QUERY · ISSUE

ports/esp32：a bug with Hardware SPI Initialize on ESP32-S3

openby EngineerWillopened 2022-12-16updated 2022-12-17

bugport-esp32

Hi,all:

Problem description and analysis

Hardware: ESP32S3
Firmware version: esp32/GENERIC_S3 v1.19.1 (2022-06-18) or master branch
Abstract: SPI(1) and SPI(2) need two initializations to work perfectly in each operation. If two initializations of different Baudrates are not carried out, SPI may not work.

code and pictures

Initialize with different baudrates()

self.spi = SPI(2,baudrate=4_000_000,polarity=0, phase=0,sck=Pin(SCK,Pin.OUT),mosi=Pin(MOSI,Pin.OUT))
self.spi = SPI(2,baudrate=8_000_000,polarity=0, phase=0,sck=Pin(SCK,Pin.OUT),mosi=Pin(MOSI,Pin.OUT))

Initialize with same baudrates(In order to reproduce the problem 100%, you also can initialize it once and run it again)

self.spi = SPI(2,baudrate=8_000_000,polarity=0, phase=0,sck=Pin(SCK,Pin.OUT),mosi=Pin(MOSI,Pin.OUT))
self.spi = SPI(2,baudrate=8_000_000,polarity=0, phase=0,sck=Pin(SCK,Pin.OUT),mosi=Pin(MOSI,Pin.OUT))

details

First time

I used the firmware V1.91.1 and found that SPI (1) initialization was abnormal. SPI(2) can work normally.
However, when I tried for the second time (after stop), I found that it could not work.
I tried to restart it and it could work again, but it still couldn't work the second time.
Then I tried various methods and accidentally found that baudrate could work after modification. So I conducted two initializations,The baudrate needs of the first initialization were different from that of the second initialization,The program could run perfectly, no matter whether it was STOP or not.

self.spi = SPI(2,baudrate=4_000_000,polarity=0, phase=0,sck=Pin(SCK,Pin.OUT),mosi=Pin(MOSI,Pin.OUT))
self.spi = SPI(2,baudrate=8_000_000,polarity=0, phase=0,sck=Pin(SCK,Pin.OUT),mosi=Pin(MOSI,Pin.OUT))

I found out that lssues #8634 suffers from a similar problem and saw the initialization issue solved in #9498

The second time

I tried to use the master branch to build a new firmware to try,
and then I found that SPI(1) and SPI(2) can be initialized normally and work, but the problem still exists that the initialization needs to be twice.

CANDIDATE · ISSUE

Possible bug with Hardware SPI(1) on ESP32-S3

closedby beyonloopened 2022-05-05updated 2025-04-24

port-esp32

Hi all.

I'm using the ESP32-S3-WROOM-1 (N8R2 - 8MB Flash and 2 MB RAM), specifically this kit: ESP32-S3-DEVKITC-1-N8R2

The hardware SPI is working just on the SPI(2). The SPI(1) do not works.

As I know, the ESP32-S3, like as the ESP32 has two free Hardware SPI to use (SPI 1 and SPI 2). It has 4 in total, but two SPI (SPI 3 and SPI 4) are used by the RAM/FLASH. So, should works Hardware SPI number 1 and number 2, right?

Follow the tests with the ESP32-S3:

>>> import os
>>> os.uname()
(sysname='esp32', nodename='esp32', release='1.18.0', version='v1.18 on 2022-05-05', machine='ESP32S3 module (spiram) with ESP32S3')
>>> 
>>> from machine import SPI, Pin
>>> 
>>> spi  = SPI(1, baudrate=5_000_000, phase=1, sck=Pin(15), mosi=Pin(16), miso=Pin(17))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
OSError: invalid configuration
>>> 
>>> spi  = SPI(2, baudrate=5_000_000, phase=1, sck=Pin(15), mosi=Pin(16), miso=Pin(17))
>>> 
>>> spi  = SPI(3, baudrate=5_000_000, phase=1, sck=Pin(15), mosi=Pin(16), miso=Pin(17))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: SPI(3) doesn't exist
>>> 
>>> spi  = SPI(4, baudrate=5_000_000, phase=1, sck=Pin(15), mosi=Pin(16), miso=Pin(17))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: SPI(4) doesn't exist
>>>

Follow below the same test with the ESP32:

>>> import os
>>> os.uname()
(sysname='esp32', nodename='esp32', release='1.18.0', version='v1.18 on 2022-01-17', machine='ESP32 module with ESP32')
>>> 
>>> from machine import SPI, Pin
>>> spi  = SPI(1, baudrate=5_000_000, phase=1, sck=Pin(15), mosi=Pin(16), miso=Pin(17))
>>> 
>>> spi  = SPI(2, baudrate=5_000_000, phase=1, sck=Pin(15), mosi=Pin(16), miso=Pin(17))
>>> 
>>> spi  = SPI(3, baudrate=5_000_000, phase=1, sck=Pin(15), mosi=Pin(16), miso=Pin(17))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: SPI(3) doesn't exist
>>> spi  = SPI(4, baudrate=5_000_000, phase=1, sck=Pin(15), mosi=Pin(16), miso=Pin(17))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: SPI(4) doesn't exist
>>>

I missed some configuration or is really a BUG?

Thank you.