[cc'ing dev list. This can be discussed in public]
On Wed, Sep 30, 2015 at 12:37 PM, Daniel Thompson daniel.thompson@linaro.org wrote:
Hi Grant
On 28/09/15 15:57, Grant Likely wrote:
On Mon, Sep 28, 2015 at 3:47 PM, Grant Likely grant.likely@linaro.org wrote:
Update on the Sensors board.
Unfortunately, some of the boards got shipped out without the Arduino bootloader installed on the Atmel. Before you can use the procedure in the starter guide, you'll need to disconnect the Sensors board from your 96boards baseboard and flash the bootloader. Pretty much any flashing method will work, but the easiest is probably to use another Arduino as a programmer as documented here (unless you already have an AVR-ISP programmer, in which case use that):
https://www.arduino.cc/en/Tutorial/ArduinoISP
I've also updated the getting started guide.
Sorry for the inconvenience. Let me know if you have any trouble flashing the bootloader.
Also, can you please let me know if your board was missing the bootloader, and if you were able to get it reflashed?
Not sure if you want private e-mail to report troubles with the AVR or if I should put it on dev@... For now I've just done a straight reply but I'm happy to widen things.
Either but anyhow my sensors board really isn't doing what I would expect.
I've run a quite a few different experiments after looking at the schematic to try and figure out what is going on. The (somewhat lengthy) results are as follows:
When power is applied to baseboard (Dragonboard 410c in my case) the PB5 LED (red) comes on briefly then goes out and it replaced by the reset LED (blue).
avrdude (run via make upload) fails with "avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00" errors. When avrdude is run the blue LED goes out and PB5 starts to blink.
Sounds like the bootloader is indeed missing and the manufacturing test sketch is still on the board. The test sketch blinks LEDs on all the pins.
- Running avrdude again interrupts the timing of the blink sequence It looks like avrdude can place the AVR into reset.reset.
Yes, that sounds right.
Shorting UART0 TX/RX on the LS connector (with the sensors board not fitted) results in character echo so we know the Dragonboard UART is able to send receive characters.
Shorting TX/RX after level shifting does *not* result in character echo. I tried on the arduino connector (P5) and directly on AVR pins 30 and 31.
This may not work as the AVR is also driving the UART RX signal. It probably prevents the signal from going low enough to be detected.
- I can light D7 using GPIO36 and the sysfs interface although the lamp strength is very weak.
I will check into that on my board.
Connecting a SW to P12 allows me to read the state of the switch. D7 also lights up and the lamp strength is much brighter. This is since in both cases
USBtinyISP cannot program the AVR using the ISP connector. I have checked the programmer with another ATMega328P based board and it is working OK.
I've not tried the ISP connector. It may be that we screwed it up somehow. George, have you tried it? This was the very first batch of boards, so there are things that I know are wrong and will be fixed before going into production.
... avrdude: Using SCK period of 10 usec avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check.
- (I suspect you have already discovered this but just in case...) the P2 (arduino 1x10) and P3 (ISP) are too close together to allow a normal IDC connector to be attached to P3. ;-)
For the next run I want to move the ISP connector down to the same location it is on a real arduino. That will solve the connector problem and also make it compatible with more shields.
I'm pretty confused at this point, to the point of suspecting multiple faults. Next steps for me will be with a continuity tester...
Actually, most of this sounds to be symptoms of a missing bootloader. Since you can't get USBtinyISP to program the board, do you have an arduino board handy that you can run the ArduinoISP sketch on? I used the following instructions for flashing the bootloader:
https://www.arduino.cc/en/Tutorial/ArduinoISP
Feel free to make comments on the Getting Started guide as you find things.
https://docs.google.com/document/d/1GNoC-1C1xcejgLLvgm1JbpF7blwJigXq5XIB3Fvn...
g.
On Sep 30, 2015, at 8:20 AM, Grant Likely grant.likely@linaro.org wrote:
[cc'ing dev list. This can be discussed in public]
On Wed, Sep 30, 2015 at 12:37 PM, Daniel Thompson <daniel.thompson@linaro.org mailto:daniel.thompson@linaro.org> wrote:
Hi Grant
On 28/09/15 15:57, Grant Likely wrote:
On Mon, Sep 28, 2015 at 3:47 PM, Grant Likely grant.likely@linaro.org wrote:
Update on the Sensors board.
