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sshfs can not connect to nslu2 running SlugOS 5.3

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  • teemu.nikkila
    Hi, I upgraded my NSLU2 to SlugOS 5.3 beta and now there is an issue with sshfs. I can connect to my Slug with ssh just fine, but when I try to mount a dir
    Message 1 of 16 , Mar 29 6:27 AM
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      Hi,

      I upgraded my NSLU2 to SlugOS 5.3 beta and now there is an issue with sshfs. I can connect to my Slug with ssh just fine, but when I try to mount a dir from it with sshfs I get:

      read: Connection reset by peer

      On the Slug I see in /var/log/messages:

      Mar 29 18:30:32 (none) auth.info sshd[5186]: subsystem request for sftp
      Mar 29 18:30:32 (none) auth.err sshd[5186]: error: subsystem: cannot stat /usr/libexec/sftp-server: No such file or directory

      What should I do to enable / install the sftp-server? Openssh (4.6p1-r6) is up to date.

      Cheers,
      Teemu
    • Harsh
      The primary installation of SlugOS5.3 is quite minimalistic. To hazard a guess, its probably missing this: openssh-sftp-server Try installing it using ipkg and
      Message 2 of 16 , Mar 29 7:06 AM
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        The primary installation of SlugOS5.3 is quite minimalistic. To hazard a guess, its probably missing this: openssh-sftp-server

        Try installing it using ipkg and see if it works?

        -H


        From: teemu.nikkila <teemu.nikkila@...>
        To: nslu2-linux@yahoogroups.com
        Sent: Mon, 29 March, 2010 9:27:50 PM
        Subject: [nslu2-linux] sshfs can not connect to nslu2 running SlugOS 5.3

         

        Hi,

        I upgraded my NSLU2 to SlugOS 5.3 beta and now there is an issue with sshfs. I can connect to my Slug with ssh just fine, but when I try to mount a dir from it with sshfs I get:

        read: Connection reset by peer

        On the Slug I see in /var/log/messages:

        Mar 29 18:30:32 (none) auth.info sshd[5186]: subsystem request for sftp
        Mar 29 18:30:32 (none) auth.err sshd[5186]: error: subsystem: cannot stat /usr/libexec/ sftp-server: No such file or directory

        What should I do to enable / install the sftp-server? Openssh (4.6p1-r6) is up to date.

        Cheers,
        Teemu



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      • teemu.nikkila
        ... It was, now it works, thanks!
        Message 3 of 16 , Mar 29 7:57 AM
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          > The primary installation of SlugOS5.3 is quite minimalistic. To hazard a guess, its probably missing this: openssh-sftp-server

          It was, now it works, thanks!
        • Emil Granström
          Hello. I am a newbie here using the slug. I will be using the slug for temp meassurements using OWFS in our cottage, I will generate graphs and alarms for
          Message 4 of 16 , Mar 29 11:38 AM
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            Hello. I am a newbie here using the slug.
            I will be using the slug for temp meassurements using OWFS in our
            cottage, I will generate graphs and alarms for critical temps.
            I will be runing the slug from a 4GB USB thumbdrive. To reduce the
            access of the disk I have done the "touch /.ext3flash" command.

            I assume this question is a bit hard to comment on but can anyone give
            me a hint on what to expect when it comes to the lifecycle of the USB
            drive ?
            If the slug is on 24-7 how long can it be before I can expect problems ?
            Are we talking week, months, years or what ?
            I hope someone with a bit more handson experience can comment or share
            some insights.

            Brg
            Emil, in Sweden.
          • Brian Wood
            ... I have a slug that s been running Debian from a flash drive for almost 3 years, no problems yet. I did set noatime, and I use almost no swap. It s not
            Message 5 of 16 , Mar 29 12:36 PM
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              On Monday 29 March 2010 12:38:26 pm Emil Granström wrote:
              > Hello. I am a newbie here using the slug.
              > I will be using the slug for temp meassurements using OWFS in our
              > cottage, I will generate graphs and alarms for critical temps.
              > I will be runing the slug from a 4GB USB thumbdrive. To reduce the
              > access of the disk I have done the "touch /.ext3flash" command.
              >
              > I assume this question is a bit hard to comment on but can anyone give
              > me a hint on what to expect when it comes to the lifecycle of the USB
              > drive ?
              > If the slug is on 24-7 how long can it be before I can expect problems ?
              > Are we talking week, months, years or what ?
              > I hope someone with a bit more handson experience can comment or share
              > some insights.

