From: Rizal N. <joe...@gm...> - 2009-04-03 18:00:38
|
Hi, I'm a newbie on working with gumstix and GPIO. I was wondering if anybody can point me to the right direction. I have a Verdex Pro with a 24-pin breakout board that let me access some signal lines and GPIO. I'm trying to use one of the GPIO lines as a output for a relay switch. I'm trying to use GPIO(0). I've tried to set the line to a high.So what i did was.. pxaregs GPLR0_0 1 #level is 1 pxaregs GPDR0_0 1 #direction as output but there is nothing going on the pin on GPIO0, I'm pretty sure im not doing things right here. In fact, I have no idea what im doing. I'm not sure what level means too. Hope someone can help me out or point me to the right direction. Thank you in advance.....for any help.... -- Joey aka. Rizal Home is where people think of you... |
From: Rizal N. <joe...@gm...> - 2009-04-03 19:27:23
|
Answering my question. Check if the connections are correct first. simple echo "GPIO out set" should bring it to a high Vbatt should be about 5volts On Fri, Apr 3, 2009 at 2:00 PM, Rizal Nor <joe...@gm...> wrote: > Hi, > > I'm a newbie on working with gumstix and GPIO. > I was wondering if anybody can point me to the right direction. > > I have a Verdex Pro with a 24-pin breakout board that let me access > some signal lines and GPIO. > I'm trying to use one of the GPIO lines as a output for a relay switch. > I'm trying to use GPIO(0). > > I've tried to set the line to a high.So what i did was.. > > pxaregs GPLR0_0 1 #level is 1 > pxaregs GPDR0_0 1 #direction as output > > but there is nothing going on the pin on GPIO0, I'm pretty sure im not > doing things right here. > In fact, I have no idea what im doing. I'm not sure what level means too. > Hope someone can help me out or point me to the right direction. > > Thank you in advance.....for any help.... > > > -- > Joey aka. Rizal > Home is where people think of you... > > -- Joey aka. Rizal Home is where people think of you... |
From: Dave H. <dhy...@gm...> - 2009-04-03 19:58:15
|
Hi, On Fri, Apr 3, 2009 at 12:27 PM, Rizal Nor <joe...@gm...> wrote: > Answering my question. > Check if the connections are correct first. > simple echo "GPIO out set" should bring it to a high > Vbatt should be about 5volts Yep - You should measure 3.3v on the GPIO line (that's the logic). You won't be able to drive a relay directly. You'll need to use the GPIO to drive a transistor or MOSFET, and have the transistor or MOSFET control the realy. Here are some examples: <http://www.dnatechindia.com/index.php/Tutorials/8051-Tutorial/Relay-Interfacing.html> <http://www.scienceprog.com/drive-relay-with-avr-microcontroller/> <http://www.mikroe.com/en/books/picbook/7_05chapter.htm> -- Dave Hylands Shuswap, BC, Canada http://www.DaveHylands.com/ |
From: Rizal N. <joe...@gm...> - 2009-04-03 20:35:39
|
Thanks Dave, I know i need a mosfet circuit to drive the relay. But what I'm not sure whether i need a relay in the first place. My device has a maximum load of 400ma. According to tutorial sites you gave me, the ULN2803 can drive up to 500ma. Should I still get a relay, or should i just drive it directly from the mosfet? On Fri, Apr 3, 2009 at 3:57 PM, Dave Hylands <dhy...@gm...> wrote: > Hi, > > On Fri, Apr 3, 2009 at 12:27 PM, Rizal Nor <joe...@gm...> > wrote: > > Answering my question. > > Check if the connections are correct first. > > simple echo "GPIO out set" should bring it to a high > > Vbatt should be about 5volts > > Yep - You should measure 3.3v on the GPIO line (that's the logic). You > won't be able to drive a relay directly. You'll need to use the GPIO > to drive a transistor or MOSFET, and have the transistor or MOSFET > control the realy. > > Here are some examples: > < > http://www.dnatechindia.com/index.php/Tutorials/8051-Tutorial/Relay-Interfacing.html > > > <http://www.scienceprog.com/drive-relay-with-avr-microcontroller/> > <http://www.mikroe.com/en/books/picbook/7_05chapter.htm> > > -- > Dave Hylands > Shuswap, BC, Canada > http://www.DaveHylands.com/ > > > ------------------------------------------------------------------------------ > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > -- Joey aka. Rizal Home is where people think of you... |
From: Dave H. <dhy...@gm...> - 2009-04-04 03:14:28
|
