Re: 1-wire to USB converter that can use 1820s directly

[nobody@xxxxxxxxxxxx (Dave Houston)]

"Rod Speed" <rod.speed.aaa@xxxxxxxxx> wrote:

>Dave Houston <nobody@xxxxxxxxxxxx> wrote
>
>> The Elektor schematic I found shows it to be self-powered.
>> Is that correct?
>
>Powered from the USB, yes.

I misinterpreted the schematic, thinking the +5V balloon at the top
indicated an external supply. On a closer look, I see it's just a label.

http://www.bairesrobotics.com.ar/elektor/06-2002%20USB%20Interface%20for%20the%20I-Wire%20Bus.pdf

>> It appears to use the same Maxim drivers linked
>> in the DS9490R datasheet. Is this an HID driver?
>
>Not clear to me what a HID driver is. It definitely uses java.

Right after posting that I had an "Aha!" moment, realizing that if it were
an HID device, it would not need external drivers.

>> Why don't you like serial for this?
>
>Basically because I dont have enough serial ports available,
>the only one available is used for the X10 controller,
>and USB/serial converters are too much of a kludge.

If you have a free PCI slot, it's easy and relatively inexpensive to add
oodles of serial ports. I have an 8-port ByteRunner card in one PC and a
4-port card in another.

If I were to design something to do 1-wire, I'd use a PIC to handle the
1-wire network with a $5 Silicon Labs CP2102 USB-serial chip on the PIC end.
It communicates over the USB bus but is seen as a virtual serial port on the
PC end. It's much slower than USB but fast enough for this type of data
acquisition.