Geerinckx Posted December 28, 2006 Report Share Posted December 28, 2006 Hi!I have a problem with the touch sensor:When i don't connect the ltc module to the pc and i dont touch sensor, the inputs stays at 127 en when i touch it goes 0,127,0,127,0,127......When i connect the Ltc module to the pc the input stays 127 also when i touch it!I also tried to connect Vs to the ground of a power socket, en connect Vs to my skin but nothing helps!Do you have sugestions to solve this problem?X-Mass GrtzzGert Quote Link to comment Share on other sites More sharing options...
SLP Posted December 28, 2006 Report Share Posted December 28, 2006 Often those sensors have a different pinning as usual pots.Be sure to have the sensor connected right. Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 28, 2006 Author Report Share Posted December 28, 2006 Thx for the fast replyBut there isn't a pot! i use just a wire with at the end a coper plate!grttzzGert Quote Link to comment Share on other sites More sharing options...
doc Posted December 29, 2006 Report Share Posted December 29, 2006 This is really a strange behaviour.I need a little more information:For what purpose do you use the LTC module?Just as a Monitor or do you use also the serial port?When the LTC is plugged in: What is the behaviour of the other controls ( knobs, pots ...). Is a normal knob changing its value by pressing it or not?greetsDoc Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 29, 2006 Author Report Share Posted December 29, 2006 Hi DocThe LTC modules is for connection to the Pc with the rs232 port!The behavior of the other stuf is normal! pot's all work buttons to!But i was thinking, for the testing purpose i only stuffed 1 * 74hc165of thad DIN, the other DIN (MIDIBOX 64) is fully stufedI connected the serial input to the serial output with a wire! of the not stuffed 74hc165 but it is in the end of the row:______ _______________ ____________________________| Core | -------> | DIN full stuffed | -------> |DIN first 74hc165 stuffed others|-------- ------------------ | Connected true with a wire! | --------------------------------Is thad maybe the problem?X-mass greetings To all midi-boxersGert Quote Link to comment Share on other sites More sharing options...
SLP Posted December 29, 2006 Report Share Posted December 29, 2006 Often those sensors have a different pinning as usual pots.I meant "compared to usual pots" so you want your touch sensor to act like a analog controller...But it this case you have to connect it to the AIN , not to the DIN Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 29, 2006 Author Report Share Posted December 29, 2006 Hi SLPNo i just wonne have a DIN to trigger some buttons on my pc!i'm a light jocky in a club and i wonna replace the old controller to a pc based controller! but without a hardware solution it is not possible!So i use the touch sensors for really quick flashes en shutters for the pars, strobescans, & movingheads!GrtzzGert Quote Link to comment Share on other sites More sharing options...
audiocommander Posted December 29, 2006 Report Share Posted December 29, 2006 - if you have built an active LTC module, I expect you removed the optocoupler from the Core?- does it work if you leave out the full stuffed DINx4 board and connect only the board your touch-sensor is connected to?regards,Michael Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 29, 2006 Author Report Share Posted December 29, 2006 Hi audiocommanderNope nothing changes! stil 0,127,0,127.....en when i connect myself to the 0V it stays at 127GrtzzGertps: I connected the input of the other 3 schift registers with a wire to the output Is this correct? or should it be resistors? Quote Link to comment Share on other sites More sharing options...
audiocommander Posted December 29, 2006 Report Share Posted December 29, 2006 en when i connect myself to the 0V it stays at 127hmm... I don't understand that part ;DI thought it works if the LTC is not connected (0 + 127): For a button, this would be the expected behaviour. Now when you connect the LTC you only get 127, is that right?That means the error should be at the LTC or the DIN-module or the optocoupler.I connected the input of the other 3 schift registers with a wire to the output. Is this correct?The DINx4 modules have to be chained. That means: Core J9 --> J1 DIN#1 J2 --> J1 DIN#2What I meant was to leave out the first DINx4 module to see if the error is located at the second DIN.Can you make a photo and attach it?In the meanwhile you could go through all the wirings and check them against the plans available @ uCApps.de; I think it sounds like a wiring issue...best regards,Michael Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 29, 2006 Author Report Share Posted December 29, 2006 ltc not connected:when i dont do a thing it stays at 127When i touch it is changes from 0,127,0,127...........When i clamp myself to the 0V it stays at 127When i connect the ltc:dont' touch it stays 127when i touch it, it also stays at 127also with skin connected to 0V it stays 127Jah i knew what you mentiontBut everything else works! alls DIN's & AIN'sso i disconected the stuffed module en connected only the module with 1 74hc165but nothing is differenti don't use an optocoupler becaus i use an LTC moduleGrtzzGert Quote Link to comment Share on other sites More sharing options...
