From: Chris E. <roo...@gm...> - 2006-10-31 07:28:09
|
Hello, I am trying to get gumstix/robostix i2c working. I have set up i2c, installed the i2c bootloader, and tried to send i2c-io.ehx to the robostix as follows: # i2c-load --reboot 0x0b write i2c-io.hex However, I receive the following errors: # i2c-load --reboot 0x0b write i2c-io.hex i2c: error: timeout i2c: msg_num: 2 msg_idx: 0 msg_ptr: 0 i2c: ICR: 000007e9 ISR: 00000004 i2c: log: ERROR: I2cTransfer: length is too big: 48 max: 20 ERROR: I2cTransfer: CRC failed: Rcvd: 0x00, expecting: 0x83 ERROR: I2cReadBlock failed ERROR: Unable to retrieve boot information from i2c address 0x0b And on subsequent tries: # i2c-load --reboot 0x0b write i2c-io.hex i2c_adapter i2c-0: i2c_pxa: timeout waiting for bus free i2c_adapter i2c-0: i2c_pxa: timeout waiting for bus free i2c_adapter i2c-0: i2c_pxa: timeout waiting for bus free i2c_adapter i2c-0: i2c_pxa: timeout waiting for bus free i2c_adapter i2c-0: i2c_pxa: timeout waiting for bus free i2c_adapter i2c-0: i2c_pxa: timeout waiting for bus free i2c: error: exhausted retries i2c: msg_num: 2 msg_idx: 0 msg_ptr: 0 i2c: ICR: 000007e9 ISR: 00000004 i2c: log: ERROR: I2cTransfer: ioctl failed: Remote I/O error (121) ERROR: I2cReadBlock failed ERROR: Unable to retrieve boot information from i2c address 0x0b Did I miss something? Is something configured incorrectly? When I boot the boards, the robostix LED flashes red as described on the wiki, so I assume I did everything right. |
From: Dave H. <dhy...@gm...> - 2006-10-31 08:53:44
|
Hi Chris, > I am trying to get gumstix/robostix i2c working. I have set up i2c, > installed the i2c bootloader, and tried to send i2c-io.ehx to the robostix > as follows: How fast is the LED flashing? It should be about twice per second if you've just programmed the bootloader. Did you program the fuses? You can use the pgm-fuse-bootloader from the robostix directory. How about: i2c-load 0x0b info Once you start getting errors, you may need to reboot the gumstix (or remove and reload the i2c modules). -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris E. <roo...@gm...> - 2006-10-31 23:04:37
|
Thanks for the response, Dave. The LED is flashing about twice per second. I believe I programmed the fuses correctly. # i2c-load 0x0b info ERROR: I2cTransfer: CRC failed: Rcvd: 0x00, expecting: 0xc5 ERROR: I2cReadBlock failed ERROR: Unable to retrieve boot information from i2c address 0x0b On 10/31/06, Dave Hylands <dhy...@gm...> wrote: > > Hi Chris, > > > I am trying to get gumstix/robostix i2c working. I have set up i2c, > > installed the i2c bootloader, and tried to send i2c-io.ehx to the > robostix > > as follows: > > How fast is the LED flashing? It should be about twice per second if > you've just programmed the bootloader. > > Did you program the fuses? > You can use the pgm-fuse-bootloader from the robostix directory. > > How about: > > i2c-load 0x0b info > > Once you start getting errors, you may need to reboot the gumstix (or > remove and reload the i2c modules). > > -- > Dave Hylands > Vancouver, BC, Canada > http://www.DaveHylands.com/ > > ------------------------------------------------------------------------- > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job > easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: Dave H. <dhy...@gm...> - 2006-11-01 03:58:10
|
Hi Chris, On 10/31/06, Chris Evans <roo...@gm...> wrote: > Thanks for the response, Dave. > > The LED is flashing about twice per second. > > I believe I programmed the fuses correctly. > > # i2c-load 0x0b info > ERROR: I2cTransfer: CRC failed: Rcvd: 0x00, expecting: 0xc5 > ERROR: I2cReadBlock failed > ERROR: Unable to retrieve boot information from i2c address 0x0b OK - I put together some code to test the i2c link. You can find some documentaiton over here: http://docwiki.gumstix.org/Robostix_i2c_test This will require you to switch back to using the standalone fuse settings, but it will at least help establish if the gumstix and robostix are connected together properly. -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris E. <roo...@gm...> - 2006-11-07 09:09:47
|