Unfortunately, some of the boards got shipped out without the Arduino bootloader installed on the Atmel. Before you can use the procedure in the starter guide, you'll need to disconnect the Sensors board from your 96boards baseboard and flash the bootloader. Pretty much any flashing method will work, but the easiest is probably to use another Arduino as a programmer as documented here (unless you already have an AVR-ISP programmer, in which case use that):
https://www.arduino.cc/en/Tutorial/ArduinoISP
I've also updated the getting started guide.
Sorry for the inconvenience. Let me know if you have any trouble flashing the bootloader.
Also, can you please let me know if your board was missing the bootloader, and if you were able to get it reflashed?
Not sure if you want private e-mail to report troubles with the AVR or if I should put it on dev@... For now I've just done a straight reply but I'm happy to widen things.
Either but anyhow my sensors board really isn't doing what I would expect.
I've run a quite a few different experiments after looking at the schematic to try and figure out what is going on. The (somewhat lengthy) results are as follows:
- When power is applied to baseboard (Dragonboard 410c in my case) the
PB5 LED (red) comes on briefly then goes out and it replaced by the reset LED (blue).
- avrdude (run via make upload) fails with "avrdude: stk500_getsync()
attempt 1 of 10: not in sync: resp=0x00" errors. When avrdude is run the blue LED goes out and PB5 starts to blink.
Sounds like the bootloader is indeed missing and the manufacturing test sketch is still on the board. The test sketch blinks LEDs on all the pins.
- Running avrdude again interrupts the timing of the blink sequence
It looks like avrdude can place the AVR into reset.reset.
Yes, that sounds right.
- Shorting UART0 TX/RX on the LS connector (with the sensors board
not fitted) results in character echo so we know the Dragonboard UART is able to send receive characters.
- Shorting TX/RX after level shifting does *not* result in character
echo. I tried on the arduino connector (P5) and directly on AVR pins 30 and 31.
This may not work as the AVR is also driving the UART RX signal. It probably prevents the signal from going low enough to be detected.
- I can light D7 using GPIO36 and the sysfs interface although the
lamp strength is very weak.
I will check into that on my board.
- Connecting a SW to P12 allows me to read the state of the switch.
D7 also lights up and the lamp strength is much brighter. This is since in both cases
- USBtinyISP cannot program the AVR using the ISP connector. I have
checked the programmer with another ATMega328P based board and it is working OK.
I've not tried the ISP connector. It may be that we screwed it up somehow. George, have you tried it?
No - but I successfully programmed the bootloader onto the sensor board using another Arduino Uno (actually the original CircuitCo board) and the instructions in the link below. Then everything started working, though you do need to do the stty -F /dev/ttyxxx -hupcl to bring the board out of reset after uploading a sketch.
This was the very first batch of boards, so there are things that I know are wrong and will be fixed before going into production.
... avrdude: Using SCK period of 10 usec avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check.
- (I suspect you have already discovered this but just in case...) the
P2 (arduino 1x10) and P3 (ISP) are too close together to allow a normal IDC connector to be attached to P3. ;-)
For the next run I want to move the ISP connector down to the same location it is on a real arduino. That will solve the connector problem and also make it compatible with more shields.
I'm pretty confused at this point, to the point of suspecting multiple faults. Next steps for me will be with a continuity tester...
Actually, most of this sounds to be symptoms of a missing bootloader. Since you can't get USBtinyISP to program the board, do you have an arduino board handy that you can run the ArduinoISP sketch on? I used the following instructions for flashing the bootloader:
https://www.arduino.cc/en/Tutorial/ArduinoISP https://www.arduino.cc/en/Tutorial/ArduinoISP
Feel free to make comments on the Getting Started guide as you find things.
https://docs.google.com/document/d/1GNoC-1C1xcejgLLvgm1JbpF7blwJigXq5XIB3Fvn... https://docs.google.com/document/d/1GNoC-1C1xcejgLLvgm1JbpF7blwJigXq5XIB3FvnuIE/edit#
g.
On 30/09/15 13:20, Grant Likely wrote:
- USBtinyISP cannot program the AVR using the ISP connector. I have checked the programmer with another ATMega328P based board and it is working OK.
I've not tried the ISP connector. It may be that we screwed it up somehow. George, have you tried it? This was the very first batch of boards, so there are things that I know are wrong and will be fixed before going into production.
... avrdude: Using SCK period of 10 usec avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check.
- (I suspect you have already discovered this but just in case...) the P2 (arduino 1x10) and P3 (ISP) are too close together to allow a normal IDC connector to be attached to P3. ;-)
For the next run I want to move the ISP connector down to the same location it is on a real arduino. That will solve the connector problem and also make it compatible with more shields.