              I have a slug that's been running Debian from a flash drive for almost 3 years,
              no problems yet.

              I did set noatime, and I use almost no swap.

              It's not doing any heavy lifting, but it's been running 24/7.

              Not that this guarantees anything, just a datapoint.
            • stanley_p_miller_qaz
              ... I think you will find that the lifetime is not related to how long the drive is used but on how many times it is written to. If you design your programs so
              Message 6 of 16 , Mar 29 7:48 PM
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                --- In nslu2-linux@yahoogroups.com, Emil Granström <emilg@...> wrote:
                >
                > Hello. I am a newbie here using the slug.
                > I will be using the slug for temp meassurements using OWFS in our
                > cottage, I will generate graphs and alarms for critical temps.
                > I will be runing the slug from a 4GB USB thumbdrive. To reduce the
                > access of the disk I have done the "touch /.ext3flash" command.
                >
                > I assume this question is a bit hard to comment on but can anyone give
                > me a hint on what to expect when it comes to the lifecycle of the USB
                > drive ?
                > If the slug is on 24-7 how long can it be before I can expect problems ?
                > Are we talking week, months, years or what ?
                > I hope someone with a bit more handson experience can comment or share
                > some insights.
                >
                > Brg
                > Emil, in Sweden.
                >

                I think you will find that the lifetime is not related to how long the drive is used but on how many times it is written to. If you design your programs so that they save up data and only write it out when they are running low on RAM you'll greatly extend the lifetime over doing many more smaller writes.

                My slugs has been running off flash drives with no special setup beyond the wiki suggestions for several years now problems. One is on a 256 MB drive and one is on a 4 GB drive.

                I seem to recall reading a couple articles about larger flash drives (having more free space on the drive) also having longer lifetimes as the internal firmware can move the writes around and perform wear-leveling so no one spot gets written to often enough to fail early.
              • Emil Granström
                Thanks for all replies. I guess I can stop worrying about this. Brg Emil ... Thanks for all replies. I guess I can stop worrying about this. Brg Emil Brian
                Message 7 of 16 , Mar 29 11:45 PM
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                  Thanks for all replies.
                  I guess I can stop worrying about this.

                  Brg
                   Emil

                  Brian Wood wrote:
                   

                  On Monday 29 March 2010 12:38:26 pm Emil Granström wrote:
                  > Hello. I am a newbie here using the slug.
                  > I will be using the slug for temp meassurements using OWFS in our
                  > cottage, I will generate graphs and alarms for critical temps.
                  > I will be runing the slug from a 4GB USB thumbdrive. To reduce the
                  > access of the disk I have done the "touch /.ext3flash" command.
                  >
                  > I assume this question is a bit hard to comment on but can anyone give
                  > me a hint on what to expect when it comes to the lifecycle of the USB
                  > drive ?
                  > If the slug is on 24-7 how long can it be before I can expect problems ?
                  > Are we talking week, months, years or what ?
                  > I hope someone with a bit more handson experience can comment or share
                  > some insights.

                  I have a slug that's been running Debian from a flash drive for almost 3 years,
                  no problems yet.

                  I did set noatime, and I use almost no swap.

                  It's not doing any heavy lifting, but it's been running 24/7.

                  Not that this guarantees anything, just a datapoint.

                • Mike Westerhof (mwester)
                  ... I have a slug installed at an old house I have been working to refurbish. It uses a network of one-wire sensors to monitor temperature inside, but more
                  Message 8 of 16 , Mar 31 4:41 AM
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                    Emil Granström wrote:
                    > Hello. I am a newbie here using the slug.
                    > I will be using the slug for temp meassurements using OWFS in our
                    > cottage, I will generate graphs and alarms for critical temps.
                    > I will be runing the slug from a 4GB USB thumbdrive. To reduce the
                    > access of the disk I have done the "touch /.ext3flash" command.
                    >
                    > I assume this question is a bit hard to comment on but can anyone give
                    > me a hint on what to expect when it comes to the lifecycle of the USB
                    > drive ?
                    > If the slug is on 24-7 how long can it be before I can expect problems ?
                    > Are we talking week, months, years or what ?
                    > I hope someone with a bit more handson experience can comment or share
                    > some insights.
                    >

                    I have a slug installed at an old house I have been working to
                    refurbish. It uses a network of one-wire sensors to monitor temperature
                    inside, but more importantly it measures the temperature of a few water
                    pipes that are prone to freezing, and monitors the very old boiler to
                    alert me should it fail.

