From: Dominic . W. <dw...@ca...> - 2005-03-22 00:05:56
|
Hello, I was wondering if anyone else has had any successful experience with putting other more fault-tolerant (than VFAT) filesystems on the MMC? I am trying to use IBM's JFS with the gumstix. On another (i386) linux box, I can create the file-system, and I can compile a kernel for gumstix that has JFS support, and it mounts OK on gumstix. However, if the file system is marked as dirty, then the JFS kernel driver will not mount it until fsck.jfs has been run to check file system integrity and reset the dirty flag. My problem at the moment is cross-compiling the jfsutils tools which contains fsck.jfs - it seems to depend on a UUID library present in the e2fsprogs package, and I'm running into difficulty compiling that. If this doesn't work, then I may try others (e.g. ReiserFS, xfs). The goal is to have the MMC card not become corrupted in the event of an unforseen poweroff. Cheers, Dominic Wong Card Access Services |
From: 8923028 <is...@ci...> - 2005-08-28 11:16:52
|
After Tweener Modify. my gumstix do notwork with my minicom. i check the cut line with my electric meter, i thought i did not make any wrong while modify my tweener. The mincom message is show bellow. **** Welcome to gumstix! ***** U-Boot 1.0.0 (Jul 6 2004 - 20:50:37) U-Boot code: A3F00000 -> A3F18174 BSS space: -> A3F4984C DRAM Configuration: Bank #0: a0000000 64 MB Flash: 4 MB In: serial Out: serial Err: serial Hit any key to stop autoboot: 0 GUM> |
From: Dave H. <dhy...@gm...> - 2005-08-28 17:52:08
|
> After Tweener Modify. > my gumstix do notwork with my minicom. > i check the cut line with my electric meter, i thought i did not make any > wrong while modify my tweener. Which mod? Did you cut at the left red line or the right red line? What daughtercard (if any) are you using? It's dropping you into u-boot. --=20 Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Cyril B. <cyr...@gm...> - 2005-08-29 20:22:07
|
Did you hit any kay when the gumstix say "Hit any key to stop autoboot:"? If yes, you should not do that if you want to boot the linux.;-) Cyril On 8/28/05, 8923028 <is...@ci...> wrote: >=20 >=20 > After Tweener Modify. > my gumstix do notwork with my minicom. > i check the cut line with my electric meter, i thought i did not make any > wrong while modify my tweener. > The mincom message is show bellow. >=20 >=20 > **** Welcome to gumstix! ***** >=20 > U-Boot 1.0.0 (Jul 6 2004 - 20:50:37) >=20 > U-Boot code: A3F00000 -> A3F18174 > BSS space: -> A3F4984C > DRAM Configuration: > Bank #0: a0000000 64 MB > Flash: 4 MB > In: serial > Out: serial > Err: serial > Hit any key to stop autoboot: 0 > GUM> >=20 >=20 > ------------------------------------------------------- > SF.Net email is Sponsored by the Better Software Conference & EXPO > September 19-22, 2005 * San Francisco, CA * Development Lifecycle=20 > Practices > Agile & Plan-Driven Development * Managing Projects & Teams * Testing & Q= A > Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: Alexandre P. N. <al...@om...> - 2005-08-29 20:32:10
|
Cyril Bazin escreveu: > Did you hit any kay when the gumstix say "Hit any key to stop autoboot:"? > If yes, you should not do that if you want to boot the linux.;-) > > Cyril > Take a look into a discussion happening in this mailing list (the subject was: gumstix+cfstix+robostix+tweener) I guess the guy had the same problem and solved it with a resistor, it's something related to a serial line flutuating, making u-boot "thinks"someone pressed a key. I hope it helps. Alexandre |
From: Byrom D. <by...@co...> - 2005-08-29 21:48:35
|