Hi Joey, > I know i need a mosfet circuit to drive the relay. But what I'm not sure > whether i need > a relay in the first place. My device has a maximum load of 400ma. According > to tutorial sites you gave me, the ULN2803 can drive up to 500ma. > Should I still get a relay, or should i just drive it directly from the > mosfet? It really depends on the type of thing that you're controlling. Is it inductive? or resistive? What voltage does your load require? Presumably your load needs DC rather than AC? -- Dave Hylands Shuswap, BC, Canada http://www.DaveHylands.com/ |
From: Rizal N. <joe...@gm...> - 2009-04-04 08:07:25
|
Hi Dave, Thank you for the quick reply again. On Fri, Apr 3, 2009 at 11:14 PM, Dave Hylands <dhy...@gm...> wrote: > Hi Joey, > > > I know i need a mosfet circuit to drive the relay. But what I'm not sure > > whether i need > > a relay in the first place. My device has a maximum load of 400ma. > According > > to tutorial sites you gave me, the ULN2803 can drive up to 500ma. > > Should I still get a relay, or should i just drive it directly from the > > mosfet? > > It really depends on the type of thing that you're controlling. Is it > inductive? or resistive? I want to control a satellite modem and a DO sensor. I'm not sure if its inductive or resistive. > What voltage does your load require? Presumably your load needs DC > rather than AC? The DO sensor is using 12 volts. And the satellite modem at 5 volts. As for now, the ULN2803 takes a while to get here. I'm going to use 2N4401 that i get from radioshack. It looks like this transistor can handle up to 600mA. I'm going to go for the relay switch option for now, unless you advise otherwise. Do you see any problems for using this transistor? > > -- > Dave Hylands > Shuswap, BC, Canada > http://www.DaveHylands.com/ > > > ------------------------------------------------------------------------------ > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > -- Joey aka. Rizal Home is where people think of you... |
From: William H. <wi...@ne...> - 2009-04-04 16:35:41
|
Hi Joey, please see my comment below. Rizal Nor wrote: > Hi Dave, > Thank you for the quick reply again. > > On Fri, Apr 3, 2009 at 11:14 PM, Dave Hylands <dhy...@gm... > <mailto:dhy...@gm...>> wrote: > > Hi Joey, > > > I know i need a mosfet circuit to drive the relay. But what I'm > not sure > > whether i need > > a relay in the first place. My device has a maximum load of > 400ma. According > > to tutorial sites you gave me, the ULN2803 can drive up to 500ma. > > Should I still get a relay, or should i just drive it directly > from the > > mosfet? > > It really depends on the type of thing that you're controlling. Is it > inductive? or resistive? > > > I want to control a satellite modem and a DO sensor. > I'm not sure if its inductive or resistive. > > > > What voltage does your load require? Presumably your load needs DC > rather than AC? > > > The DO sensor is using 12 volts. > And the satellite modem at 5 volts. > > As for now, the ULN2803 takes a while to get here. I'm going to use > 2N4401 that > i get from radioshack. It looks like this transistor can handle up to 600mA. > I'm going to go for the relay switch option for now, unless you advise > otherwise. > Do you see any problems for using this transistor? To assure good saturation, you need 40 mA of base current at Ic=400 mA. I doubt the Gumstix GPIO pin can supply this directly, and even if it could, it would not be good for it. I would use a MOSFET instead, but you need to either use a logic-level MOSFET or you can use the 2N4401 as an emitter-follower to provide approx. 12 V at the gate of the MOSFET. > > > > -- > Dave Hylands > Shuswap, BC, Canada > http://www.DaveHylands.com/ > > ------------------------------------------------------------------------------ > _______________________________________________ > gumstix-users mailing list > gum...@li... > <mailto:gum...@li...> > https://lists.sourceforge.net/lists/listinfo/gumstix-users > > > > > -- > Joey aka. Rizal > Home is where people think of you... > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------------ > > > ------------------------------------------------------------------------ > > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users |
From: Rizal N. <joe...@gm...> - 2009-04-04 19:34:16
|