                    I use a 2 GByte flash drive -- the NSLU2 has been running without a
                    reboot or restart since early last fall.

                    By-the-way, I use SlugOS -- if you find Unslung to be too old and too
                    "non-linux" in nature, you might try installing SlugOS 5.3-beta and then
                    installing owfs from the "unstable" feeds.

                    -Mike (mwester)
                  • Emil Granström
                    Thanks Mike, Your use seems very much like mine. I am currently testing the Unslug build but I will certainly keep the SlugOS in mind. I will connect mine to a
                    Message 9 of 16 , Mar 31 5:13 AM
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                      Thanks Mike,
                      Your use seems very much like mine. I am currently testing the Unslug build but I will certainly keep the SlugOS in mind.
                      I will connect mine to a Dovado UMR with a Tellstick so I can use the Slug to turn on heating if I need to.
                      RRDtool is doing some graphs and the Dovado UMR is suppling the internet connection via a mobile broadband connection.
                      /Emil


                      Mike Westerhof (mwester) wrote:
                       

                      Emil Granström wrote:
                      > Hello. I am a newbie here using the slug.
                      > I will be using the slug for temp meassurements using OWFS in our
                      > cottage, I will generate graphs and alarms for critical temps.
                      > I will be runing the slug from a 4GB USB thumbdrive. To reduce the
                      > access of the disk I have done the "touch /.ext3flash" command.
                      >
                      > I assume this question is a bit hard to comment on but can anyone give
                      > me a hint on what to expect when it comes to the lifecycle of the USB
                      > drive ?
                      > If the slug is on 24-7 how long can it be before I can expect problems ?
                      > Are we talking week, months, years or what ?
                      > I hope someone with a bit more handson experience can comment or share
                      > some insights.
                      >

                      I have a slug installed at an old house I have been working to
                      refurbish. It uses a network of one-wire sensors to monitor temperature
                      inside, but more importantly it measures the temperature of a few water
                      pipes that are prone to freezing, and monitors the very old boiler to
                      alert me should it fail.

                      I use a 2 GByte flash drive -- the NSLU2 has been running without a
                      reboot or restart since early last fall.

                      By-the-way, I use SlugOS -- if you find Unslung to be too old and too
                      "non-linux" in nature, you might try installing SlugOS 5.3-beta and then
                      installing owfs from the "unstable" feeds.

                      -Mike (mwester)

                    • lance_benson
                      I ran an unslung slug for 2 and a half years off of a 512mb thumbdrive without problems--and without doing anything about swap (ymmv)--until I repurposed the
                      Message 10 of 16 , Mar 31 7:23 AM
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                        I ran an unslung slug for 2 and a half years off of a 512mb thumbdrive without problems--and without doing anything about swap (ymmv)--until I repurposed the slug (the drive is still working holding files for an mp3 player).

                        That said, openWrt can install completely in flash and do what you have said you want to do. I have 2 slugs in different locations doing that--monitoring temperatures and reading other sensors--no usb drive is needed. I don't use one-wire, tho--I communicate with a PICAXE microprocessor which reads the sensors and sends messages via serial to the slug--through a usb serial dongle.
                      • clerew5
                        ... Eh? What sort of sensor uses one wire? BTW, I have just wired up some premises with two-core cable, only to discover when I came to order the sensors that
                        Message 11 of 16 , Apr 1, 2010
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                          --- In nslu2-linux@yahoogroups.com, "Mike Westerhof (mwester)" <mwester@...> wrote:

                          > I have a slug installed at an old house I have been working to
                          > refurbish. It uses a network of one-wire sensors to monitor temperature
                          > inside, but more importantly it measures the temperature of a few water
                          > pipes that are prone to freezing, and monitors the very old boiler to
                          > alert me should it fail.