I'm pretty confused at this point, to the point of suspecting multiple faults. Next steps for me will be with a continuity tester...
Actually, most of this sounds to be symptoms of a missing bootloader. Since you can't get USBtinyISP to program the board, do you have an arduino board handy that you can run the ArduinoISP sketch on? I used the following instructions for flashing the bootloader:
Will do. I haven't got a proper arduino to hand but I can fudge it with an old breakout board...
Daniel.
On 09/30/2015 08:20 AM, Grant Likely wrote:
Update on the Sensors board.
Unfortunately, some of the boards got shipped out without the Arduino bootloader installed on the Atmel. Before you can use the procedure in the starter guide, you'll need to disconnect the Sensors board from your 96boards baseboard and flash the bootloader. Pretty much any flashing method will work, but the easiest is probably to use another Arduino as a programmer as documented here (unless you already have an AVR-ISP programmer, in which case use that):
are there any plans to create another accessory sensor board (just like this one) that only provides the same standard form factor and connectors to buses and sensors but without a micro-controller in it?
Maybe it could be advertised under "miscellaneous" accessories below? Not sure who/how gets decided what goes in here. https://www.96boards.org/products/accessories/
We demoed an early Xenomai release showing realtime control from userspace Linux on aarch64 last week during Connect using the Hikey6220; some of us would be very interested on having a bare sensor board like this (just for commodity of access) to build some prototypes.
On Wed, Sep 30, 2015 at 3:31 PM, Jorge Ramirez-Ortiz jorge.ramirez-ortiz@linaro.org wrote:
On 09/30/2015 08:20 AM, Grant Likely wrote:
Update on the Sensors board.
Unfortunately, some of the boards got shipped out without the Arduino bootloader installed on the Atmel. Before you can use the procedure in the starter guide, you'll need to disconnect the Sensors board from your 96boards baseboard and flash the bootloader. Pretty much any flashing method will work, but the easiest is probably to use another Arduino as a programmer as documented here (unless you already have an AVR-ISP programmer, in which case use that):
are there any plans to create another accessory sensor board (just like this one) that only provides the same standard form factor and connectors to buses and sensors but without a micro-controller in it?
Yes. We have a design called the Grove board and we'll be doing a prototype run of it in the next week or so. I don't know if we will manufacture and sell it commercially though.
Design files are here:
https://git.linaro.org/people/grant.likely/96boards-grove.git
Maybe it could be advertised under "miscellaneous" accessories below? Not sure who/how gets decided what goes in here. https://www.96boards.org/products/accessories/
We demoed an early Xenomai release showing realtime control from userspace Linux on aarch64 last week during Connect using the Hikey6220; some of us would be very interested on having a bare sensor board like this (just for commodity of access) to build some prototypes.
That would be great.
g.
On 9/30/15 7:57 AM, Daniel Thompson wrote:
On 30/09/15 13:20, Grant Likely wrote:
- USBtinyISP cannot program the AVR using the ISP connector. I have checked the programmer with another ATMega328P based board and it is working OK.
I can confirm this, my USBtinyISP won't work with the Sensors board (and I tried from both Linux PC and Mac) and does work (from both Linux PC and Mac) on other Arduino's.
I get the following from both Linux and Mac:
avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check.
Error while burning bootloader.
I used short jumpers to connect the USBtinyISP and the 6 pin ISP connector. As noted below you can't actually plug the USBtinyISP onto the ISP pins it's too tight a fit. Board powers up as expected but no joy on flashing the bootloader.
Tomorrow I'll clean my desk off, dig through my Arduino stuff and find a real Arduino and rig to flash it from that.
David
I've not tried the ISP connector. It may be that we screwed it up somehow. George, have you tried it? This was the very first batch of boards, so there are things that I know are wrong and will be fixed before going into production.
... avrdude: Using SCK period of 10 usec avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check.
- (I suspect you have already discovered this but just in case...) the P2 (arduino 1x10) and P3 (ISP) are too close together to allow a normal IDC connector to be attached to P3. ;-)
For the next run I want to move the ISP connector down to the same location it is on a real arduino. That will solve the connector problem and also make it compatible with more shields.
I'm pretty confused at this point, to the point of suspecting multiple faults. Next steps for me will be with a continuity tester...
Actually, most of this sounds to be symptoms of a missing bootloader. Since you can't get USBtinyISP to program the board, do you have an arduino board handy that you can run the ArduinoISP sketch on? I used the following instructions for flashing the bootloader:
Will do. I haven't got a proper arduino to hand but I can fudge it with an old breakout board...