Hey Dave, I was finally able to try this out- it looks like something is wrong. Here is the output I get from i2c-test gumstix: SCL: 0 SDA: 1 robostix: SCLw: 1 SCLr: 0 SDAw: 1 SDAr: 1 DDRD: 0 PIND: 2 As you can see, its much different than what you have listed on the wiki page. Any ideas? On 10/31/06, Dave Hylands <dhy...@gm...> wrote: > > Hi Chris, > > On 10/31/06, Chris Evans <roo...@gm...> wrote: > > Thanks for the response, Dave. > > > > The LED is flashing about twice per second. > > > > I believe I programmed the fuses correctly. > > > > # i2c-load 0x0b info > > ERROR: I2cTransfer: CRC failed: Rcvd: 0x00, expecting: 0xc5 > > ERROR: I2cReadBlock failed > > ERROR: Unable to retrieve boot information from i2c address 0x0b > > OK - I put together some code to test the i2c link. You can find some > documentaiton over here: > http://docwiki.gumstix.org/Robostix_i2c_test > > This will require you to switch back to using the standalone fuse > settings, but it will at least help establish if the gumstix and > robostix are connected together properly. > > -- > Dave Hylands > Vancouver, BC, Canada > http://www.DaveHylands.com/ > > ------------------------------------------------------------------------- > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job > easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: Dave H. <dhy...@gm...> - 2006-11-07 14:47:57
|
Hi Chris, > I was finally able to try this out- it looks like something is wrong. Here > is the output I get from i2c-test > > gumstix: SCL: 0 SDA: 1 > robostix: SCLw: 1 SCLr: 0 SDAw: 1 SDAr: 1 DDRD: 0 PIND: 2 > > As you can see, its much different than what you have listed on the wiki > page. Any ideas? This often happens if the i2c driver is loaded, but if you're seeing with the i2c driver (i2c-pxa and i2c-dev) not being loaded, then it tells me that the SCL line is being held low (could be a solder-bridge). This would of course explain why i2c doesn't work. It could also be that the pullup resistor on the robostix isn't making connection. Try doing this: modprobe proc_gpio echo "GPIO out set" > /proc/gpio/GPIO81 and then press the spacebar while i2c-test is running. Do you see any changes? GPIO 81 is the NSSP_CLK pin, which is immediately adjacent to SCL on the hirose connector (SDA is next to it on the other side). Next thing to try is to take the SCL pin on the UARTS connector (pin 16) and verify that there is no connection with ground (using a multimeter). If it's not shorted to ground then you can try connecting it to pin 14, which is +5. Press the space bar while the i2c-test program is running. DO you see any change? -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Dave H. <dhy...@gm...> - 2006-11-07 14:52:47
|
Hi Chris, > Next thing to try is to take the SCL pin on the UARTS connector (pin > 16) and verify that there is no connection with ground (using a > multimeter). If it's not shorted to ground then you can try connecting > it to pin 14, which is +5. Press the space bar while the i2c-test > program is running. DO you see any change? Just a note - don't leave things connected this way for very long (i.e. try to do the test quickly). Watch the blue led for strange behaviour. I'm concerned that if you happen to short out +5 and ground something bad could happen. The regulator should just overheat and go into shutdown if shorted (which is why it's important to do the continuity test first). If you do happen to short Gnd and +5, the robostix would immediately stop working (which is why watching the Blue LED is important - it would go out). -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris E. <roo...@gm...> - 2006-11-07 22:53:52
|
Curioser and curioser... I thought that before I tried what you said I would remove the tweener board and see if somehow that was causing part of the problem. My normal setup is robotstix -> tweener -> gumstix -> wifistix. I plug 5v into the tweener and everything works. When I remove the tweener now, nothing will boot. The blue led on the robostix doesn't even flash (although all the green leds are lit) and the wifistix never comes online. I have tried: 5v into the wifistix 5v into the robostix 4v into the wifistix and 5v into the robostix Removing the wifistix and connecting 5v into the robostix causes the robostix to immediately go into reset. If I remove the robostix, the wifistix does come online. Is it possible my robostix is all kinds of defective? On 11/7/06, Dave Hylands <dhy...@gm...