Hey, On Mon, Aug 29, 2005 at 05:32:01PM -0300, Alexandre Pereira Nunes wrote: > > Did you hit any key when the gumstix say "Hit any key to stop autoboot:"? > > [...] > > Cyril > > Take a look into a discussion happening in this mailing list (the > subject was: gumstix+cfstix+robostix+tweener) > > I guess the guy had the same problem and solved it with a resistor, it's > something related to a serial line flutuating, making u-boot > "thinks" someone pressed a key. That was me. Actually, my kit worked fine with the modified tweener. It was misbehaving when I was using robostix, but didn't have the modified tweener. A resistor solved the problem for me. It seems to me that this might also happen if you cut the wrong trace on the tweener, like if you cut at both red lines instead of just the trace at the "left" red line in the picture on the tweener modify page. In that case, you won't have a console and it might be floating. (I bet you want a console.) At the GUM> prompt, is the kit responsive to keystrokes? If not, then check which trace you cut. Byrom |
From: Craig H. <cr...@gu...> - 2005-08-29 20:49:42
|
On Aug 28, 2005, at 4:16 AM, 8923028 wrote: > U-Boot 1.0.0 (Jul 6 2004 - 20:50:37) Not sure what daughtercards you're working with, but this is a very old version of u-boot. You might want to upgrade. C |
From: <tho...@be...> - 2005-09-03 15:57:15
|
> > Hi, > > I've just done a fresh build of gumstix-buildroot and it has created > build_arm_nofpu, toolchain_build_arm_nofpu and root_arm_fs_nofpu etc. I'm > sure it's never created this nofpu business on previous builds. What is > the > meaning of the nofpu and why has it appeared now? I see ONLY the nofpu versions of build_arm, etc. Is this now normal? I cd'ed into build_arm_nofpu/linux2.6.9.11*gum and did a make menuconfig. Everything seemed ok after getting an ncurses package. I built using a --revsion 549 flag. Thanks, Dave Thomas |
From: Craig H. <cr...@gu...> - 2005-09-03 21:44:08
|
On Sep 3, 2005, at 8:57 AM, <tho...@be...> <tho...@be...> wrote: >> >> Hi, >> >> I've just done a fresh build of gumstix-buildroot and it has created >> build_arm_nofpu, toolchain_build_arm_nofpu and root_arm_fs_nofpu >> etc. I'm >> sure it's never created this nofpu business on previous builds. >> What is >> the >> meaning of the nofpu and why has it appeared now? >> > > > I see ONLY the nofpu versions of build_arm, etc. Is this now > normal? I cd'ed into build_arm_nofpu/linux2.6.9.11*gum and did a > make menuconfig. Everything seemed ok after getting an ncurses > package. > > I built using a --revsion 549 flag. Yes, I switched to using softfloat in the buildroot by default a while back now. C |
From: grillot s. <seb...@gm...> - 2005-11-24 15:49:09
|
-- Regist. Linux User #344952 Experience is the name everyone gives to their mistakes. -- Oscar Wilde |
From: Woods, J. C <wo...@es...> - 2005-12-16 16:21:17
|
Anyone had any problems doing SCP I keep getting type 74 (connection lost) error messages when I try to send a file to the gumstick via bluetooth although weirdly I can open an ssh. Sftp gives the same error. |
From: Nelson R. Jr. <Nelson.Rosa.Jr@Dartmouth.EDU> - 2006-02-12 21:02:29
|
Hi, Sorry if I'm using bad list etiquette; I'm obviously a noob to this sort of stuff. my question is has the below issue with the i2c-pxa module tainting the kernel been fixed in the 2.6.15 kernel yet? Is there a workaround until then? I'm still learning kernel programming, but do the i2c modules need to be loaded in order for me to use my i2c dependent kernel module? It seems that the linker does everything for me, but those EXPORT_SYMBOL macros make me wonder if things are linked in when the module is loaded into the kernel or at compile time. Since what I'm doing is time sensitive I just reverted back to the 2.6.11 kernel. The