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</o:shapelayout></xml><![endif]--></head><body lang=FR-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Very interesting as an approach..<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I’ll put that in my list of possible solutions !<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Many thanks !<br>JP<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=FR style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De :</span></b><span lang=FR style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> cheater cheater [mailto:cheater00social@gmail.com] <br><b>Envoyé :</b> 24 mars 2021 14:42<br><b>À :</b> Jean-Pierre Desrochers<br><b>Cc :</b> SDIY List<br><b>Objet :</b> Re: [sdiy] Very cheap SPI pressure sensors.. anybody ??<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>So you have your piano roll going from bottom to top (or top to bottom, doesn't matter) and you want to read horizontal rows of holes. Behind the roll you have a wand with holes that produces air pressure. That works as it would in a normal player piano, i'm guessing you have it worked out already. In front of it, you would have a metal beam going horizontally, then from that you would have tiny strips of (rigid) foil hanging off of it, in front of the row you're looking to measure. They are attached using a piece of fabric, or even a few pieces of thread, attached to the piece of foil using tape, as well as attached to the beam using tape. the bare metal surface without tape on it should be facing away from the roll. that's where the pcb with capacitive sensing pads is located. you use that to sense the capacitance. that's all there is to it, really. you add enough weight to the foil strip that it gets deflected by the air, but goes straight back when there's no hole (and no air).<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>So looking from the side:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Blower: -><o:p></o:p></p></div><div><p class=MsoNormal>Piano roll: |<o:p></o:p></p></div><div><p class=MsoNormal>Foil strip: #<o:p></o:p></p></div><div><p class=MsoNormal>Capacitive sensing pcb: H<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>it would look like this:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>-> | # H<o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Wed, Mar 24, 2021 at 6:43 PM Jean-Pierre Desrochers <<a href="mailto:jpdesroc@oricom.ca">jpdesroc@oricom.ca</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>>I take it back, actually. You could do exactly what I propose with very light foil suspended so it can move depending on the air. It would be extremely, extremely cheap, and given you >only really need on/off >you should be perfectly fine there.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Yeah.. I was trying to figure out some vacuum/mechanical movement sensors<br>that would do exactly what you bring as a solution..</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>But how to achieve that ??<br>I thought about a small moving stick that is inside a vertical hose<br>resting down when no air flows but sucked up on any vacuum.<br>Then optics could check for any ON/OFF movement..</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De :</span></b><span lang=EN-CA style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> cheater cheater [mailto:<a href="mailto:cheater00social@gmail.com" target="_blank">cheater00social@gmail.com</a>] <br><b>Envoyé :</b> 24 mars 2021 13:10<br><b>À :</b> Jean-Pierre Desrochers<br><b>Cc :</b> Didrik Madh</span><span lang=FR style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>eden; SDIY List<br><b>Objet :</b> Re: [sdiy] Very cheap SPI pressure sensors.. anybody ??</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I take it back, actually. You could do exactly what I propose with very light foil suspended so it can move depending on the air. It would be extremely, extremely cheap, and given you only really need on/off you should be perfectly fine there.<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On Sat, Mar 20, 2021 at 5:30 PM cheater cheater <<a href="mailto:cheater00social@gmail.com" target="_blank">cheater00social@gmail.com</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid windowtext 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt;border-color:currentcolor currentcolor currentcolor rgb(204,204,204)'><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>oh, you meant air pressure sensor... sorry... i thought you meant polyphonic aftertouch.