                          Eh? What sort of sensor uses one wire?

                          BTW, I have just wired up some premises with two-core cable, only to discover when I came to order the sensors that they needed 3-core :-( .
                        • Philip Tait
                          1-wire sensors: http://en.wikipedia.org/wiki/1-Wire
                          Message 12 of 16 , Apr 1, 2010
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                            1-wire sensors: http://en.wikipedia.org/wiki/1-Wire

                            On Thu, 2010-04-01 at 13:47 +0000, clerew5 wrote:
                            >
                            >
                            >
                            > --- In nslu2-linux@yahoogroups.com, "Mike Westerhof (mwester)"
                            > <mwester@...> wrote:
                            >
                            > > I have a slug installed at an old house I have been working to
                            > > refurbish. It uses a network of one-wire sensors to monitor
                            > temperature
                            > > inside, but more importantly it measures the temperature of a few
                            > water
                            > > pipes that are prone to freezing, and monitors the very old boiler
                            > to
                            > > alert me should it fail.
                            >
                            > Eh? What sort of sensor uses one wire?
                            >
                            > BTW, I have just wired up some premises with two-core cable, only to
                            > discover when I came to order the sensors that they needed
                            > 3-core :-( .
                            >
                            >
                            >
                            >
                            >
                          • clerew5
                            ... Ah, but that actually requires 2-wires :-( . And it would seem that the idea is to put the A-D converter at the far end of some wire alongside the sensor.
                            Message 13 of 16 , Apr 2, 2010
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                              --- In nslu2-linux@yahoogroups.com, Philip Tait <pjtait@...> wrote:
                              >
                              > 1-wire sensors: http://en.wikipedia.org/wiki/1-Wire

                              Ah, but that actually requires 2-wires :-( .

                              And it would seem that the idea is to put the A-D converter at the far end of some wire alongside the sensor.

                              And how does one interface that to a Slug? Can it be done from an i2c bus, or is it necessary to bring out the UART connection from the Slug? And can somebody recommend a suitable sensor/converter for use with that system (I am looking for a temperature resolution of 0.1°C, and an absolute accuracy not too much worse than that).

                              I would also like some advice on the path I have been following so far:

                              I intended to attach an i2c bus (that seems a well-established hack to the Slug). On that bus there will be assorted LEDs and pushbuttons, an LCD, an EEPROM, and a 4-channel 12-bit A-D converter. I had intended to use LM35DZ temperatures sensors (as manufactured by both MS and Texas). And I had identified an i2c A-D chip from the Farnell website (AD7991) that appeared to have all the required characteristics.

                              But I did not check enough. It turned out to be a SOT23 style chip which was about the size of a baby's fingernail :-( . Not nice for building on a breadboard. I looked for a suitable breakout board, but the only available one for an 8-pin SOT23 was in California, and I am in the UK. The only breakout boards readily available in the UK are for 6-pin SOTs (well, there is a possible one from Microchip, but at a ridiculous price).

                              So back to the Farnell website for a chip with a larger footprint. But they all seem of be surface mount and with TSSOP or MSOP format, where the pin spacing is still 0.025in (the same as SOT23).

                              So can anyone suggest any better chip? I might get away with SOIC format (0.05in spacing). The only chips I can find with good ol' DIL fomat are from Microchip, and they use Yet Another Nonstandard Interface (Microport).
                              >
                              > On Thu, 2010-04-01 at 13:47 +0000, clerew5 wrote:

                              > > --- In nslu2-linux@yahoogroups.com, "Mike Westerhof (mwester)"
                              > > <mwester@> wrote:
                              > >
                              > > > I have a slug installed at an old house I have been working to
                              > > > refurbish. It uses a network of one-wire sensors to monitor
                              > > temperature...
                              > >
                              > > Eh? What sort of sensor uses one wire?
                            • Mike Westerhof
                              ... Indeed. Apparently somebody thought that it might be possible to use the ground in a building, for example, as the return conductor. I think that s
                              Message 14 of 16 , Apr 2, 2010
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                                clerew5 wrote:
                                > --- In nslu2-linux@yahoogroups.com, Philip Tait <pjtait@...> wrote:
                                >
                                >> 1-wire sensors: http://en.wikipedia.org/wiki/1-Wire
                                >>
                                >
                                > Ah, but that actually requires 2-wires :-( .
                                >

                                Indeed. Apparently somebody thought that it might be possible to use
                                the ground in a building, for example, as the return conductor. I think
                                that's marketing talk, as the devices really work better with a proper
                                2-wire system.