following is an aside on what my project is...maybe you all could provide some comments or suggestions. I am currently writing a kernel module to read in images from a c3088 camera module (if this has already been done please let know). My thoughts were to read in the images from a set of gpio pins and use the ioctl interface to allow the user to modify the camera registers, which can be manipulated from the i2c bus. I'm aware of the voltage level difference but i think i've modified the board accordingly. i've been relying heavily on LDD 3rd ed. and Mr. Hylands code from robostix_drv.c as a guide. I'm a little confused as to how the new i2c_io stuff work on the 2.6.15 kernel w/o the i2c stuff working properly. is the i2c code running on the latest kernel? Thanks, NR ====================================> Hi Craig, It turns out that if I build i2c as a module then it won't load. I've tracked it down to the following: drivers/base/platform.c contains the following: EXPORT_SYMBOL_GPL(platform_driver_register); which means that only modules which have the GPL license can link against it. drivers/i2c/busses/i2c-pxa.c seems to be missing the appropriate MODULE_LICENSE directive to indicate that it's GPL. I discovered that i2c-pxa.c seems to be fixed in 2.6.16-rc2. It wasn't fixed in 2.6.15-rc7 I've attached a patch that fixes the i2c-pxa.c file, and it seems to make things work. I also added it to the end of the series file. -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Nelson R. Jr. <Nelson.Rosa.Jr@Dartmouth.EDU> - 2006-02-12 21:08:02
|
forgot to add a subject to the first email... On Sun, 2006-02-12 at 16:02, Nelson Rosa Jr. wrote: > Hi, > > Sorry if I'm using bad list etiquette; I'm obviously a noob to this sort of stuff. > > my question is has the below issue with the i2c-pxa module tainting the kernel been fixed in the > 2.6.15 kernel yet? > > Is there a workaround until then? I'm still learning kernel programming, but do the i2c modules > need to be loaded in order for me to use my i2c dependent kernel module? > It seems that the linker does everything for me, but those EXPORT_SYMBOL macros make me wonder if > things are linked in when the module is loaded into the kernel or at compile time. > > Since what I'm doing is time sensitive I just reverted back to the 2.6.11 kernel. > > The following is an aside on what my project is...maybe you all could provide some comments > or suggestions. I am currently writing a kernel module to read in images from a c3088 > camera module (if this has already been done please let know). My thoughts were to read in the > images from a set of gpio pins and use the ioctl interface to allow the user to modify the camera > registers, which can be manipulated from the i2c bus. > > I'm aware of the voltage level difference but i think i've modified the board accordingly. > > i've been relying heavily on LDD 3rd ed. and Mr. Hylands code from robostix_drv.c as a guide. > I'm a little confused as to how the new i2c_io stuff work on the 2.6.15 kernel w/o the > i2c stuff working properly. is the i2c code running on the latest kernel? > > Thanks, > NR > > > ====================================> > > Hi Craig, > > It turns out that if I build i2c as a module then it won't load. > > I've tracked it down to the following: > > drivers/base/platform.c contains the following: > EXPORT_SYMBOL_GPL(platform_driver_register); > > which means that only modules which have the GPL license can link against it. > > drivers/i2c/busses/i2c-pxa.c seems to be missing the appropriate > MODULE_LICENSE directive to indicate that it's GPL. > > I discovered that i2c-pxa.c seems to be fixed in 2.6.16-rc2. It wasn't > fixed in 2.6.15-rc7 > > I've attached a patch that fixes the i2c-pxa.c file, and it seems to > make things work. > I also added it to the end of the series file. > > -- > Dave Hylands > Vancouver, BC, Canada > http://www.DaveHylands.com/ |
