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Httpclient POST message size

Another question:
How can I send large (>2048 bytes) POST messages, using send(uint8_t sn, uint8_t * buf, uint16_t len) ?

Thank you.

Hello, tuxxas

Thank you for your interest in W7500.

Socket buffer default value is 2KB as you check. And we offer user the Sn_TXBUF_SIZE & Sn_RXBUF_SIZE registers to control the size.

Socket has limited memory, 32KB, and user can control the buffer size in the limit.

In W7500x_wztoe.h, there are setSn_TXBUF_SIZE and setSn_RXBUF_SIZE.

with them, you can modify the socket buffer size.

Thank you


TCP/IP is a byte stream protocol.

You can send as many bytes as you like. (no limit, once connection is established)
Just call send() more times, each time with your next part of the content.
For example: you can use it to read sectors from a SD card 512 bytes at a time and send files of many MegaBytes just by calling send() for each sector.

Best regards,
Edwin van den Oetelaar

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