<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On Fri, Mar 19, 2021 at 10:34 PM Jean-Pierre Desrochers <<a href="mailto:jpdesroc@oricom.ca" target="_blank">jpdesroc@oricom.ca</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid windowtext 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt;border-color:currentcolor currentcolor currentcolor rgb(204,204,204)'><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>></span></b><b><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>As for the option of light sensing, the assumption of freedom to design, would allow you to simply have an array of LEDs directly on the top and a array of sensors directly under, >mounted on boards. To me at >least, using optical fibers for this purpose and placing the sensing elsewhere seems like an overcomplication. Unless there's some design requirement I'm not seeing</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>An optic based reader would look about like this:</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><img border=0 width=388 height=258 id="gmail-m_9164436443445347876gmail-m_-8553135462245313061gmail-m_5580949261223597849Image_x0020_1" src="cid:image001.jpg@01D72161.948DE330"></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Notice the big horizontal LEDs bar over the row of holes in reading..</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Not very nice..</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>On the other hand a vacuum based reader would look like the original thing:</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><img border=0 width=381 height=233 id="gmail-m_9164436443445347876gmail-m_-8553135462245313061gmail-m_5580949261223597849Image_x0020_3" src="cid:image002.jpg@01D72161.948DE330"></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>The rolling mechanism will be using a DC brushless speed controlled motor<br>connected to the right gears assembly.</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'><b><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>>I would consider designing boards where you have the sensors in a row on the board. You could for example have 15 sensors per board and 6 groups for the target of of 90. You could >then either >have a multiplexing arrangement like the one I suggested, or a microcontroller on each board for local processing. <br></span></b><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>This is about the way I was thinking to do it..</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>>You could then have a physical piece (3D printed or >otherwise fabricated) that fits over the board to create a chamber for each sensor.</span></b><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Very good idea ! My first ideas were to glue very small silicon hoses over each sensors<br>but a separate chamber for each sensor is much better..<br>These chambers could have a small pointing upward ‘chimney’ to insert<br>the vacuumed hoses. About like this housing:</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><img border=0 width=276 height=225 id="gmail-m_9164436443445347876gmail-m_-8553135462245313061gmail-m_5580949261223597849Image_x0020_4" src="cid:image003.png@01D72161.948DE330"></span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>And by the way, this reader will have its own audio player<br>playing ‘honkytonk’ sounding notes with a MIDI output !</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-CA style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> </span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><b><span lang=FR style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De :</span></b><span lang=FR style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> Didrik Madheden [mailto:<a href="mailto:nitro2k01@gmail.com" target="_blank">nitro2k01@gmail.com</a>] <br><b>Envoyé :</b> 19 mars 2021 16:13<br><b>À :</b> Jean-Pierre Desrochers<br><b>Cc :</b> SDIY List<br><b>Objet :</b> Re: [sdiy] Very cheap SPI pressure sensors.. anybody ??</span><o:p></o:p></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>So that gives me one important piece of information: the sensors could be placed in a linear pattern, as opposed to, for example, being spread out and needing to be wired up individually. <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I would consider designing boards where you have the sensors in a row on the board. You could for example have 15 sensors per board and 6 groups for the target of of 90. You could then either have a multiplexing arrangement like the one I suggested, or a microcontroller on each board for local processing. You could then have a physical piece (3D printed or otherwise fabricated) that fits over the board to create a chamber for each sensor.