[Lazarus] libusb access from Lazarus

[Mark Morgan Lloyd]

Luca Olivetti wrote:
> En/na Mark Morgan Lloyd ha escrit:
> 
>> Thanks Henry, got that. One of the things I'm due to be asked about is 
>> recoding some RS232 monitoring stuff, and I was wondering whether there 
>> was any magic I was missing.
> 
> You shouldn't need libusb for that, the usb<->serial converter should 
> work right out of the box (most of them do nowadays) but instead of 
> using /dev/ttyS* it will (most probably depending on udev rules) be 
> assigned to /dev/ttyUSB*.
> I use synaser (http://www.ararat.cz/synapse) to program serial 
> communications in a cross platform (at least win/linux) way.

I agree that access to the ports shouldn't need anything other than 
/dev/ttyUSBx, but in the case of monitoring there's a need to get 
accurate timestamps on every character and signal transition which 
complicates things. As a result any possibility of improved resolution 
is worth pursuing.

Incidentally, I can't remember whether it was this list or FPC where 
there have been questions about accessing USB serial ports from DOS 
programs. I've run DOS code inside DOSemu on Linux driving USB serial 
ports for weeks without error, although obviously the longer-term plan 
is to convert it to run without an emulation layer.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

[Opinions above are the author's, not those of his employers or colleagues]