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doc: update s3 psram vaddr max range size

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Armando 2023-05-17 12:43:50 +08:00 committed by Armando (Dou Yiwen)
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commit 0b1f773517
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11
docs/en/api-guides/external-ram.rst
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@ -8,10 +8,13 @@ Support for External RAM
Introduction
============
{IDF_TARGET_PSRAM_SIZE:default="Value not updated", esp32="4 MB", esp32s2="10.5 MB", esp32s3="16 MB"}
{IDF_TARGET_PSRAM_VADDR_SIZE:default="Value not updated", esp32="4 MB", esp32s2="10.5 MB", esp32s3="32 MB"}
{IDF_TARGET_NAME} has a few hundred kilobytes of internal RAM, residing on the same die as the rest of the chip components. It can be insufficient for some purposes, so {IDF_TARGET_NAME} has the ability to also use up to {IDF_TARGET_PSRAM_SIZE} of external SPI RAM memory. The external memory is incorporated in the memory map and, with certain restrictions, is usable in the same way as internal data RAM.
{IDF_TARGET_NAME} has a few hundred kilobytes of internal RAM, residing on the same die as the rest of the chip components. It can be insufficient for some purposes, {IDF_TARGET_NAME} has the ability to use up to {IDF_TARGET_PSRAM_VADDR_SIZE} of virtual addresses for external SPI RAM memory. The external memory is incorporated in the memory map and, with certain restrictions, is usable in the same way as internal data RAM.
.. only:: esp32s3
The {IDF_TARGET_PSRAM_VADDR_SIZE} virtual addresses are shared with flash instructions and rodata.
Hardware
========
@ -24,7 +27,7 @@ Hardware
.. note::
Espressif produces both modules and system-in-package chips that integrate compatible PSRAM and flash and are ready to mount on a product PCB. Consult the Espressif website for more information.
Espressif produces both modules and system-in-package chips that integrate compatible PSRAM and flash and are ready to mount on a product PCB. Consult the Espressif website for more information. If you're using a custom PSRAM chip, ESP-IDF SDK might not be compatible with it.
For specific details about connecting the SoC or module pins to an external PSRAM chip, consult the SoC or module datasheet.
@ -58,7 +61,7 @@ Select this option by choosing "Integrate RAM into memory map" from :ref:`CONFIG
This is the most basic option for external SPI RAM integration. Most likely, you will need another, more advanced option.
During the ESP-IDF startup, external RAM is mapped into the data address space, starting at address {IDF_TARGET_PSRAM_ADDR_START} (byte-accessible). The length of this region is the same as the SPI RAM size (up to the limit of {IDF_TARGET_PSRAM_SIZE}).
During the ESP-IDF startup, external RAM is mapped into the data address space, starting at address {IDF_TARGET_PSRAM_ADDR_START} (byte-accessible). The length of this region is the same as the SPI RAM size (up to the limit of {IDF_TARGET_PSRAM_VADDR_SIZE}).
Applications can manually place data in external memory by creating pointers to this region. So if an application uses external memory, it is responsible for all management of the external SPI RAM: coordinating buffer usage, preventing corruption, etc.