audiocommander Posted December 29, 2006 Report Share Posted December 29, 2006 Okay, we're getting at it, I think everything is working fine: What exactly are you using as "Touch Sensor"? Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 29, 2006 Author Report Share Posted December 29, 2006 just a wire with a plug un the endjust for testingDoes it make anny difference? Quote Link to comment Share on other sites More sharing options...
audiocommander Posted December 29, 2006 Report Share Posted December 29, 2006 This will not work. And if it works, I'd be astonished.You need a capacity based touch sensor circuit (search for "Quantum QProx QT113") or if you want to stay connected while touching: a skin resistance circuit. Last one is probably the easiest: If you measure your skin resistance with a multimeter, you'll find out, that your skin as about 1 M to 20 M. If you look here: http://www.midibox.org/dokuwiki/doku.php?id=sensors and http://www.midibox.org/forum/index.php?topic=6506.0 you should be able to connect a basic skin restisance sensor. The topic was meant to be used on a AIN, but it's so easy, I think you'll be able to adapt it for a digital ON/OFF signal...However, I'd use a capacity based circuit, because you don't need to be wired. Just google around a bit and you should find plenty of touch circuits for switches!:)cheers,Michael Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 29, 2006 Author Report Share Posted December 29, 2006 i already tryed the QT160 i have him here with me but it works to slow and i cant touch 2 pats at the same timein this aticle http://www.midibox.org/forum/index.php?topic=4136.0it saise it would work with just cheap etched board!GrtzzGert Quote Link to comment Share on other sites More sharing options...
audiocommander Posted December 29, 2006 Report Share Posted December 29, 2006 so you connected it exactly like described here: http://www.ucapps.de/mbhp/mbhp_din_touchsensors.pdf ?And what kind of application are you using (eg MB64(e) ?)Does anyone know if J14 functionality is supported in all apps?Best regards,Michael Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 29, 2006 Author Report Share Posted December 29, 2006 Yes exactly the same!I only connected 2 sensors the others to the ground of thad 74hc165Or is thad maybe a mistake??I'm using MB64 I pretty sure J14 is supportedwhen i disconect J14 is gives all random information...........GreetingGert ps: thx for your time en help Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 29, 2006 Author Report Share Posted December 29, 2006 I get crazy from it!Strange thad it works whith the other fellows but not with me!I don't have to modify the code in the pic, am i correct?GrtzzGert Quote Link to comment Share on other sites More sharing options...
audiocommander Posted December 29, 2006 Report Share Posted December 29, 2006 Strange thad it works whith the other fellows but not with me!Well, as you can read on the second page of the topic you are referring to, similar problems like yours occured. I bet it behaves exactly the same if JazzyPidjay would connect an LTC module!So I think it's rather a basic construction error:1- the first problem i have encountered is when i touch a sensor the message 0,127,0,127,0,127... was send in loop to resolve this problem i have simply connect the 0v of the midibox to the ground.2- ok at this stade, when i touch a sensor it send correctly the values like a button. (but very quickly and intuitively) but when i touch to or more sensors, there's no more message send or messages are send randomely.to fix this problem, i simply plug myself with a jack in the belt directly to my skin connected to the groundNow my body was perfectly at 0v, the computer & the midibox also !! and i can touch 32 or more sensors, without any problem, like a button.i search a better way to solve this problem, but for now i plug (myself) & play ;DThis all sounds like grounding/shielding issues. Normally the touch sensing pin J14 is used for motorfaders (see "Touch Sensors" on the MBHP MF page: http://www.ucapps.de/mbhp_mf.html ; there's also a very detailed explanation by TK here: http://www.midibox.org/forum/index.php?topic=1544.0 ). You don't need to ground yourself to get that working! So either the MB64 application is not configured to use that kind of feature (don't know that, 'cause I go no MB64) or there is a basic mistake about your implementation of the touchDetection.Why don't you use a normal button switch to test if your basic equipment is working; then you could resume experimenting with different touch detection circuits! J14 is not the only possibility to get that kind of feature...Best regards,Michael Quote Link to comment Share on other sites More sharing options...
doc Posted December 29, 2006 Report Share Posted December 29, 2006 I'm also unsure if J14 is supported for touchsensors in other applications than the LC.With Midibox LC it is definitly working (for the touchsensors of the motorfaders). But I also have to connect myself to ground before I touch a fader.You changed the resistors correctly for the Touchsensor-DIN (no 10k resistors there?).Another thing:J14 (RD4 on the PIC) sits directly beneath the RX Pin. Have you checked these connections? Is there perhaps a short or something else between J14 and RX/TX. This would be the only "harware" explenation for the LTC / Touch behavoiur.greetsDoc Quote Link to comment Share on other sites More sharing options...
audiocommander Posted December 29, 2006 Report Share Posted December 29, 2006 I just experimented with a QT113 and found that it's a great chip to use touchDetection: I don't know why you experienced a slow response with the QT160 AFAICS it's the same as the QT113 but just multichannel (QT113: http://de.farnell.com/jsp/endecaSearch/partDetail.jsp?SKU=9775749 ). I checked it with an LED and cannot determine any slow behaviour... maybe you got the wrong Cap-Values?Best regards,Michael Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 30, 2006 Author Report Share Posted December 30, 2006 Hi guy'sThx for all the reply'si did experimented with the QT160! but i cant touch 2 buttons at the same time!and the respons time is to slow! maybe a 20MHz istead of a 10MHz will do the trick! I used 33µF capps for the inputs but i think de cap doesn't affects the speed of it it just changes the sensetivity! correct me if i'm wrong :-X ??? ;DI tested everything with buttons and everything works fine!10K pull-ups are gone to!I do think Touch Sensors are sepported in MB64 becaus you can adjust the sensetivity in the main asm file and in the sysex editor for the MB64I will search for a bad grounding, but i think i gonna find nothing i tripple checked everything, but ones again doesn't harms annybody 8) ::)Yes i think i gonne search for an other solution if this doesnt worksX-mass greetingGert Quote Link to comment Share on other sites More sharing options...
audiocommander Posted December 30, 2006 Report Share Posted December 30, 2006 Hi Gert,the respons time is to slow! maybe a 20MHz istead of a 10MHz will do the trick! I used 33µF capps for the inputs but i think de cap doesn't affects the speed of it it just changes the sensetivity! correct me if i'm wrongthe response times of the QT160 and the QT113 are different: point 2.1.6. of the datasheet explains this for the QT160:Response time is fixed at 99ms at a 10 MHz clock. Response time cna be altered by changing the clock frequency. Doubling the recommended clock frequency to 20 MHz will halve the response time to 49ms. Response time will become slower if the total duration of all bursts is greater than 33 ms, i.e. an average of 5.5 ms per channel[/code]...and the burst duration is to set by a cap.i did experimented with the QT160! but i cant touch 2 buttons at the same time!hehe... this is a special feature of the QT160 that's called AKS - Adjacent Key Supression, that's described on the first page of the datasheet:[code=QT160 Datasheet]The QT160 also offers the unique adjacent key suppression (AKS) which suppresses touch from weaker respnding keys and allows only a dominant key to detect, for example to solve the problem of large fingers on tightly spaced keys.So, that's the explanation, why only one input is working at a time!hmm... :-\ maybe you should invest some money in some single operated QT113's. The setup of the QT113 seems quite easy, see:The QT113's response time is highly dependent on burst length, which in turn is dependent on Cs and Cx. With increasing Cs, response time slows, while increasing levels of Cs reduce response time. Fig 4-3 shows the typical effects of Cs and Cx on response time.[/code]Best regards,Michael Quote Link to comment Share on other sites More sharing options...
Geerinckx Posted December 30, 2006 Author Report Share Posted December 30, 2006 EllowsI know, next time i buy such an expensive Ic i furst fully read all the specs!What did you pay for the QT113I payed 11€/IC so fot the 2: 22€GrtzzGert Quote Link to comment Share on other sites More sharing options...
SLP Posted December 30, 2006 Report Share Posted December 30, 2006 Why don't you just use tactile switches? Quote Link to comment Share on other sites More sharing options...
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