                                > And it would seem that the idea is to put the A-D converter at the far end of some wire alongside the sensor.
                                >

                                Yes. The wire (or pair of conductors, if you prefer) is actually a
                                digital network connection. Many of the devices do A-D conversion, and
                                send the results digitally back to the host. However, some devices are
                                completely digital. And some do the reverse -- I have a relay board
                                that I intend to use to control the heating/cooling system once I finish
                                this project, although right now it just blinks LEDs and looks cool -
                                everyone likes blinking lights ;-).

                                > And how does one interface that to a Slug? Can it be done from an i2c bus, or is it necessary to bring out the UART connection from the Slug? And can somebody recommend a suitable sensor/converter for use with that system (I am looking for a temperature resolution of 0.1°C, and an absolute accuracy not too much worse than that).
                                >

                                I use a pre-packaged USB device:
                                http://www.hobby-boards.com/catalog/product_info.php?cPath=23&products_id=1503

                                > I would also like some advice on the path I have been following so far:
                                >
                                > I intended to attach an i2c bus (that seems a well-established hack to the Slug). On that bus there will be assorted LEDs and pushbuttons, an LCD, an EEPROM, and a 4-channel 12-bit A-D converter. I had intended to use LM35DZ temperatures sensors (as manufactured by both MS and Texas). And I had identified an i2c A-D chip from the Farnell website (AD7991) that appeared to have all the required characteristics.
                                >
                                > But I did not check enough. It turned out to be a SOT23 style chip which was about the size of a baby's fingernail :-( . Not nice for building on a breadboard. I looked for a suitable breakout board, but the only available one for an 8-pin SOT23 was in California, and I am in the UK. The only breakout boards readily available in the UK are for 6-pin SOTs (well, there is a possible one from Microchip, but at a ridiculous price).
                                >
                                > So back to the Farnell website for a chip with a larger footprint. But they all seem of be surface mount and with TSSOP or MSOP format, where the pin spacing is still 0.025in (the same as SOT23).
                                >
                                > So can anyone suggest any better chip? I might get away with SOIC format (0.05in spacing). The only chips I can find with good ol' DIL fomat are from Microchip, and they use Yet Another Nonstandard Interface (Microport).
                                >

                                Check out the kits and parts at the supplier I listed above. That will
                                give you some idea about size and nature of the various one-wire chips
                                and devices, and from that you can decide if the one-wire parts are more
                                practical.

                                In terms of the temperature sensors, I needed a network of them, and
                                found that the pre-packaged or kitted parts were all too expensive -- I
                                was paying more for connectors than the parts. So I purchased a dozen
                                of the temperature sensors from a taiwan-based supplier (via eBay).
                                Each part is in a small transistor package, and were very easy to solder
                                to short (8 inches approx) twisted pair.

                                Each "pigtail" was tested, and the network address recorded. I attached
                                a label with the network address to the pigtail as well -- otherwise you
                                have no idea which sensor is which (they are, of course, wired up to
                                the same twisted pair).

                                I wired the building up with ordinary telephone twisted pair, running a
                                length through the first-floor rooms, then dragging it through the
                                crawlspace beneath the building to get a sensor down where the plumbing
                                is at most risk of freezing.

                                I estimate the total cost for that part of the system to be about USD 3
                                per sensor, by the time I was done with the sensors, solder, and
                                telephone wire. Hard to beat that for price.