From: George F. <cha...@gm...> - 2006-02-12 22:04:21
|
My mistake, yes, it is working, though I had to add the modules to /etc/mod= ules. George. |
From: Nelson R. Jr. <Nelson.Rosa.Jr@Dartmouth.EDU> - 2006-02-12 22:11:58
|
Hi George, Thanks for responding! I definitely need to reevaluate how I'm going to get video data into the gumstix. How long did it take you to get the DMA transfer working? And I'll trying modifying the /etc/modules file when i get some free time. On Sun, 2006-02-12 at 16:18, George Francis wrote: > Hi Nelson, > > I'm also having trouble with I2C in 2.6.15 at the moment, I'm trying > Dave's patch right now. > > On the C3088 front, no, sorry, I don't think you can use the GPIO's to > read in video. Raw video is a huge amount of information, the gpio's > will be far too slow for it. I've recently got raw video into a > gumstix from a VS6502 camera module, I resorted to a fast FIFO buffer > on the 92-pin bus on a connex to do it (data transfer via DMA). (a few > pics from it are on here: > http://www.gt-electronics.freeserve.co.uk/temp/ ) > > Bye for now, > > George. > > > ------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. Do you grep through log files > for problems? Stop! Download the new AJAX search engine that makes > searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! > http://sel.as-us.falkag.net/sel?cmd=lnk&kid3432&bid#0486&dat1642 > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users |
From: George F. <cha...@gm...> - 2006-02-12 22:15:23
|
>... How long did it take you to get the > DMA transfer working? about a month :( George. |
From: George F. <cha...@gm...> - 2006-02-12 21:18:49
|
Hi Nelson, I'm also having trouble with I2C in 2.6.15 at the moment, I'm trying Dave's patch right now. On the C3088 front, no, sorry, I don't think you can use the GPIO's to read in video. Raw video is a huge amount of information, the gpio's will be far too slow for it. I've recently got raw video into a gumstix from a VS6502 camera module, I resorted to a fast FIFO buffer on the 92-pin bus on a connex to do it (data transfer via DMA). (a few pics from it are on here: http://www.gt-electronics.freeserve.co.uk/temp/ ) Bye for now, George. |
From: Brian G. <gerkey@AI.SRI.COM> - 2006-02-16 01:41:59
|
For an application I'm working on (the Player robot server), I need full XDR support, including xdr_float() and xdr_double(). To make this work, I had to add the following line to sources/uClibc.config: UCLIBC_HAS_FULL_RPC=y With this change, everything builds and runs fine. Is there a reason that it is not set in SVN? brian. -- Brian P. Gerkey ge...@ai... SRI AI Center http://www.ai.sri.com/~gerkey |
From: Craig H. <cr...@gu...> - 2006-02-16 02:10:47
|
On Feb 15, 2006, at 5:42 PM, Brian Gerkey wrote: > For an application I'm working on (the Player robot server), I need > full XDR support, including xdr_float() and xdr_double(). To make > this work, I had to add the following line to sources/uClibc.config: > > UCLIBC_HAS_FULL_RPC=y > > With this change, everything builds and runs fine. Is there a > reason that it is not set in SVN? There are lots of options which are turned off by default, since most people don't need them, and they consume precious flash space. C |
From: Chris S. <chr...@gm...> - 2006-04-10 02:18:00
|
