File Transfer

It is necessary for us to be able to have a control on the data that is being shared via UART.

File protocols allow us to create a custom packet of data that contains certain info abt the actual data, thus providing a control over it.

Some protocols

:

🔸 1. XMODEM

The simplest protocol.

• Developed by Ward Christensen in 1977.
• Sends data in 128-byte chunks.
• Uses checksum or CRC for error detection.
• Waits for ACK (acknowledge) or NAK (negative acknowledge) after each block.
• No support for:
  • File name
  • File size
  • Resuming interrupted transfers

Structure of a block:

✅ Simple and reliable

❌ Slow, no metadata