<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>I'm assuming here that this is a machine that you are either designing from scratch, or have relative freedom to modify. In particular that you control fully what's above and below the line of notes that's currently being read. But from the rest of your description I realize that this may not be the case. Are you for example retrofitting an old machine, or you feel that you want to be true to the original principles? Or do you just want a solution that works for as cheap as possible?<o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'> <o:p></o:p></p></div><div><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'>As for the option of light sensing, the assumption of freedom to design, would allow you to simply have an array of LEDs directly on the top and a array of sensors directly under, mounted on boards. To me at least, using optical fibers for this purpose and placing the sensing elsewhere seems like an overcomplication. Unless there's some design requirement I'm not seeing...<br><br>/Didrik<o:p></o:p></p><div><div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>On Fri, Mar 19, 2021, 20:27 Jean-Pierre Desrochers <<a href="mailto:jpdesroc@oricom.ca" target="_blank">jpdesroc@oricom.ca</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid windowtext 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0cm;margin-bottom:5.0pt;border-color:currentcolor currentcolor currentcolor rgb(204,204,204)'><p class=MsoNormal style='mso-margin-top-alt:auto;margin-bottom:12.0pt'>Good idea here Didrick !<br>But a little too complicated for my design..<br>This futur project is a piano roll scanner/player.<br>This has been a project done many times by DIYers all over the place<br>but they mostly used optical approach to read paper holes<br>(fiber optics + photo-transistors).<br>This needs a LED array bar put over the rolling paper holes rows<br>for the fiber optics holes detections, which I don't like at all..<br>I'd like better to read the punched holes using vacuumed air<br>like antique piano did. A small vacuum pump will do that.<br>This is why I'd use pressure sensors to detect any holes<br>coming up while the paper roll is playing.<br>But I'm still looking any design possibilities.<br>I'll need around 90 sensors (SPI communications) to get the job done.<br>This will obviously need some multiplexing to access each of them.<br>Doable..<br><br><br>-----Message d'origine-----<br>De : Didrik Madheden [mailto:<a href="mailto:nitro2k01@gmail.com" target="_blank">nitro2k01@gmail.com</a>] <br>Envoyé : 19 mars 2021 14:16<br>À : Jean-Pierre Desrochers<br>Cc : SDIY List<br>Objet : Re: [sdiy] Very cheap SPI pressure sensors.. anybody ??<br><br>Here's an idea. It's a bit janky, and requires some extra circuitry, but it might work for you. The basic idea is to use a chain of 74hc595 serial to parallel shift registers to generate either a chip select or clock signal. You feed in a single 0 into the shift register, which you move forward one step at a time.<br><br>In the case of a chip select signal, this selects one chip at a time.<br>To select the next chip, clock the register chain one step to forward the 0 bit one step.<br><br>In the case of a clock signal, it's a bit more complicated. But this could be used to multiplex I2C. In this configuration, all the data pins are commoned. (Or commoned in multiple groups if needed for signal integrity.) You have a similar idea as in the example above in that a 0 bit travels one step at a time. You could do this the slow way and send out the full chain of bits just to flip one bit and clock the local I2C bus. Or, you could do it the slightly quicker way and use the output enable of the 74HC595's to clock the selected device.<br>It would work like this:<br><br>Most bits in the register are ones. For those bits, turning the output enable on or off would do nothing because you're switching between driving the clock signal high, or leaving the clock signal with a pullup resistor which also keeps at logic high.<br><br>One or multiple bits are zeros. When output enable is off, that output is high from the pullup that you add, or which exists on the module you use. When you turn on the output enable, voilà! The clock signal for that device goes low, and you have fed clocked one I2C bit. I think you can fill in the rest. All the other devices will also see the data line change, but they're in high impedance mode, and will not react to data without a corresponding clock.