> wrote: > > Hi Chris, > > > Next thing to try is to take the SCL pin on the UARTS connector (pin > > 16) and verify that there is no connection with ground (using a > > multimeter). If it's not shorted to ground then you can try connecting > > it to pin 14, which is +5. Press the space bar while the i2c-test > > program is running. DO you see any change? > > Just a note - don't leave things connected this way for very long > (i.e. try to do the test quickly). Watch the blue led for strange > behaviour. I'm concerned that if you happen to short out +5 and ground > something bad could happen. The regulator should just overheat and go > into shutdown if shorted (which is why it's important to do the > continuity test first). > > If you do happen to short Gnd and +5, the robostix would immediately > stop working (which is why watching the Blue LED is important - it > would go out). > > -- > Dave Hylands > Vancouver, BC, Canada > http://www.DaveHylands.com/ > > ------------------------------------------------------------------------- > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job > easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > |
From: Dave H. <dhy...@gm...> - 2006-11-07 23:25:55
|
Hi Chris, On 11/7/06, Chris Evans <roo...@gm...> wrote: > Curioser and curioser... > > I thought that before I tried what you said I would remove the tweener board > and see if somehow that was causing part of the problem. My normal setup is > robotstix -> tweener -> gumstix -> wifistix. I plug 5v into the tweener and > everything works. When I remove the tweener now, nothing will boot. The blue > led on the robostix doesn't even flash (although all the green leds are lit) > and the wifistix never comes online. Whenever you use a robostix, you always need to at least provide power to the robostix. Normally, any of the power jacks is V_BATT and it doesn't matter which onw you plug into, since they're all connected up. Since the robostix will often be powered from batteries, and V_BATT can't exceed about 6v, the power jack on the robostix is called V_ROBOBATT, and it goes through a 5v regulator to become V_BATT. This allows a 9v battery to be used to power the robostix & gumstix. However, it means that if you plug power into say the tweener, then the gumstix will be properly powered, but the robostix will not. It will get partial power in the form of leakage current from lines connected to the gumstix. So: RULE 1: When using a robostix, make sure you plug the jack into the robostix. Also, the voltage regulator attached to the robostix can only provide 500ma, so some cards (like Wifi cards) don't work, because they try to draw too much current. When a robostix is plugged in and no tweener is used and no serial adapter is plugged into the gumstix jack, then you need to put a 10k resistor between 4 of the gumstix adapter and +5 from one of the UARTs pins. Some people have also had success putting the resistor beteen pins 3 & 4 of the gumstix connector. Failing to install the resistor will cause the boot to think that the user is causing a Break and it will drop into u-boot. By default, the robostix is held in reset when booting. You can perform the modifications mentioned on this page to get the robostix to run as the gumstix is booting: http://docswiki.gumstix.org/Robostix_uboot So you'd need to perform more tests taking the above into consideration before being able to figure out if the robostix is good or bad. Ideally, you'd do the following steps: 1 - Connect a serial adapter to UART-0 on the robostix and boot it up all by itself. The robostix will report what it sees on the i2c bus. You can press keys to modify what it does. 2 - Plug in the tweener to the robostix and see if the behaviour changes 3 - Run the gumstix with the wifistix. ssh in and run the i2c-test program. This might not work if you have an older gumstix (since the older gumstix doesn't have a pullup on the FFUART-RxD line). 4 - Plug in the tweener to the gumstix and see what happens when running i2c-test -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: ken s. <ken...@gm...> - 2006-11-07 23:52:26
|
On 11/7/06, Dave Hylands <dhy...@gm...> wrote: > Hi Chris, > > On 11/7/06, Chris Evans <roo...@gm...> wrote: > > Curioser and curioser... > > > > I thought that before I tried what you said I would remove the tweener board > > and see if somehow that was causing part of the problem. My normal setup is > > robotstix -> tweener -> gumstix -> wifistix. I plug 5v into the tweener and > > everything works. When I remove the tweener now, nothing will boot. The blue > > led on the robostix doesn't even flash (although all the green leds are lit) > > and the wifistix never comes online. > > Whenever you use a robostix, you always need to at least provide power > to the robostix. Normally, any of the power jacks is V_BATT and it > doesn't matter which onw you plug into, since they're all connected > up. > > Since the robostix will often be powered from batteries, and V_BATT > can't exceed about 6v, the power jack on the robostix is called > V_ROBOBATT, and it goes through a 5v regulator to become V_BATT. This > allows a 9v battery to be used to power the robostix & gumstix. pictorial view... http://pubs.gumstix.org/documents/Powering_a_Gumstix.pdf |