Dave and company I'm trying to get 3 PWMs working from the gumstix on the robostix. I've got two, but the Atmel PWM controller is a nightmare. This is what I have so far for 1A and 3C. All of the PWM pins are output enabled. But the Atmel timers are all intertwined. They are wierd. I just want another square wave at about 1000Hz. Anything simple that I'm missing? Chris int tccr1a =3D (1 << COM1A1) | (0 << COM1A0) // ChanA, non-inverting PWM, 244.14 Hz | (0 << WGM13) | (0 << WGM12) | (0 << WGM11) | (1 << WGM10); // PWM, Phase Correct, 10-b= it; int tccr1b =3D (0 << WGM13) | (1 << WGM12) | (1 << CS22) | (0 << CS21) | (0 << CS20); // prescale =3D = 64 int tccr3a =3D (1 << COM3C1) | (0 << COM3C0) // ChanC, non-inverting PWM, 976.5625 Hz | (0 << WGM33) | (0 << WGM32) | (0 << WGM31) | (1 << WGM30); // PWM, Phase Correct, 10-b= it int tccr3b =3D (0 << WGM33) | (1 << WGM32) | (0 << CS22) | (1 << CS21) | (1 << CS20); // prescale =3D = 8 int8_t tt; // Init Timer 1 for Steering PWM 1A WRITE_REG8(TCCR1A, tccr1a); WRITE_REG8(TCCR1B, tccr1b); WRITE_REG16(OCR1A, STEERING_MIDDLE); // Init Timer 3 for Motor PWM 3C WRITE_REG8(TCCR3A, tccr3a); WRITE_REG8(TCCR3B, tccr3b); WRITE_REG16(OCR3C, SPEED_OFF); |
From: Dave H. <dhy...@gm...> - 2006-04-10 02:51:21
|
Hi Chris, On 4/9/06, Chris Sears <chr...@gm...> wrote: > Dave and company > > I'm trying to get 3 PWMs working from the gumstix on the robostix. > I've got two, but the Atmel PWM controller is a nightmare. > > This is what I have so far for 1A and 3C. > All of the PWM pins are output enabled. > > But the Atmel timers are all intertwined. They are wierd. > I just want another square wave at about 1000Hz. > Anything simple that I'm missing? First of all, it helps to keep the following in mind: 1 - The timers are all completely independant and aren't intertwined at all= . 2 - The two 16 bit timers (Timer 1 and Timer 3) each have 3 potential outputs, which are designated A, B, and C. So each timer can run at some fundamental frequency. The various outputs can be used to change the duty cycle, but not the frequency. So OCR1A, OCR1B, and OCR1C must all run at the same frequency, but can all different duty cycles. The same for Timer3. Timers 0 and 2 are both 8-bit, and both only have one output compare each. So before I look at what you've done, I'd like to clarify what exactly you want to do. Which timer are you trying to get to run at 1 kHz? Whenever you're trying to get a very specific frequency out, you should probably pick on of the WGM modes which uses the ICRx register for the TOP. Varying ICRx varies the frequency. For PWM, you use the OCRxy registers to control the duty cycle. So the basic procedure I go through when trying to get a particular output is to 1 - Figure out which prescalar gets me in the rough ballpark 2 - Pick an appropriate WGM mode. 3 - Pick an approprate COM behaviour 4 - Determine the value of OCR which give you the appropriate duty cycles. -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris S. <chr...@gm...> - 2006-04-10 03:04:38
|
Dave I have one PWM (1A) for a servo at 240 Hz with a variable duty cycle. I have one PWM (3C) for a motor a 1KHz with a variable duty cycle. These = work. And I would like another PWM for a sampling unit also at about a 1KHz but with a square wave. Alternately, this could be any fixed duty cycle. It doesn't have to be perfectly square. These frequencies are approximate. The only requirement is that I know the sampling frequency when I'm done. thanks, Chris On 4/9/06, Dave Hylands <dhy...@gm...> wrote: > Hi Chris, > > On 4/9/06, Chris Sears <chr...@gm...