This is a short scratchbook for some notes concerning the homemade CAT cable for Yaesu FT-817 / 818 radios. It uses TTL level on the serial interfaces. Thus you can simpy use USB-serial chips like FT-232 or PL2303 directly. For reference here is my pinout for the PL2303 chip:
Pin Pin
pl2303 FT-817
1 TXD ---- RX D
5 RXD ---- TX D
7 GND ---- GND
3 RTS -+
| Short hardware handshake
11 CTS -+
2 DTR -+
|
9 DSR -+ Short hardware handshake
|
10 DCD -+The shorts for RTS/CTS and DTR/DSR/DCD are not needed if the software is set to no hardware handshake.
Update
For a recent homebrew cable I used the FT232 version of the USB serial cable. Interestingly the pinout of the SSOP package is exactly the same (for the required pins here):
Pin Pin
FT232 FT-817
1 TXD ---- RX D
5 RXD ---- TX D
7 GND ---- GND
3 RTS
11 CTS
2 DTR
9 DSR
10 DCDSee following quick and dirty KiCad schematic:
A sample was made from a FT232 USB serial adapter that is usually available as programmer interface for Arduino etc.
Please be aware that this may eventually break your rig. Use at your own risk. I am not liable in any way for damage to your equipment.