OK, then you likely don't need a FT232 chip. The microcontroller, whichever one you use, will likely have USB2 built-in. Or just make sure it does, so many chips have this.
Most chips like the STM32 will have quite a lot of peripherals built-in. USB, UARTS and analog and counters, and "whatever". You almost never need external chips. On Wed, Dec 2, 2020 at 12:00 PM <ken.stra...@gmail.com> wrote: > To clarify: > I am working on an accessory for a Tormach mill running PathPilot (a > flavour > of LinuxCNC). It is for personal use so I don't need to especially worry > about product cost but obviously I'd rather not spend a lot on something > that may eventually be abandoned when I get a better idea. I could modify > the Tormach source code to solve my timing problems but I'd prefer to use > it > unchanged to ease the installation of their updates. > > Possible transmission speed increases with USB3 or even USB2 are irrelevant > since the maximum data rate will be less than 100 bytes/sec. > > -----Original Message----- > From: Chris Albertson <albertson.ch...@gmail.com> > Sent: December 2, 2020 12:41 PM > To: Enhanced Machine Controller (EMC) <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] USB - Serial question > > As said, you can simply have your device hold the ft232 reset pin low until > it needs to be high but if you look at the Arduino UNO the way they did > their USB/Serial interface design was to use an ATmega8U2 microcontroller. > Older Arduinos used the ft232 chip, then they switched to the ATmega8U2 > microcontroller because it offers better flexibility This chip has an > on-chip a USB2.0 interface. > > The trouble with holding the reset pin low is that you then need a > microcontroller to decide when to raise the pin. But if you do that, why > not use a microcontroller that can directly drive USB and not have to > install a ft232 chip. This is actually a really common design ad > maybe most engineers go this route. There is no need for the ft232 if your > microcontroller already has USB pins. > > One more thing, I don't know what you are building but if this is a new > product you might want to look at newer USB standards. > > On Tue, Dec 1, 2020 at 6:23 PM <ken.stra...@gmail.com> wrote: > > > I'm looking for a USB <-> Serial chip (something similar to the FT232R > > or > > CH340) that has an enable pin so it can be plugged into the computer's > > USB port but not initiate the connection process until the enable pin > > is activated. One possibility is to power up the widget, wait and then > > boot Linux but this is prone to operator error. Or perhaps someone can > > suggest an alternate approach. > > > > To explain: > > I am building an Arduino controlled widget that requires a lengthy > > initialization delay to home the axis and other tasks before it is > > ready to "talk" to Linux. I want to leave it plugged into the > > computer's USB port but unfortunately Linux boots before it completes > initialization. > > > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > -- > > Chris Albertson > Redondo Beach, California > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users