                                -Mike (mwester)

                                >> On Thu, 2010-04-01 at 13:47 +0000, clerew5 wrote:
                                >>
                                >
                                >
                                >>> --- In nslu2-linux@yahoogroups.com, "Mike Westerhof (mwester)"
                                >>> <mwester@> wrote:
                                >>>
                                >>>
                                >>>> I have a slug installed at an old house I have been working to
                                >>>> refurbish. It uses a network of one-wire sensors to monitor
                                >>>>
                                >>> temperature...
                                >>>
                                >>> Eh? What sort of sensor uses one wire?
                                >>>
                                >
                                >
                                >
                                >
                                > ------------------------------------
                                >
                                > Yahoo! Groups Links
                                >
                                >
                                >
                                >
                                >
                              • clerew5
                                ... Yes, there seems to be some neat stuff there. But I am already well down the i2c route. Actually, I have now reached the conclusion that the easiest way to
                                Message 15 of 16 , Apr 5, 2010
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                                  --- In nslu2-linux@yahoogroups.com, Mike Westerhof <mwester@...> wrote:

                                  > > But I did not check enough. It turned out to be a SOT23 style chip which was about the size of a baby's fingernail :-( . Not nice for building on a breadboard. I looked for a suitable breakout board, but the only available one for an 8-pin SOT23 was in California, and I am in the UK. The only breakout boards readily available in the UK are for 6-pin SOTs (well, there is a possible one from Microchip, but at a ridiculous price).
                                  > >
                                  > > So back to the Farnell website for a chip with a larger footprint. But they all seem of be surface mount and with TSSOP or MSOP format, where the pin spacing is still 0.025in (the same as SOT23).
                                  > >
                                  > > So can anyone suggest any better chip? I might get away with SOIC format (0.05in spacing). The only chips I can find with good ol' DIL fomat are from Microchip, and they use Yet Another Nonstandard Interface (Microport).
                                  > >
                                  >
                                  > Check out the kits and parts at the supplier I listed above. That will
                                  > give you some idea about size and nature of the various one-wire chips
                                  > and devices, and from that you can decide if the one-wire parts are more
                                  > practical.

                                  Yes, there seems to be some neat stuff there. But I am already well down the i2c route.

                                  Actually, I have now reached the conclusion that the easiest way to embed surface mounted chips (even the very small ones) is to manufacture a one-off PCB. This turns out to be much easier that one might have thought. Google turns up lots of advice. All you need is a laser printer, some suitable transfer paper (old glossy magazines are recommended), and a willingness to handle ferric chloride etch (which is pretty messy stuff by all accounts).
                                • Thomas Cooper
                                  It s much easier to buy what you need ready to go from Spark Fun Electronics, or some place similar... They cost about a buck or so. A bottle of ferric cloride
                                  Message 16 of 16 , Apr 5, 2010
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                                    It's much easier to buy what you need ready to go from Spark Fun Electronics, or some place similar... They cost about a buck or so. A bottle of ferric cloride will cost you more than that.

                                    On Mon, Apr 5, 2010 at 4:09 AM, clerew5 <clerew5@...> wrote:
                                     


                                    --- In nslu2-linux@yahoogroups.com, Mike Westerhof <mwester@...> wrote:

                                    > > But I did not check enough. It turned out to be a SOT23 style chip which was about the size of a baby's fingernail :-( . Not nice for building on a breadboard. I looked for a suitable breakout board, but the only available one for an 8-pin SOT23 was in California, and I am in the UK. The only breakout boards readily available in the UK are for 6-pin SOTs (well, there is a possible one from Microchip, but at a ridiculous price).
                                    > >
                                    > > So back to the Farnell website for a chip with a larger footprint. But they all seem of be surface mount and with TSSOP or MSOP format, where the pin spacing is still 0.025in (the same as SOT23).
                                    > >
                                    > > So can anyone suggest any better chip? I might get away with SOIC format (0.05in spacing). The only chips I can find with good ol' DIL fomat are from Microchip, and they use Yet Another Nonstandard Interface (Microport).
                                    > >
                                    >
                                    > Check out the kits and parts at the supplier I listed above. That will
                                    > give you some idea about size and nature of the various one-wire chips
                                    > and devices, and from that you can decide if the one-wire parts are more
                                    > practical.

                                    Yes, there seems to be some neat stuff there. But I am already well down the i2c route.

                                    Actually, I have now reached the conclusion that the easiest way to embed surface mounted chips (even the very small ones) is to manufacture a one-off PCB. This turns out to be much easier that one might have thought. Google turns up lots of advice. All you need is a laser printer, some suitable transfer paper (old glossy magazines are recommended), and a willingness to handle ferric chloride etch (which is pretty messy stuff by all accounts).


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