Description:

This Raspberry Pi Hat was designed for those who need a flexible serial UART connection with another device.  The male DB9 connector provides a full RS232 hardware interface just like older PCs used to.

The jumpers allow various configurations without changing any other hardware.  

• Loopback (TX and RX connected together, so what is sent is automatically received)
• Null Modem (TX and RX swapped on the board. Useful for straight-through cables)
• Straight Through (This is useful when you have a null-modem cable)
• Handshaking
  • CTS and RTS can be configured as straight through, or they can be swapped.
  • Cable DCD, DTR,DSR, and RI can be connected in any configuration

The hat comes with 11mm M2.5 standoffs, screws, and nuts.  Serial cables are available separately.