Thanks William, Even half awake you can still give good advise:). My circuits knowledge is limited so let me see if I understand you correctly. As I understand the GPIO can drive a source at 3ma/10ma. This is not enough if I would like to have a transistor like 2N4401 reach full saturation. Which mean that I won't be able to amplify the current to drive something that requires 400mA. Am I correct. However, it should be enough for a relay wouldn't it? So you are recommending that I use a mosfet with a 2N4401in common-emitter inverted configuration so that i can achieve higher currents...right On Sat, Apr 4, 2009 at 12:39 PM, William Hue <wi...@ne...>wrote: > Please see clarification below. > > William Hue wrote: > > Hi Joey, please see my comment below. > > Rizal Nor wrote: > >> Hi Dave, > >> Thank you for the quick reply again. > >> > >> On Fri, Apr 3, 2009 at 11:14 PM, Dave Hylands <dhy...@gm... > >> <mailto:dhy...@gm...>> wrote: > >> > >> Hi Joey, > >> > >> > I know i need a mosfet circuit to drive the relay. But what I'm > >> not sure > >> > whether i need > >> > a relay in the first place. My device has a maximum load of > >> 400ma. According > >> > to tutorial sites you gave me, the ULN2803 can drive up to 500ma. > >> > Should I still get a relay, or should i just drive it directly > >> from the > >> > mosfet? > >> > >> It really depends on the type of thing that you're controlling. Is > it > >> inductive? or resistive? > >> > >> > >> I want to control a satellite modem and a DO sensor. > >> I'm not sure if its inductive or resistive. > >> > >> > >> > >> What voltage does your load require? Presumably your load needs DC > >> rather than AC? > >> > >> > >> The DO sensor is using 12 volts. > >> And the satellite modem at 5 volts. > >> > >> As for now, the ULN2803 takes a while to get here. I'm going to use > >> 2N4401 that > >> i get from radioshack. It looks like this transistor can handle up to > >> 600mA. > >> I'm going to go for the relay switch option for now, unless you advise > >> otherwise. > >> Do you see any problems for using this transistor? > > > > To assure good saturation, you need 40 mA of base current at Ic=400 mA. > > I doubt the Gumstix GPIO pin can supply this directly, and even if it > > could, it would not be good for it. I would use a MOSFET instead, but > > you need to either use a logic-level MOSFET or you can use the 2N4401 as > > an emitter-follower to provide approx. 12 V at the gate of the MOSFET. > > Sorry, I am still sleepy this morning. Emitter-follower configuration > would only provide GPIO voltage minus VBE. To provide more voltage at the > gate of the MOSFET, the 2N4401 must be in common-emitter inverting > configuration. Sorry about that. > > > > >> > >> > >> > >> -- > >> Dave Hylands > >> Shuswap, BC, Canada > >> http://www.DaveHylands.com/ > >> > >> > >> > ------------------------------------------------------------------------------ > >> > >> _______________________________________________ > >> gumstix-users mailing list > >> gum...@li... > >> <mailto:gum...@li...> > >> https://lists.sourceforge.net/lists/listinfo/gumstix-users > >> > >> > >> > >> > >> -- > >> Joey aka. Rizal > >> Home is where people think of you... > >> > >> > >> ------------------------------------------------------------------------ > >> > >> > ------------------------------------------------------------------------------ > >> > >> > >> > >> ------------------------------------------------------------------------ > >> > >> _______________________________________________ > >> gumstix-users mailing list > >> gum...@li... > >> https://lists.sourceforge.net/lists/listinfo/gumstix-users > > > > > ------------------------------------------------------------------------------ > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > -- Joey aka. Rizal Home is where people think of you... |
From: Dave H. <dhy...@gm...> - 2009-06-25 23:10:32
|
> Ive searched the list and gumstix.com and net but I still havnt bee able to > find a clear answer on: > > On the Audiostix GPIO what current does it supply and what is it rated for? > I have found the voltage that is suplied (3.3v) but cant find the current. The Audiostix uses a UCB1400 chip. The datasheet for the UCB1400, available from here: <http://www.nxp.com/acrobat_download/datasheets/UCB1400-02.pdf> says (on the bottom of page 50) that the max current (source or sink) is 2 mA. > To assure good saturation, you need 40 mA of base current at Ic=400 mA. I > doubt the Gumstix GPIO pin can supply this directly, and even if it could, > it would not be good for it. I would use a MOSFET instead, but you need to > either use a logic-level MOSFET or you can use the 2N4401 as an > emitter-follower to provide approx. 12 V at the gate of the MOSFET. None of the GPIO pins on the gumstix or any of the daughtercards that I'm aware of can provide 40 mA. You'd need to use an external buffer chip of some kind. -- Dave Hylands Shuswap, BC, Canada http://www.DaveHylands.com/ |
