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usb_device.c: Fix EP buffer size limitation for isochronous endpoints#78

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maximus64 wants to merge 1 commit intoraspberrypi:masterfrom
maximus64:fix_usb_max_size
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usb_device.c: Fix EP buffer size limitation for isochronous endpoints#78
maximus64 wants to merge 1 commit intoraspberrypi:masterfrom
maximus64:fix_usb_max_size

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The buffer size for USB endpoints was previously limited by the endpoints buffer stride, which is 128 bytes * 2 for isochronous endpoints and 64 bytes for bulk transfers.

According to the USB full-speed specification, the maximum frame size can go up to 1023 bytes. The RP2040 microcontroller has 4KB of DPSRAM, which can support this maximum frame size.

This commit removes the 128 bytes * 2 limitation for isochronous endpoints, allowing support for the full 1023-byte frame size.

The buffer size for USB endpoints was previously limited by the
endpoints buffer stride, which is 128 bytes * 2 for isochronous
endpoints and 64 bytes for bulk transfers.

According to the USB full-speed specification, the maximum frame size
can go up to 1023 bytes. The RP2040 microcontroller has 4KB of DPSRAM,
which can support this maximum frame size.

This commit removes the 128 bytes * 2 limitation for isochronous
endpoints, allowing support for the full 1023-byte frame size.

Signed-off-by: Khoa Hoang <admin@khoahoang.com>
sctanf added a commit to sctanf/picoamp that referenced this pull request Aug 22, 2024
@kilograham kilograham requested review from liamfraser and removed request for liamfraser November 19, 2024 21:19
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