> wrote: > > Dave and company > > > > I'm trying to get 3 PWMs working from the gumstix on the robostix. > > I've got two, but the Atmel PWM controller is a nightmare. > > > > This is what I have so far for 1A and 3C. > > All of the PWM pins are output enabled. > > > > But the Atmel timers are all intertwined. They are wierd. > > I just want another square wave at about 1000Hz. > > Anything simple that I'm missing? > > First of all, it helps to keep the following in mind: > > 1 - The timers are all completely independant and aren't intertwined at a= ll. > 2 - The two 16 bit timers (Timer 1 and Timer 3) each have 3 potential > outputs, which are designated A, B, and C. > > So each timer can run at some fundamental frequency. The various > outputs can be used to change the duty cycle, but not the frequency. > So OCR1A, OCR1B, and OCR1C must all run at the same frequency, but can > all different duty cycles. > > The same for Timer3. > > Timers 0 and 2 are both 8-bit, and both only have one output compare each= . > > So before I look at what you've done, I'd like to clarify what exactly > you want to do. > > Which timer are you trying to get to run at 1 kHz? Whenever you're > trying to get a very specific frequency out, you should probably pick > on of the WGM modes which uses the ICRx register for the TOP. Varying > ICRx varies the frequency. > > For PWM, you use the OCRxy registers to control the duty cycle. > > So the basic procedure I go through when trying to get a particular > output is to > > 1 - Figure out which prescalar gets me in the rough ballpark > 2 - Pick an appropriate WGM mode. > 3 - Pick an approprate COM behaviour > 4 - Determine the value of OCR which give you the appropriate duty cycles= . > > -- > Dave Hylands > Vancouver, BC, Canada > http://www.DaveHylands.com/ > > > ------------------------------------------------------- > This SF.Net email is sponsored by xPML, a groundbreaking scripting langua= ge > that extends applications into web and mobile media. Attend the live webc= ast > and join the prime developer group breaking into this new coding territor= y! > http://sel.as-us.falkag.net/sel?cmdlnk&kid=110944&bid$1720&dat=121642 > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: Dave H. <dhy...@gm...> - 2006-04-10 03:35:06
|
Hi Chris, > I have one PWM (1A) for a servo at 240 Hz with a variable duty cycle. > I have one PWM (3C) for a motor a 1KHz with a variable duty cycle. Thes= e work. > > And I would like another PWM for a sampling unit also at about a 1KHz > but with a square wave. Alternately, this could be any fixed duty > cycle. It doesn't have to be perfectly square. > > These frequencies are approximate. The only requirement is that I know > the sampling frequency when I'm done. So you can either setup Timer 2, or you could just use OCR3A or OCR3B since you've already got timer 3 running close to 1 kHz. Pick the OCR value to give you 50% duty cycle and you've got your square wave. For timer 2, you can use a divide by 64 prescalar, then you wind up with 250,000 ticks/second. Use CTC mode and set OCR2 to 125, and COM to toggle and you get exaclty 1 kHz (you need to toggle at 2kHz to get a 1kHz square wave). -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris S. <chr...@gm...> - 2006-04-10 04:39:05
|
Dave Since all I want is a 1KHz rising edge, I'm trying to duplicate the 3C 1KHz timer onto 3A or 3B. You would think it would just be something like: WRITE_REG(OCR3A, 128); WRITE_REG(OCR3B, 128); WRITE_REG(OCR3C, SPEED_OFF); I get a nice PWM on E5, but I still get no signal on pins E3 and E4. All of the PWM pins are output enabled. int tccr1a =3D (1 << COM1A1) | (0 << COM1A0) // ChanA, non-invertin= g PWM | (0 << WGM13) | (0 << WGM12) | (0 << WGM11) | (1 << WGM10); // PWM, Phase Correct, 10-b= it; int tccr1b =3D (0 << WGM13) | (1 << WGM12) | (1 << CS22) | (0 << CS21) | (0 << CS20); // prescale =3D = 64 int tccr3a =3D (1 << COM3C1) | (0 << COM3C0) // ChanC, non-invertin= g PWM | (0 << WGM33) | (0 << WGM32) | (0 << WGM31) | (1 << WGM30); // PWM, Phase