Re: Ability to drive multiple IR transmitters independantly from PC

[nobody@xxxxxxxxxxxx (Dave Houston)]

"Bill Kearney" <wkearney99@xxxxxxxxxxx> wrote:
>
>Assuming you make use of single port devices all from the same vendor and
>the then the same model/production run.  While a number of them do base
>themselves on the same chipsets not all make use of the same driver
>software, and some are worse than others.  Then there's the USB bandwidth
>and power issues.  There you're running up against how well (or poorly) the
>hardware and drivers for the USB ports are set up.

BULL!

Under Windows...

ALL FTDI chipsets work with the same drivers. (They offer both VCP and a
direct interface with an API - the device developer chooses which.) ALL
SiliconLabs chips work with the same driver. I haven't tried anything with
the Prolific chipset but the fact they offer only one driver speaks to the
fact that they must all work with that one driver.

I have used multi-port hubs. If you search, you will find I was the first to
post about them here several years ago. The Entrega (later Xircom, later
Intel) 4U2S1P hub was one of the earliest. There's absolutely no difference
in operation between the serial ports on such hubs and multiple single port
adapters from the same manufacturer which is exactly what I recommended,
even giving a URL to the specific adapter.

I have an adapter made by FTDI using their very first chipset. (I think I
was the first to post here about them.) It works with the same driver as any
using their latest chips as well as any in between. I have 3 different
SiliconLabs chips (CP2101, CP2102, CP2103). All use the same driver.

I have had an FTDI based adapter, 2 SiliconLabs based adapters, the Entrega
hub with two USB-serial ports, a USB-UIRT (uses a later FTDI chipset) and a
Byterunner 8-port PCI card on the same PC along with two motherboard serial
ports with absolutely none of the fictional driver "nightmares" you predict.
Windows finds the new hardware, asks for a disk if it doesn't already have a
driver, installs the driver once (if needed) and operation is transparent
and uneventful thereafter.

I have reassigned port names to test that my software can enumerate and
connect to COM1-COM99.

I believe the FTDI and SiliconLabs drivers have been added to the Linux
kernel. The FTDI drivers are included in XP.

Macs never had true serial ports and some of the USB-serial adapters
originally designed for that market are the ones most often complained about
by folks who try using them with PCs and applications that need all of the
handshaking lines.


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