You can write to the EEPROM via the FT4232 chip using the tool, ftdi_eeprom, contained within a later version of libftdi, libftdi1, version, 1.4. The following page from the CM3 home automation board (containing a PI and the FTDI 4232H chip), describes how to obtain and build the version of libftdi containing ftdi_eeprom which allows you to
write a configuration to the EEPROM, erase the EEPROM, and flash the EEPROM, not in that order. This appears to work ok on our BB-X15 (uname -r and /etc/dogtag provided below).
The only thing which seems a
little weird to me is, when I use the ftdi_eeprom utility to re-write the
EEPROM, the FTDI chip is restarted, and /dev/ttyUSB0..USB3 are disconnected,
and then re-connected. But for some reason, /dev/ttyUSB3 doesn't
re-connect until I re-boot the BB-X15.
OS Image versions:
uname -r: 4.4.110-ti-r142
cat /etc/dogtag: Debian Image (Console Image) 2018-01-01
cat /etc/debian_version: 8.10
Attached are photos of the BB-X15 connected to the FT4232H Mini Module and a photo of the scope shot of the TXDEN line and Txd line for /dev/ttyUSB3 channel with the chd_rs485 flag (channel's a..d) set to true in the EEPROM config file:
Let me know what else you'd like to know about this setup or have any suggestions/concerns.
Will try to update this as I get further along.