Daniel. _______________________________________________ Dev mailing list Dev@lists.96boards.org https://lists.96boards.org/mailman/listinfo/dev
Try wiring it to the Arduino headers. Make sure the board is /not/ attached to the basebord when programming.
Can you try writing the programmer to the Arduino headers instead of the ISP connection?
g.
g. On 2 Oct 2015 01:51, "David Mandala" davidm@linaro.org wrote:
On 9/30/15 7:57 AM, Daniel Thompson wrote:
On 30/09/15 13:20, Grant Likely wrote:
- USBtinyISP cannot program the AVR using the ISP connector. I have
checked the programmer with another ATMega328P based board and it is working OK.I can confirm this, my USBtinyISP won't work with the Sensors board (and I tried from both Linux PC and Mac) and does work (from both Linux PC and Mac) on other Arduino's.
I get the following from both Linux and Mac:
avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check.
Error while burning bootloader.
I used short jumpers to connect the USBtinyISP and the 6 pin ISP connector. As noted below you can't actually plug the USBtinyISP onto the ISP pins it's too tight a fit. Board powers up as expected but no joy on flashing the bootloader.
Tomorrow I'll clean my desk off, dig through my Arduino stuff and find a real Arduino and rig to flash it from that.
David
I've not tried the ISP connector. It may be that we screwed it up somehow. George, have you tried it? This was the very first batch of boards, so there are things that I know are wrong and will be fixed before going into production.
> ... > avrdude: Using SCK period of 10 usec > avrdude: initialization failed, rc=-1 > Double check connections and try again, or use -F to override > this check. > ~~~ > > 9. (I suspect you have already discovered this but just in case...) the > P2 (arduino 1x10) and P3 (ISP) are too close together to allow > a normal IDC connector to be attached to P3. ;-) > For the next run I want to move the ISP connector down to the same location it is on a real arduino. That will solve the connector problem and also make it compatible with more shields. I'm pretty confused at this point, to the point of suspecting multiple > faults. Next steps for me will be with a continuity tester... > Actually, most of this sounds to be symptoms of a missing bootloader. Since you can't get USBtinyISP to program the board, do you have an arduino board handy that you can run the ArduinoISP sketch on? I used the following instructions for flashing the bootloader: https://www.arduino.cc/en/Tutorial/ArduinoISPWill do. I haven't got a proper arduino to hand but I can fudge it with an old breakout board...
Daniel. _______________________________________________ Dev mailing list Dev@lists.96boards.org https://lists.96boards.org/mailman/listinfo/dev
-- David Mandala <davidma at linaro dot org> http://www.linaro.org/ Public Key id: 45B2D952 Murphy TX, 75094 +1.972.891.8436
On 02/10/15 07:04, Grant Likely wrote:
Try wiring it to the Arduino headers. Make sure the board is /not/ attached to the basebord when programming.
Can you try writing the programmer to the Arduino headers instead of the ISP connection?
Sorry for the delay but it took me a while to dig out an old (and until today, entirely unused) Pro Micro clone. With that I have been able to successfully program the bootloader onto the board.
Photos of the wiring are on flickr for anyone else in a hurry to do this with a Pro Micro (you also need to change "#define RESET SS" to "#define RESET 10" before uploading the sketch):
https://www.flickr.com/photos/daniel-thompson/21261178283/
Having done that I also wanted to check for potential problems on the ISP port:
1. Hooking up the Pro Micro to the ISP port also allows the board to be programmed OK, so no connectivity problems with the socket.
2. Hooking up exactly the same pinout to another AVR board also allows that board to be programmed, so no pin out problems with the socket.
3. USBtinyISP has 1.5k current limiting resistors on the SCK and MOSI lines whilst the sensors board as a 620R+LED circuit attached to SCK. My test board also has 1k+LED circuit attached to SCK and this works OK.
Based on #3 I cracked open by programmer and short circuited R7 (i.e. bypassing the programmer boards current limit on SCK). With this modification I was successfully able to program the sensors board.
Any chance of a transistor switched LED circuit for SCK in v2? ;-) It would be good to be compatible with this fairly popular programmer.
Daniel.