From: Dave H. <dhy...@gm...> - 2006-11-08 01:20:54
|
Hi Ken, > > Since the robostix will often be powered from batteries, and V_BATT > > can't exceed about 6v, the power jack on the robostix is called > > V_ROBOBATT, and it goes through a 5v regulator to become V_BATT. This > > allows a 9v battery to be used to power the robostix & gumstix. > > pictorial view... > http://pubs.gumstix.org/documents/Powering_a_Gumstix.pdf Ahah. I see the spec has been changed to 6v now. It used to be higher.... -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chad R. <cr...@lu...> - 2006-11-08 01:27:48
|
What PCB house does Gumstix use? I've used a number of them and I'm not necessarily looking for input on which is 'best', just curious what Gumstix itself chose. Thanks, Chad |
From: ken s. <ken...@gm...> - 2006-11-08 02:01:34
|
On 11/7/06, Dave Hylands <dhy...@gm...> wrote: > Hi Ken, > > > > Since the robostix will often be powered from batteries, and V_BATT > > > can't exceed about 6v, the power jack on the robostix is called > > > V_ROBOBATT, and it goes through a 5v regulator to become V_BATT. This > > > allows a 9v battery to be used to power the robostix & gumstix. > > > > pictorial view... > > http://pubs.gumstix.org/documents/Powering_a_Gumstix.pdf > > Ahah. I see the spec has been changed to 6v now. It used to be higher.... I wouldn't call it a spec. 6v applied to V_BATT should be viewed as a maximum value. Damage will occur if V_BATT exceeds 6v. V_ROBOBATT maximum becomes a thermal issue that depends on the V_BATT load you present to the robostix... --- Ken |
From: Jesse W. <jes...@gm...> - 2006-11-08 07:37:35
|
So it's not good to power a robostix with a 7.2 lipo then? That's what I was planning to do but....no go? On 11/7/06, ken staton <ken...@gm...> wrote: > > On 11/7/06, Dave Hylands <dhy...@gm...> wrote: > > Hi Ken, > > > > > > Since the robostix will often be powered from batteries, and V_BATT > > > > can't exceed about 6v, the power jack on the robostix is called > > > > V_ROBOBATT, and it goes through a 5v regulator to become V_BATT. > This > > > > allows a 9v battery to be used to power the robostix & gumstix. > > > > > > pictorial view... > > > http://pubs.gumstix.org/documents/Powering_a_Gumstix.pdf > > > > Ahah. I see the spec has been changed to 6v now. It used to be > higher.... > > I wouldn't call it a spec. > 6v applied to V_BATT should be viewed as a maximum value. > Damage will occur if V_BATT exceeds 6v. > > V_ROBOBATT maximum becomes a thermal issue that > depends on the V_BATT load you present to the robostix... > > --- > Ken > > ------------------------------------------------------------------------- > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job > easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > _______________________________________________ > gumstix-users mailing list > gum...@li... > https://lists.sourceforge.net/lists/listinfo/gumstix-users > -- -Jesse W. |
From: Chris D. <cg...@co...> - 2006-11-08 15:19:07
|
On 11/8/06, Jesse Welling <jes...@gm...> wrote: > So it's not good to power a robostix with a 7.2 lipo then? > That's what I was planning to do but....no go? Jesse, The issue is a thermal one. Depending on the power load you're placing on the linear regulator on the robotstix (and, to a lesser degree, the ambient temperature), it may or may not overtemp and go into thermal shutdown. You shouldn't be able to break anything by forcing it into thermal shutdown, but it will cause the system to (at least) reset. best, -chris |
From: ken s. <ken...@gm...> - 2006-11-08 15:42:33
|
