS_USB_JTAG`,
the JTAG interface is always exposed to GPIO4 ... GPIO7 and an external
JTAG adapter has to be used.
@note Burning eFuses is an irreversible operation.
For more information about JTAG configuration for ESP32-S2, refer to the
section [Configure Other JTAG Interface]
(https://docs.espressif.com/projects/esp-idf/en/latest/esp32s2/api-guides/jtag-debugging/configure-other-jtag.html)
in the ESP-IDF documentation.
*/