FTDI Community

Please login or register.

Login with username, password and session length.
Advanced Search  

News:

Welcome to the FTDI Community!

Please read our Welcome Note

Technical Support enquires
please contact the team
@ FTDI Support


New Bridgetek Community is now open

Please note that we have created the Bridgetek Community to discuss all Bridgetek products e.g. EVE, MCU.

Please follow this link and create a new user account to get started.

Bridgetek Community

Author Topic: Questions on ft4232h to rs485  (Read 9919 times)

ivanooi

  • Newbie
  • *
  • Posts: 1
    • View Profile
Questions on ft4232h to rs485
« on: December 12, 2020, 03:09:04 AM »

Hi all ,

I am using ft4232 as converter to rs485 and I have some questions :

1) can I configure the txden = ri enable without the need for an eeprom ?
2) I have the usb to rs485 plus four evaluation module and wondering do you have the schematic for that board?
3) why for rs485 module local echo is enabled?

Thanks
Logged

FTDI Community

  • Administrator
  • Hero Member
  • *****
  • Posts: 896
    • View Profile
Re: Questions on ft4232h to rs485
« Reply #1 on: December 15, 2020, 04:40:56 PM »

Hello,

In order to configure TXDEN, an external EEPROM is required:

* RI#/ or TXDEN is selectable in the EEPROM. Default is RI#.

I can provide the USB-COM485-PLUS4 if you contact us via email:

https://www.ftdichip.com/FTContact.htm

RS485 systems often have local echo enabled. This means any data transmitted by a device is echoed back to itself.

There is a hardware option to disable local echo on the USB-COM485-PLUS4. Please refer to the USB-COM485-PLUS4 Datasheet.
Connect pin7 and pin 8 can disable the local echo function. The local echo is enabled by default.

Best Regards,
FTDI Community
Logged