esp_tusb_init_console with blocking io support? (IEC-329)

[wuyuanyi135]

Is your feature request related to a problem?

Hi, all

esp_tusb_init_console currently provides a non-blocking IO (reading stdin returns immediately with an EOF). Now that the USB JTAG/CDC API also provide the blocking IO, is it possible to include the blocking variant in TinyUSB CDC as well?

Describe the solution you'd like.

esp_tusb_init_console can be set to blocking IO

Describe alternatives you've considered.

No response

Additional context.

No response

[github-actions]

Hi @wuyuanyi135! Please be aware that the following suggestions are generated by a bot and haven't been fact-checked by Espressif Systems. We hope that this message will help you until an Espressif Engineer looks at your issue.

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Thank you for your feature request and detailed explanation.

Based on the current Espressif documentation, the esp_tusb_init_console() function (used to redirect standard I/O streams to USB CDC-ACM via TinyUSB) does not provide an option to configure blocking or non-blocking I/O behavior directly. The documentation states that calling esp_tusb_init_console() switches standard input/output streams to USB, but it does not mention any configuration for blocking or non-blocking modes for TinyUSB CDC-ACM. The default behavior is that reading from stdin returns immediately with EOF if no data is available, which matches your observation USB Device Stack - ESP32-S3.

In contrast, for the USB Serial/JTAG and UART drivers, Espressif provides explicit APIs and configuration options to switch between blocking and non-blocking I/O modes, as described in the standard I/O and console output documentation for various chips Standard I/O and Console Output - ESP32-S3.

Summary:
Currently, there is no documented way to enable blocking I/O for esp_tusb_init_console() (TinyUSB CDC-ACM) in ESP-IDF. Your feature request to allow blocking I/O for this function is valid and not currently supported according to the available documentation.

If you require blocking I/O behavior, you may need to implement additional buffering or polling logic in your application, or consider using the USB Serial/JTAG or UART interfaces, which do support configurable blocking modes.

If you need further clarification or want to track this as a feature request, I recommend opening an issue on the official ESP-IDF repository or following up with Espressif support.

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References:

• USB Device Stack - ESP32-S3
• Standard I/O and Console Output - ESP32-S3