<br><br>If you are able to design a board and have it ordered from JLCPCB using their PCB assembly service, you could use SPL06-007. It costs, currently, $0.6622/pc in 100 quantity. There's some extra cost for the board and assembly service, but that should be relatively cheap in comparison.<br><br>To give even more precise advice, it would also help to know more about the details of the project. In particular the physical arrangement of the sensors. If they need to branch off from a central point using cables, if the cables need to be detachable etc. If you want to discuss these things closer in private, feel free to contact me off-list.<br><br>/Didrik<br><br>On Fri, 19 Mar 2021 at 16:14, Jean-Pierre Desrochers <<a href="mailto:jpdesroc@oricom.ca" target="_blank">jpdesroc@oricom.ca</a>> wrote:<br>><br>> I'm looking for very cheap SPI pressure sensors (around $1.00 a piece <br>> or less)<br>><br>> For a future project. The pressure value doesn't matter but the size and cost do.<br>><br>> I will need around 90 of these sensors.<br>><br>><br>><br>> For example I found this:<br>><br>> BMP180 GY-68 GY68 3.3V 5V BMP-180 Temperature Pressure Sensor Module <br>> Barometric IIC I2C Interface Sensor Module Replace BMP085 $0.90CAD<br>><br>> <a href="https://www.aliexpress.com/item/32832330585.html?src=google&albch=shop" target="_blank">https://www.aliexpress.com/item/32832330585.html?src=google&albch=shop</a><br>> ping&acnt=708-803-3821&isdl=y&slnk=&plac=&mtctp=&albbt=Google_7_shoppi<br>> ng&aff_platform=google&aff_short_key=UneMJZVf&&albagn=888888&isSmbAuto<br>> Call=false&needSmbHouyi=false&albcp=7386552844&albag=80241711349&trgt=<br>> 743612850714&crea=en32832330585&netw=u&device=c&albpg=743612850714&alb<br>> pd=en32832330585&gclid=CjwKCAjw9MuCBhBUEiwAbDZ-7mU2hTS0J2DLxvsPsj8F40L<br>> -zV8vtApw9ds_ks1c2Qjg7dLiKgsy3RoCq-EQAvD_BwE&gclsrc=aw.ds<br>><br>> But because I need 90 devices and the BMP180 is I2C and has only one <br>> address value I would need somekind of multiplexer to address 90 devices (one at the time obviously).<br>><br>> So.. SPI devices would fit better here.<br>><br>><br>><br>> One other possibility would be to use this type:<br>><br>> MPS20N0040D MPS20N0040D-D Sphygmomanometer Dip Air Pressure Sensor 0-40kPa DIP-6 For Arduino Raspb $0.74CAD<br>><br>> <a href="https://www.aliexpress.com/item/4000354356373.html?src=google&albch=sh" target="_blank">https://www.aliexpress.com/item/4000354356373.html?src=google&albch=sh</a><br>> opping&acnt=708-803-3821&isdl=y&slnk=&plac=&mtctp=&albbt=Google_7_shop<br>> ping&aff_platform=google&aff_short_key=UneMJZVf&&albagn=888888&isSmbAu<br>> toCall=false&needSmbHouyi=false&albcp=9604672960&albag=100679328364&tr<br>> gt=296904913880&crea=en4000354356373&netw=u&device=c&albpg=29690491388<br>> 0&albpd=en4000354356373&gclid=CjwKCAjw9MuCBhBUEiwAbDZ-7kff0q--0F6YUo73<br>> aVqE_HAtqkRyIslFbEMRTWz7QICR2szctlC7zxoCrMUQAvD_BwE&gclsrc=aw.ds<br>><br>><br>><br>> But I’ll need some analog IC to manage the output..<br>><br>> Again the part’s pressure specs value do not matter.. I will manage a way to use it.<br>><br>> but the size and cost do.<br>><br>><br>><br>> So far the best would be a SPI equivalent of the BMP180 IC..<br>><br>> Let me know if someone googled something I did not spot !<br>><br>><br>><br>> JP<br>><br>> _______________________________________________<br>> Synth-diy mailing list<br>> <a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br>> <a href="http://synth-diy.org/mailman/listinfo/synth-diy" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a><br>> Selling or trading? Use <a href="mailto:marketplace@synth-diy.org" target="_blank">marketplace@synth-diy.org</a><br><br><br><br>--<br>/Didrik<o:p></o:p></p></blockquote></div></div></div></div></div><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'>_______________________________________________<br>Synth-diy mailing list<br><a href="mailto:Synth-diy@synth-diy.org" target="_blank">Synth-diy@synth-diy.org</a><br><a href="http://synth-diy.org/mailman/listinfo/synth-diy" target="_blank">http://synth-diy.org/mailman/listinfo/synth-diy</a><br>Selling or trading? Use <a href="mailto:marketplace@synth-diy.org" target="_blank">marketplace@synth-diy.org</a><o:p></o:p></p></blockquote></div></blockquote></div></div></div></blockquote></div></div></body></html>