On 11/7/06, Jesse Welling <jes...@gm...> wrote: > So it's not good to power a robostix with a 7.2 lipo then? > That's what I was planning to do but....no go? The robostix regulators are Micrel 5219-5.0 in MSOP-8. You'll have to read the data sheet section "Thermal Considerations", starting on page 8. If you are just powering a robostix, its maximum input at V_ROBOBATT is 12v. If you have anything connected to V_BATT, you must consider the thermal limit of the regulator. Page 10 of the regulator data sheet has an example that shows: operating at room temperature with maximum continuous output current (500mA) requires an input voltage no higher than 5.68v. --- Ken > > > On 11/7/06, ken staton < ken...@gm...> wrote: > > > > On 11/7/06, Dave Hylands < dhy...@gm...> wrote: > > > Hi Ken, > > > > > > > > Since the robostix will often be powered from batteries, and V_BATT > > > > > can't exceed about 6v, the power jack on the robostix is called > > > > > V_ROBOBATT, and it goes through a 5v regulator to become V_BATT. > This > > > > > allows a 9v battery to be used to power the robostix & gumstix. > > > > > > > > pictorial view... > > > > > http://pubs.gumstix.org/documents/Powering_a_Gumstix.pdf > > > > > > Ahah. I see the spec has been changed to 6v now. It used to be > higher.... > > > > I wouldn't call it a spec. > > 6v applied to V_BATT should be viewed as a maximum value. > > Damage will occur if V_BATT exceeds 6v. > > > > V_ROBOBATT maximum becomes a thermal issue that > > depends on the V_BATT load you present to the robostix... > > > > --- > > Ken > > |
From: Chris E. <roo...@gm...> - 2006-11-08 17:58:24
|
Hey Dave, When a robostix is plugged in and no tweener is used and no serial > adapter is plugged into the gumstix jack, then you need to put a 10k > resistor between 4 of the gumstix adapter and +5 from one of the UARTs > pins. Some people have also had success putting the resistor beteen > pins 3 & 4 of the gumstix connector. > > Failing to install the resistor will cause the boot to think that the > user is causing a Break and it will drop into u-boot. > > By default, the robostix is held in reset when booting. You can > perform the modifications mentioned on this page to get the robostix > to run as the gumstix is booting: > http://docswiki.gumstix.org/Robostix_uboot > I thought you only needed to add the resistor if you had a pre J-fab robostix? I received mine about a month ago, so I assumed it was J-fab. I am looking at this page: http://docswiki.gumstix.org/Robostix_Mods#Pullup_Resistor Also, I have already performed the modifications to run the robostix when the gumstix boots. Everything seemed to function when I was using a tweener. |
From: Dave H. <dhy...@gm...> - 2006-11-08 18:49:15
|
Hi Chris, > I thought you only needed to add the resistor if you had a pre J-fab > robostix? I received mine about a month ago, so I assumed it was J-fab. I am > looking at this page: > http://docswiki.gumstix.org/Robostix_Mods#Pullup_Resistor Hmmm. I think that I'll have to revise that. With the robostix, the RxD on the gumstix conector is a 5v logic level line. It goes through a voltage converter to become 3.3v. The pullup on the post-J fab gumstix (note that the fab level is referring to the gumstix board and not the robostix board) is on this 3.3v RxD line. Since the voltage translator on the robostix will always be driving this, that particular resistor becomes irrelevant. What's important is that there be a resistor on the 5v RxD line, so that when no serial adapter is plugged in, it sits in the idle state. -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris E. <roo...@gm...> - 2006-11-09 09:27:16
|
Hey Dave, I managed to get everything booting without a tweener, and SCL is still being held low. Try doing this: > > modprobe proc_gpio > echo "GPIO out set" > /proc/gpio/GPIO81 > > and then press the spacebar while i2c-test is running. Do you see any > changes? GPIO 81 is the NSSP_CLK pin, which is immediately adjacent to > SCL on the hirose connector (SDA is next to it on the other side). > > Next thing to try is to take the SCL pin on the UARTS connector (pin > 16) and verify that there is no connection with ground (using a > multimeter). If it's not shorted to ground then you can try connecting > it to pin 14, which is +5. Press the space bar while the i2c-test > program is running. DO you see any change? > I tried setting GPIO 81, but I still get the same output from i2c-test. I don't have a multimeter readily available, so I'll post the rest of my results tomorrow evening. |
From: Dave H. <dhy...@gm...> - 2006-11-09 14:45:07
|
