FT231X (instead of FT232R, FT93x)

RaymanRayman Posts: 9,816
edited 2019-11-01 - 22:42:44 in Propeller 2
Think I'm finally going to switch to FT231x for my P2 board.
Smaller and 1/2 the price although it does need two 27 ohm resistors that FT232R doesn't need.

But, looking at the P2-ES circuit diagram, looks like one needs to use FT_PROG utility to make the CBUS pins work as desired.
Does Parallax do this for every board they make?
Or, do they buy them preprogrammed?

BTW: I spent a lot of time seeing if FT93x could be used instead. Sadly, I don't think it is possible to make DTR work the same way.
It does have 4 com port interfaces though and one could be used to signal reset, but that's just a pain.
The other issue I found is that you can't make the UART automatically have the same baud as the virtual com port.
Would have been a lot of potential if not for these issues...
Prop Info and Apps: http://www.rayslogic.com/

Comments

  • jmgjmg Posts: 14,027
    Rayman wrote: »
    BTW: I spent a lot of time seeing if FT93x could be used instead. Sadly, I don't think it is possible to make DTR work the same way.
    It does have 4 com port interfaces though and one could be used to signal reset, but that's just a pain.
    The other issue I found is that you can't make the UART automatically have the same baud as the virtual com port.
    Would have been a lot of potential if not for these issues...

    When I looked at those, the fixed SysCLK was not high-baud friendly either...

    Rayman wrote: »
    Think I'm finally going to switch to FT231x for my P2 board.
    Smaller and 1/2 the price although it does need two 27 ohm resistors that FT232R doesn't need..

    You could look instead at the CP2102N, and EFM8UB3 as used in P2D2. They can be made pin compatible.
    I've got code for UB3 that does a 100uS reset monostable on DTR leading edge, and has large buffers (1536 bytes on Rx) intended for P2 use.
    It works with SiLabs drivers, and can set baud speeds up to 12MBd. (12M.8.n.2 and 8M.8.n.2 seem to test ok, half duplex, within buffer limits)



    I think your heading might have meant to say `FT231X (instead of FT232R, FT93x)` ?

  • Thanks, I fixed the heading.
    Right now, I'm tired of looking at alternatives, but might reconsider later...

    FTDI advertises their "Royalty Free VCP" drivers as an advantage.
    How does CP2102N handle this?
    Prop Info and Apps: http://www.rayslogic.com/
  • jmgjmg Posts: 14,027
    Rayman wrote: »
    FTDI advertises their "Royalty Free VCP" drivers as an advantage.
    How does CP2102N handle this?

    Much the same way: Silabs have VCP drivers, that work for both CP2102N, and EFM8UB3

    CP2102N is cheaper than FT231X, and EFM8UB3 is cheaper again, but needs code (It has a USB bootloader, for loading code)
  • FT231x features for USB power and battery charging management that set it apart for me. I don’t think the CP2102 has those. FT_PROG sets those options, the relevant CBUS signals, by applying an XML template through it‘s USB. It can be a normal part of board config, but I don’t know how Parallax handles it.
  • jmg wrote: »
    I've got code for UB3 that does a 100uS reset monostable on DTR leading edge, and has large buffers (1536 bytes on Rx) intended for P2 use.
    It works with SiLabs drivers, and can set baud speeds up to 12MBd. (12M.8.n.2 and 8M.8.n.2 seem to test ok, half duplex, within buffer limits)

    Is that UB3 source code available ?
  • FTDI just told me that the next version of the toolchain should fix my DTR and baud problem.
    So, I have to remember to check in with them sometime in the future...
    Prop Info and Apps: http://www.rayslogic.com/
  • Rayman,
    We do configure the FTDI settings on each board we make. We test most of our new products with Raspberry Pi's, running a script. When the script detects a new device, it checks the FTDI configuration, and if it is not configured, it loads the configuration, then cycles power to the USB ports. After verifying the configuration, it loads the test program, and performs any interactions needed to test the board.

    We set the CBUS pins to enable different current limits, based on whether the board is connected to a charger or a computer, and whether or not the computer has granted the board an extra allotment of current. We also change the manufacturer and product description strings.
Sign In or Register to comment.