Correct, 10-b= it int tccr3b =3D (0 << WGM33) | (1 << WGM32) | (0 << CS22) | (1 << CS21) | (1 << CS20); // prescale =3D = 8 int8_t tt; // Set all of the PWM pins as outputs READ_REG8(DDRB, &tt); // PWM 1A is B.5 WRITE_REG8(DDRB, tt | (1 << 5) | (1 << 6) | (1 << 7)); READ_REG8(PORTB, &tt); WRITE_REG8(PORTB, tt | (1 << 5) | (1 << 6) | (1 << 7)); READ_REG8(DDRE, &tt); // PWM 3A is E.3 WRITE_REG8(DDRE, tt | (1 << 3) | (1 << 4) | (1 << 5)); READ_REG8(PORTE, &tt); WRITE_REG8(PORTE, tt | (1 << 3) | (1 << 4) | (1 << 5) ); // Init Timer 1 for Steering PWM 1A WRITE_REG8(TCCR1A, tccr1a); WRITE_REG8(TCCR1B, tccr1b); WRITE_REG16(OCR1A, STEERING_MIDDLE); WRITE_REG16(OCR1B, 128); WRITE_REG16(OCR1C, 128); // Init Timer 3 for Motor PWM 3C WRITE_REG8(TCCR3A, tccr3a); WRITE_REG8(TCCR3B, tccr3b); WRITE_REG16(OCR3A, 40); WRITE_REG16(OCR3B, 40); WRITE_REG16(OCR3C, 40); On 4/9/06, Dave Hylands <dhy...@gm...> wrote: > Hi Chris, > > > I have one PWM (1A) for a servo at 240 Hz with a variable duty cycle. > > I have one PWM (3C) for a motor a 1KHz with a variable duty cycle. Th= ese work. > > > > And I would like another PWM for a sampling unit also at about a 1KHz > > but with a square wave. Alternately, this could be any fixed duty > > cycle. It doesn't have to be perfectly square. > > > > These frequencies are approximate. The only requirement is that I know > > the sampling frequency when I'm done. > > So you can either setup Timer 2, or you could just use OCR3A or OCR3B > since you've already got timer 3 running close to 1 kHz. Pick the OCR > value to give you 50% duty cycle and you've got your square wave. > > For timer 2, you can use a divide by 64 prescalar, then you wind up > with 250,000 ticks/second. Use CTC mode and set OCR2 to 125, and COM > to toggle and you get exaclty 1 kHz (you need to toggle at 2kHz to get > a 1kHz square wave). > > -- > Dave Hylands > Vancouver, BC, Canada > http://www.DaveHylands.com/ > > > ------------------------------------------------------- > This SF.Net email is sponsored by xPML, a groundbreaking scripting langua= ge > that extends applications into web and mobile media. Attend the live webc= ast > and join the prime developer group breaking into this new coding territor= y! > http://sel.as-us.falkag.net/sel?cmdlnk&kid=110944&bid$1720&dat=121642 > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: Dave H. <dhy...@gm...> - 2006-04-10 05:18:10
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Hi Chris, On 4/9/06, Chris Sears <chr...@gm...> wrote: > Dave > > Since all I want is a 1KHz rising edge, > I'm trying to duplicate the 3C 1KHz timer onto 3A or 3B. > You would think it would just be something like: > > WRITE_REG(OCR3A, 128); > WRITE_REG(OCR3B, 128); > WRITE_REG(OCR3C, SPEED_OFF); > > I get a nice PWM on E5, but I still get no signal on pins E3 and E4. > All of the PWM pins are output enabled. > > int tccr1a =3D (1 << COM1A1) | (0 << COM1A0) // ChanA, non-invert= ing PWM > | (0 << WGM13) | (0 << WGM12) > | (0 << WGM11) | (1 << WGM10); // PWM, Phase Correct, 10= -bit; > int tccr1b =3D (0 << WGM13) | (1 << WGM12) > | (1 << CS22) | (0 << CS21) | (0 << CS20); // prescale = =3D 64 > > int tccr3a =3D (1 << COM3C1) | (0 << COM3C0) // ChanC, non-invert= ing PWM > | (0 << WGM33) | (0 << WGM32) > | (0 << WGM31) | (1 << WGM30); // PWM, Phase Correct, 10= -bit > int tccr3b =3D (0 << WGM33) | (1 << WGM32) > | (0 << CS22) | (1 << CS21) | (1 << CS20); // prescale = =3D 8 I found the problem. You're only setting COM1A and COM3C. The others are set to zero, which means off. Question: why the READ_REG & WRITE_REG macros (I'm just curious, perhaps it's so you can add debugging?) -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |