Hello! DS2490, and I agree with you regarding the fob one that contains a cipher button. (Or the button that contains a time clock.) My local food store has buttons positioned all over it. They routinely go around with a special device to read them. When seeing that, they arrived about the same time as the self check machines, I described that I knew the devices, and was familiar with the concepts behind the readers. Naturally I got stared at.
Mine stopped working a while ago. I'll probably buy a new one soon. Now when I want to work with the technology I promptly select an FTDI based serial adapter and a DS9097 adapter that I originally obtained about the time the technology got started up in earnest. Or now that I have an RPI here, I'll probably assemble a DS2482 based adapter and work out the logic behind how to attach the widget to the system and make it work from that perspective. And as it happens that adapter was obtained about the time the whole project got started Paul along with its mate. ----- Gregg C Levine gregg.drw...@gmail.com "This signature fought the Time Wars, time and again." On Sun, Sep 29, 2013 at 12:05 PM, Jan Kandziora <j...@gmx.de> wrote: > Am 29.09.2013 11:22, schrieb Vajk Fekete: >> The key piece of information is, that ds9490 uses the ds2490 chip. Which is >> kinda discontinued by dallas/maxim. At a point they stated they have made a >> huge lot that will last years, and stopped production. They may have >> restarted production, or are just keeping price high enough to fulfill the >> prediction "stock will last for years" >> > The assembled DS9490 adapter is a lock-in component for nearly all PC > cash registers, which use iButtons as a security token and this adaptor > for connecting them. > > This is a small, simple cash-cow for Maxim, so I doubt it will ever > disappear. It is however hard to get the DS2490 chip from the usual > vendors to make own adaptors. You have to place an order >100 pieces to > get some. > > >> Your best bet is to get any clone that uses the ds2480 chip and some sort >> of usb serial port. As far as I know, the ds24080 is abou the same >> functionality as the ds2490, just missing the native usb interface. >> > They are quite different when scanning the bus for new chips. Both the > DS2480B and DS2940 have some acceleration function for making the > scanning faster and generating less interrupts. The DS2480B uses the > host's 16-Byte UART FIFO to scan for one onewire chip with one > interrupt, while the DS2490 (due to having more RAM and an own CPU) can > do that inpendendly of the host, relieving the CPU from the scanning > load even more. > > > Maybe it's time to make an own USB->Onewire adaptor with better search > acceleration than the FTDI+DS2480B types have. It could be based on a > cheap AVR µC and the Opensource V-USB firmware. > > > Kind regards > > Jan > > ------------------------------------------------------------------------------ > October Webinars: Code for Performance > Free Intel webinars can help you accelerate application performance. > Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from > the latest Intel processors and coprocessors. See abstracts and register > > http://pubads.g.doubleclick.net/gampad/clk?id=60133471&iu=/4140/ostg.clktrk > _______________________________________________ > Owfs-developers mailing list > Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers ------------------------------------------------------------------------------ October Webinars: Code for Performance Free Intel webinars can help you accelerate application performance. Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from the latest Intel processors and coprocessors. See abstracts and register > http://pubads.g.doubleclick.net/gampad/clk?id=60133471&iu=/4140/ostg.clktrk _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