Hi Chris, On 11/9/06, Chris Evans <roo...@gm...> wrote: > Hey Dave, > > I managed to get everything booting without a tweener, and SCL is still > being held low. OK - so we know the tweener isn't causing any problems. > I tried setting GPIO 81, but I still get the same output from i2c-test. I > don't have a multimeter readily available, so I'll post the rest of my > results tomorrow evening. And there isn't a solderbridge between SCL and GPIO81. It feels like the pullup resistor might be missing. I thought of something else I can throw into i2c-test. -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris E. <roo...@gm...> - 2006-11-10 01:14:32
|
> > I tried setting GPIO 81, but I still get the same output from i2c-test. I > don't have a multimeter readily available, so I'll post the rest of my > results tomorrow evening. > Okay, I got ahold of a multimeter. There is no continuity between UARTS pins 15 (gnd) and 16 (SCL). So, I connected pins 14 and 16; here is the result of i2c-test: gumstix: SCL: 0 SDA: 1 robostix: SCLw: 1 SCLr: 1 SDAw: 1 SDAr: 1 DDRD: 0 PIND: 3 |
From: Dave H. <dhy...@gm...> - 2006-11-10 01:28:16
|
Hi Chris, > Okay, I got ahold of a multimeter. There is no continuity between UARTS pins > 15 (gnd) and 16 (SCL). So, I connected pins 14 and 16; here is the result of > i2c-test: > > gumstix: SCL: 0 SDA: 1 > robostix: SCLw: 1 SCLr: 1 SDAw: 1 SDAr: 1 DDRD: 0 PIND: 3 So connecting pins 14 & 16 should have forced SCL high (which the robostix is reporting), but the gumstix is still seeing a 0. I'm assuming that if you connect 15 and 16, then the robostix will report SCLr: 0 That tell me its not the pullup resistor, but something with the hirose conenctor or the voltage conversion circuitry, or something on the gumstix itself. Do you have any other daughtercards? We could try connecting the SCL line on a breakout-gs or a waysmall to 3.3v and see if the i2c-test program on the gumstix detects it. -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris E. <roo...@gm...> - 2006-11-10 03:20:33
|
> I'm assuming that if you connect 15 and 16, then the robostix will > report SCLr: 0 Confirmed. Do you have any other daughtercards? We could try connecting the SCL > line on a breakout-gs or a waysmall to 3.3v and see if the i2c-test > program on the gumstix detects it. Unfortunately this is all I've got. What are my options are this point? |
From: Dave H. <dhy...@gm...> - 2006-11-10 04:54:59
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Hi Chris, > Unfortunately this is all I've got. What are my options are this point? Well it seems to be a hardware problem of some sort. I put photo of the gumstix board over here: http://www.davehylands.com/gumstix-wiki/i2c/connex-top.jpg I've identified the LTC1633 chip, which sits on the i2c bus. I've also labelled the various pins. Another test you could do is to try is to verify no connectivity between SCL and Gnd (with power off), and if that's the case (no connectivity) try connecting SCL to Vcc while i2ctest is running on the gumstix. You should see the: gumstix: SCL: 1 SDA: 1 If you don't then the problem is on the gumstix board. I also put up this photo: http://www.davehylands.com/gumstix-wiki/i2c/Tweener-i2c.jpg that identifies the i2c stuff on the tweener. Again, check that no continuity exists between Gnd and SCL. Then try connecting SCL to Vcc with i2c-test running. On my gumstix, it comes up like: gumstix: SCL: 0 SDA: 1 and touching SCL to Vcc changes the SCL to 1. if that's the case on yours, then you know that the gumstix side of thinngs is fine. Actually if you perform this second test first and it passes, then there's no need to do te first test mentioned above. You can also repeat the test with just the tweener and robostix. This requires a serial adapter connected to UART-0 on the robostix. -- Dave Hylands Vancouver, BC, Canada http://www.DaveHylands.com/ |
From: Chris E. <roo...@gm...> - 2006-11-10 08:06:38
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Hey Dave, Another test you could do is to try is to verify no connectivity > between SCL and Gnd (with power off), and if that's the case (no > connectivity) try connecting SCL to Vcc while i2ctest is running on > the gumstix. You should see the: > > gumstix: SCL: 1 SDA: 1 > > If you don't then the problem is on the gumstix board. I'm getting the same output here. Again, check that no continuity exists between Gnd and SCL. Then try > connecting SCL to Vcc with i2c-test running. On my gumstix, it comes > up like: > > gumstix: SCL: 0 SDA: 1 > > and touching SCL to Vcc changes the SCL to 1. For this one, I used ONLY the connex and tweener boards. When I first ran i2c-test, I saw: gumstix: SCL: 1 SDA: 1 And connecting SCL to Vcc didn't change that. |