From: William H. <wi...@ne...> - 2009-04-04 16:39:29
|
Please see clarification below. William Hue wrote: > Hi Joey, please see my comment below. > Rizal Nor wrote: >> Hi Dave, >> Thank you for the quick reply again. >> >> On Fri, Apr 3, 2009 at 11:14 PM, Dave Hylands <dhy...@gm... >> <mailto:dhy...@gm...>> wrote: >> >> Hi Joey, >> >> > I know i need a mosfet circuit to drive the relay. But what I'm >> not sure >> > whether i need >> > a relay in the first place. My device has a maximum load of >> 400ma. According >> > to tutorial sites you gave me, the ULN2803 can drive up to 500ma. >> > Should I still get a relay, or should i just drive it directly >> from the >> > mosfet? >> >> It really depends on the type of thing that you're controlling. Is it >> inductive? or resistive? >> >> >> I want to control a satellite modem and a DO sensor. >> I'm not sure if its inductive or resistive. >> >> >> >> What voltage does your load require? Presumably your load needs DC >> rather than AC? >> >> >> The DO sensor is using 12 volts. >> And the satellite modem at 5 volts. >> >> As for now, the ULN2803 takes a while to get here. I'm going to use >> 2N4401 that >> i get from radioshack. It looks like this transistor can handle up to >> 600mA. >> I'm going to go for the relay switch option for now, unless you advise >> otherwise. >> Do you see any problems for using this transistor? > > To assure good saturation, you need 40 mA of base current at Ic=400 mA. > I doubt the Gumstix GPIO pin can supply this directly, and even if it > could, it would not be good for it. I would use a MOSFET instead, but > you need to either use a logic-level MOSFET or you can use the 2N4401 as > an emitter-follower to provide approx. 12 V at the gate of the MOSFET. Sorry, I am still sleepy this morning. Emitter-follower configuration would only provide GPIO voltage minus VBE. To provide more voltage at the gate of the MOSFET, the 2N4401 must be in common-emitter inverting configuration. Sorry about that. > >> >> >> >> -- >> Dave Hylands >> Shuswap, BC, Canada >> http://www.DaveHylands.com/ >> >> >> ------------------------------------------------------------------------------ >> >> _______________________________________________ >> gumstix-users mailing list >> gum...@li... >> <mailto:gum...@li...> >> https://lists.sourceforge.net/lists/listinfo/gumstix-users >> >> >> >> >> -- >> Joey aka. Rizal >> Home is where people think of you... >> >> >> ------------------------------------------------------------------------ >> >> ------------------------------------------------------------------------------ >> >> >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> gumstix-users mailing list >> gum...@li... >> https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: William H. <wi...@ne...> - 2009-04-05 03:04:51
|
Hi Joey, Yes. If you use a GPIO to drive the base of a transistor, and the transistor activates the relay, that would work. You need a base resistor to limit the current base current, and a reverse-biased diode across the relay coil to absorb the inductive voltage spike that occurs when the transistor turns off (or else the transistor will be damaged when you shut off the relay). Here are some example circuits: http://letsmakerobots.com/node/4285 The third circuit shown in that webpage actually shows what I meant about using the 2N4401 to get more voltage for the MOSFET's gate. William Rizal Nor wrote: > Thanks William, > > Even half awake you can still give good advise:). > My circuits knowledge is limited so let me see if I understand you > correctly. > As I understand the GPIO can drive a source at 3ma/10ma. This is not > enough if I would like to have a transistor like 2N4401 reach full > saturation. Which mean that I won't be able to amplify the current to > drive something that requires 400mA. Am I correct. However, it should be > enough for a relay wouldn't it? > > So you are recommending that I use a mosfet with a 2N4401in > common-emitter inverted configuration so that i can achieve higher > currents...right > > On Sat, Apr 4, 2009 at 12:39 PM, William Hue <wi...@ne... > <mailto:wi...@ne...>> wrote: > > Please see clarification below. > > William Hue wrote: > > Hi Joey, please see my comment below. > > Rizal Nor wrote: > >> Hi Dave, > >> Thank you for the quick reply again. > >> > >> On Fri, Apr 3, 2009 at 11:14 PM, Dave Hylands > <dhy...@gm... <mailto:dhy...@gm...> > >> <mailto:dhy...@gm... <mailto:dhy...@gm...>>> wrote: > >> > >> Hi Joey, > >> > >> > I know i need a mosfet circuit to drive the relay. But > what I'm > >> not sure > >> > whether i need > >> > a relay in the first place. My device has a maximum load of > >> 400ma. According > >> > to tutorial sites you gave me, the ULN2803 can drive up > to 500ma. > >> > Should I still get a relay, or should i just drive it > directly > >> from the > >> > mosfet? > >> > >> It really depends on the type of thing that you're > controlling. Is it > >> inductive? or resistive? > >> > >> > >> I want to control a satellite modem and a DO sensor. > >> I'm not sure if its inductive or resistive. > >> > >> > >> > >> What voltage does your load require? Presumably your load > needs DC > >> rather than AC? > >> > >> > >> The DO sensor is using 12 volts. > >> And the satellite modem at 5 volts. > >> > >> As for now, the ULN2803 takes a while to get here. I'm going to use > >> 2N4401 that > >> i get from radioshack. It looks like this transistor can handle > up to > >> 600mA. > >> I'm going to go for the relay switch option for now, unless you > advise > >> otherwise. > >> Do you see any problems for using this transistor? > > > > To assure good saturation, you need 40 mA of base current at > Ic=400 mA. > > I doubt the Gumstix GPIO pin can supply this directly, and even if it > > could, it would not be good for it. I would use a MOSFET > instead, but > > you need to either use a logic-level MOSFET or you can use the > 2N4401 as > > an emitter-follower to provide approx. 12 V at the gate of the > MOSFET. > > Sorry, I am still sleepy this morning. Emitter-follower > configuration would only provide GPIO voltage minus VBE. To provide > more voltage at the gate of the MOSFET, the 2N4401 must be in > common-emitter inverting configuration. Sorry about that. > > > > >> > >> > >> > >> -- > >> Dave Hylands > >> Shuswap, BC, Canada > >> http://www.DaveHylands.com/ > >> > >> > >> > ------------------------------------------------------------------------------ > >> > >> _______________________________________________ > >> gumstix-users mailing list > >> gum...@li... > <mailto:gum...@li...> > >> <mailto:gum...@li... > <mailto:gum...@li...>> > >> https://lists.sourceforge.net/lists/listinfo/gumstix-users > >> > >> > >> > >> > >> -- > >> Joey aka. Rizal > >> Home is where people think of you... > >> > >> > >> > ------------------------------------------------------------------------ > >> > >> > ------------------------------------------------------------------------------ > >> > >> > >> > >> > ------------------------------------------------------------------------ > >> > >> _______________________________________________ > >> gumstix-users mailing list > >> gum...@li... > <mailto:gum...@li...> > >> https://lists.sourceforge.net/lists/listinfo/gumstix-users > > > > ------------------------------------------------------------------------------ > _______________________________________________ > gumstix-users mailing list > gum...@li... > <mailto:gum...@li...> > https://lists.sourceforge.net/lists/listinfo/gumstix-users > > > > > -- > Joey aka. Rizal > Home is where people think of you... > > > ------------------------------------------------------------------------ > > ------------------------------------------------------------------------------ > > > ------------------------------------------------------------------------ > > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users |
From: Rizal N. <joe...@gm...> - 2009-04-05 05:04:26
|
Thanks William, I think I understand now. I tried wiring up the circuit too, and it works great. On Sat, Apr 4, 2009 at 9:38 PM, William Hue <wi...@ne...>wrote: > Hi Joey, > > Yes. If you use a GPIO to drive the base of a transistor, and the > transistor activates the relay, that would work. You need a base resistor > to limit the current base current, and a reverse-biased diode across the > relay coil to absorb the inductive voltage spike that occurs when the > transistor turns off (or else the transistor will be damaged when you shut > off the relay). Here are some example circuits: > > http://letsmakerobots.com/node/4285 > > The third circuit shown in that webpage actually shows what I meant about > using the 2N4401 to get more voltage for the MOSFET's gate. > > William > > > Rizal Nor wrote: > > Thanks William, > > > > Even half awake you can still give good advise:). > > My circuits knowledge is limited so let me see if I understand you > > correctly. > > As I understand the GPIO can drive a source at 3ma/10ma. This is not > > enough if I would like to have a transistor like 2N4401 reach full > > saturation. Which mean that I won't be able to amplify the current to > > drive something that requires 400mA. Am I correct. However, it should be > > enough for a relay wouldn't it? > > > > So you are recommending that I use a mosfet with a 2N4401in > > common-emitter inverted configuration so that i can achieve higher > > currents...right > > > > On Sat, Apr 4, 2009 at 12:39 PM, William Hue <wi...@ne... > > <mailto:wi...@ne...>> wrote: > > > > Please see clarification below. > > > > William Hue wrote: > > > Hi Joey, please see my comment below. > > > Rizal Nor wrote: > > >> Hi Dave, > > >> Thank you for the quick reply again. > > >> > > >> On Fri, Apr 3, 2009 at 11:14 PM, Dave Hylands > > <dhy...@gm... <mailto:dhy...@gm...> > > >> <mailto:dhy...@gm... <mailto:dhy...@gm...>>> wrote: > > >> > > >> Hi Joey, > > >> > > >> > I know i need a mosfet circuit to drive the relay. But > > what I'm > > >> not sure > > >> > whether i need > > >> > a relay in the first place. My device has a maximum load > of > > >> 400ma. According > > >> > to tutorial sites you gave me, the ULN2803 can drive up > > to 500ma. > > >> > Should I still get a relay, or should i just drive it > > directly > > >> from the > > >> > mosfet? > > >> > > >> It really depends on the type of thing that you're > > controlling. Is it > > >> inductive? or resistive? > > >> > > >> > > >> I want to control a satellite modem and a DO sensor. > > >> I'm not sure if its inductive or resistive. > > >> > > >> > > >> > > >> What voltage does your load require? Presumably your load > > needs DC > > >> rather than AC? > > >> > > >> > > >> The DO sensor is using 12 volts. > > >> And the satellite modem at 5 volts. > > >> > > >> As for now, the ULN2803 takes a while to get here. I'm going to > use > > >> 2N4401 that > > >> i get from radioshack. It looks like this transistor can handle > > up to > > >> 600mA. > > >> I'm going to go for the relay switch option for now, unless you > > advise > > >> otherwise. > > >> Do you see any problems for using this transistor? > > > > > > To assure good saturation, you need 40 mA of base current at > > Ic=400 mA. > > > I doubt the Gumstix GPIO pin can supply this directly, and even if > it > > > could, it would not be good for it. I would use a MOSFET > > instead, but > > > you need to either use a logic-level MOSFET or you can use the > > 2N4401 as > > > an emitter-follower to provide approx. 12 V at the gate of the > > MOSFET. > > > > Sorry, I am still sleepy this morning. Emitter-follower > > configuration would only provide GPIO voltage minus VBE. To provide > > more voltage at the gate of the MOSFET, the 2N4401 must be in > > common-emitter inverting configuration. Sorry about that. > > > > > > > >> > > >> > > >> > > >> -- > > >> Dave Hylands > > >> Shuswap, BC, Canada > > >> http://www.DaveHylands.com/ > > >> > > >> > > >> > > > ------------------------------------------------------------------------------ > > >> > > >> _______________________________________________ > > >> gumstix-users mailing list > > >> gum...@li... > > <mailto:gum...@li...> > > >> <mailto:gum...@li... > > <mailto:gum...@li...>> > > >> https://lists.sourceforge.net/lists/listinfo/gumstix-users > > >> > > >> > > >> > > >> > > >> -- > > >> Joey aka. Rizal > > >> Home is where people think of you... > > >> > > >> > > >> > > > ------------------------------------------------------------------------ > > >> > > >> > > > ------------------------------------------------------------------------------ > > >> > > >> > > >> > > >> > > > ------------------------------------------------------------------------ > > >> > > >> _______________________________________________ > > >> gumstix-users mailing list > > >> gum...@li... > > <mailto:gum...@li...> > > >> https://lists.sourceforge.net/lists/listinfo/gumstix-users > > > > > > > > ------------------------------------------------------------------------------ > > _______________________________________________ > > gumstix-users mailing list > > gum...@li... > > <mailto:gum...@li...> > > https://lists.sourceforge.net/lists/listinfo/gumstix-users > > > > > > > > > > -- > > Joey aka. Rizal > > Home is where people think of you... > > > > > > ------------------------------------------------------------------------ > > > > > ------------------------------------------------------------------------------ > > > > > > ------------------------------------------------------------------------ > > > > _______________________________________________ > > gumstix-users mailing list > > gum...@li... > > https://lists.sourceforge.net/lists/listinfo/gumstix-users > > > > ------------------------------------------------------------------------------ > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > -- Joey aka. Rizal Home is where people think of you... |
From: Donald S. <don...@ya...> - 2009-04-19 16:11:37
|
I'm planning a simple circuit off a GPIO line. I'll probably use a mosfet transistor to complete the circuit. What is the simplest way to vary the voltage on a given GPIO line? In the past I've done this over an RS232 port and used something like: /bin/dd if=/dev/zero of=/dev/ttyS2 That allowed me to vary the voltage from 0 to 12 (or something close to that) and use that with a mosfet to complete a circuit; Thats what I would like to do with the GPIO port. Thanks for any help, Donny in Tallahassee |
From: Donald S. <don...@ya...> - 2009-04-29 01:16:41
|
I have a Verdex pro XL6P and a GPS stix. Can anyone point me to a link that explains where on the circuit board the 4 GPIO ports are. A schematic? Anything? Am I the only one that has a hard time finding information on the wiki site? Thanks! Donny |
From: R. P. M. <log...@gm...> - 2009-04-29 01:45:05
|
Maybe this will have what you are looking for: http://pubs.gumstix.com/boards/ On 4/29/09, Donald Shrum <don...@ya...> wrote: > I have a Verdex pro XL6P and a GPS stix. Can anyone point me to a link that > explains where on the circuit board the 4 GPIO ports are. A schematic? > Anything? Am I the only one that has a hard time finding information on the > wiki site? > > Thanks! > > Donny > > > |
From: Rizal N. <joe...@gm...> - 2009-04-29 01:45:11
|
I don't know about the GPS stix, but some of the schematics are available at the link below. I think the GPS stix is there as well....you can check it out. http://pubs.gumstix.com/boards/ On Tue, Apr 28, 2009 at 9:16 PM, Donald Shrum <don...@ya...>wrote: > I have a Verdex pro XL6P and a GPS stix. Can anyone point me to a link > that explains where on the circuit board the 4 GPIO ports are. A > schematic? Anything? Am I the only one that has a hard time finding > information on the wiki site? > > > > Thanks! > > > > Donny > > > > > > > > ------------------------------------------------------------------------------ > Register Now & Save for Velocity, the Web Performance & Operations > Conference from O'Reilly Media. Velocity features a full day of > expert-led, hands-on workshops and two days of sessions from industry > leaders in dedicated Performance & Operations tracks. Use code vel09scf > and Save an extra 15% before 5/3. http://p.sf.net/sfu/velocityconf > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > > -- Joey aka. Rizal Home is where people think of you... |
From: Rizal N. <joe...@gm...> - 2009-04-29 01:48:16
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Oh yeah, if you click on the Audiostix, under readme, you can see that GPSstix uses version R791 under audiostix. "The original audiostix boards were built using PCB0006 (version R162) The revised audiostix (audiostix2) and the GPSstix use PCB00012 (version R791)" On Tue, Apr 28, 2009 at 9:41 PM, Rizal Nor <joe...@gm...> wrote: > I don't know about the GPS stix, but some of the schematics are available > at the link below. > I think the GPS stix is there as well....you can check it out. > > http://pubs.gumstix.com/boards/ > > On Tue, Apr 28, 2009 at 9:16 PM, Donald Shrum <don...@ya...>wrote: > >> I have a Verdex pro XL6P and a GPS stix. Can anyone point me to a link >> that explains where on the circuit board the 4 GPIO ports are. A >> schematic? Anything? Am I the only one that has a hard time finding >> information on the wiki site? >> >> >> >> Thanks! >> >> >> >> Donny >> >> >> >> >> >> >> >> ------------------------------------------------------------------------------ >> Register Now & Save for Velocity, the Web Performance & Operations >> Conference from O'Reilly Media. Velocity features a full day of >> expert-led, hands-on workshops and two days of sessions from industry >> leaders in dedicated Performance & Operations tracks. Use code vel09scf >> and Save an extra 15% before 5/3. http://p.sf.net/sfu/velocityconf >> _______________________________________________ >> gumstix-users mailing list >> gum...@li... >> https://lists.sourceforge.net/lists/listinfo/gumstix-users >> >> > > > -- > Joey aka. Rizal > Home is where people think of you... > > -- Joey aka. Rizal Home is where people think of you... |
From: kardon33 <Ad...@il...> - 2009-06-25 19:07:35
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Hi List, Ive searched the list and gumstix.com and net but I still havnt bee able to find a clear answer on: On the Audiostix GPIO what current does it supply and what is it rated for? I have found the voltage that is suplied (3.3v) but cant find the current. To assure good saturation, you need 40 mA of base current at Ic=400 mA. I doubt the Gumstix GPIO pin can supply this directly, and even if it could, it would not be good for it. I would use a MOSFET instead, but you need to either use a logic-level MOSFET or you can use the 2N4401 as an emitter-follower to provide approx. 12 V at the gate of the MOSFET. -- View this message in context: http://www.nabble.com/Learning-how-to-use-GPIO-tp22873709p24209342.html Sent from the Gumstix mailing list archive at Nabble.com. |
From: Adam M. <Ad...@il...> - 2009-06-29 18:00:36
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Also, when using the 10 GPIOs on the AudioStix, what do you connect the ground to? I suppose one of the grounds on the HWUART or STUART or is that completely wrong? Thanks -----Original Message----- From: Dave Hylands [mailto:dhy...@gm...] Sent: Thursday, June 25, 2009 7:10 PM To: General mailing list for gumstix users. Subject: Re: [Gumstix-users] Learning how to use GPIO > Ive searched the list and gumstix.com and net but I still havnt bee able to > find a clear answer on: > > On the Audiostix GPIO what current does it supply and what is it rated for? > I have found the voltage that is suplied (3.3v) but cant find the current. The Audiostix uses a UCB1400 chip. The datasheet for the UCB1400, available from here: <http://www.nxp.com/acrobat_download/datasheets/UCB1400-02.pdf> says (on the bottom of page 50) that the max current (source or sink) is 2 mA. > To assure good saturation, you need 40 mA of base current at Ic=400 mA. I > doubt the Gumstix GPIO pin can supply this directly, and even if it could, > it would not be good for it. I would use a MOSFET instead, but you need to > either use a logic-level MOSFET or you can use the 2N4401 as an > emitter-follower to provide approx. 12 V at the gate of the MOSFET. None of the GPIO pins on the gumstix or any of the daughtercards that I'm aware of can provide 40 mA. You'd need to use an external buffer chip of some kind. -- Dave Hylands Shuswap, BC, Canada http://www.DaveHylands.com/ ------------------------------------------------------------------------------ _______________________________________________ gumstix-users mailing list gum...@li... https://lists.sourceforge.net/lists/listinfo/gumstix-users |
From: Dave H. <dhy...@gm...> - 2009-06-29 18:44:15
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Hi Adam, On Mon, Jun 29, 2009 at 11:00 AM, Adam Magaluk<Ad...@il...> wrote: > Also, when using the 10 GPIOs on the AudioStix, what do you connect the ground to? You can use any of the ground signals. If you look at the schematics, you can see that GND is available on all 4 UART connectors, the I2C connector, the NSSP connector, and the PWM connector. > I suppose one of the grounds on the HWUART or STUART or is that completely wrong? They're all connected together through the ground plane. -- Dave Hylands Shuswap, BC, Canada http://www.DaveHylands.com/ |