On 2 Oct 2015 01:51, "David Mandala" <davidm@linaro.org mailto:davidm@linaro.org> wrote:
On 9/30/15 7:57 AM, Daniel Thompson wrote: On 30/09/15 13:20, Grant Likely wrote: 8. USBtinyISP cannot program the AVR using the ISP connector. I have checked the programmer with another ATMega328P based board and it is working OK. I can confirm this, my USBtinyISP won't work with the Sensors board (and I tried from both Linux PC and Mac) and does work (from both Linux PC and Mac) on other Arduino's. I get the following from both Linux and Mac: avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check. Error while burning bootloader. I used short jumpers to connect the USBtinyISP and the 6 pin ISP connector. As noted below you can't actually plug the USBtinyISP onto the ISP pins it's too tight a fit. Board powers up as expected but no joy on flashing the bootloader. Tomorrow I'll clean my desk off, dig through my Arduino stuff and find a real Arduino and rig to flash it from that. David I've not tried the ISP connector. It may be that we screwed it up somehow. George, have you tried it? This was the very first batch of boards, so there are things that I know are wrong and will be fixed before going into production. ~~~ ... avrdude: Using SCK period of 10 usec avrdude: initialization failed, rc=-1 Double check connections and try again, or use -F to override this check. ~~~ 9. (I suspect you have already discovered this but just in case...) the P2 (arduino 1x10) and P3 (ISP) are too close together to allow a normal IDC connector to be attached to P3. ;-) For the next run I want to move the ISP connector down to the same location it is on a real arduino. That will solve the connector problem and also make it compatible with more shields. I'm pretty confused at this point, to the point of suspecting multiple faults. Next steps for me will be with a continuity tester... Actually, most of this sounds to be symptoms of a missing bootloader. Since you can't get USBtinyISP to program the board, do you have an arduino board handy that you can run the ArduinoISP sketch on? I used the following instructions for flashing the bootloader: https://www.arduino.cc/en/Tutorial/ArduinoISP Will do. I haven't got a proper arduino to hand but I can fudge it with an old breakout board... Daniel. _______________________________________________ Dev mailing list Dev@lists.96boards.org <mailto:Dev@lists.96boards.org> https://lists.96boards.org/mailman/listinfo/dev -- David Mandala <davidma at linaro dot org> http://www.linaro.org/ Public Key id: 45B2D952 Murphy TX, 75094 +1.972.891.8436 <tel:%2B1.972.891.8436>
On Fri, Oct 2, 2015 at 10:30 AM, Daniel Thompson daniel.thompson@linaro.org wrote:
On 02/10/15 07:04, Grant Likely wrote:
Try wiring it to the Arduino headers. Make sure the board is /not/ attached to the basebord when programming.
Can you try writing the programmer to the Arduino headers instead of the ISP connection?
Sorry for the delay but it took me a while to dig out an old (and until today, entirely unused) Pro Micro clone. With that I have been able to successfully program the bootloader onto the board.
Photos of the wiring are on flickr for anyone else in a hurry to do this with a Pro Micro (you also need to change "#define RESET SS" to "#define RESET 10" before uploading the sketch):
https://www.flickr.com/photos/daniel-thompson/21261178283/
Having done that I also wanted to check for potential problems on the ISP port:
Hooking up the Pro Micro to the ISP port also allows the board to be programmed OK, so no connectivity problems with the socket.
Hooking up exactly the same pinout to another AVR board also allows that board to be programmed, so no pin out problems with the socket.
USBtinyISP has 1.5k current limiting resistors on the SCK and MOSI lines whilst the sensors board as a 620R+LED circuit attached to SCK. My test board also has 1k+LED circuit attached to SCK and this works OK.
Based on #3 I cracked open by programmer and short circuited R7 (i.e. bypassing the programmer boards current limit on SCK). With this modification I was successfully able to program the sensors board.
Any chance of a transistor switched LED circuit for SCK in v2? ;-) It would be good to be compatible with this fairly popular programmer.
Great work! Thanks for the debugging. Yes, I'll either put in a transistor, or remove the LED entirely.
g.
On 10/2/15 4:49 AM, Grant Likely wrote:
On Fri, Oct 2, 2015 at 10:30 AM, Daniel Thompson daniel.thompson@linaro.org wrote:
On 02/10/15 07:04, Grant Likely wrote:
Try wiring it to the Arduino headers. Make sure the board is /not/ attached to the basebord when programming.
Can you try writing the programmer to the Arduino headers instead of the ISP connection?
Sorry for the delay but it took me a while to dig out an old (and until today, entirely unused) Pro Micro clone. With that I have been able to successfully program the bootloader onto the board.
Photos of the wiring are on flickr for anyone else in a hurry to do this with a Pro Micro (you also need to change "#define RESET SS" to "#define RESET 10" before uploading the sketch):
https://www.flickr.com/photos/daniel-thompson/21261178283/
Having done that I also wanted to check for potential problems on the ISP port:
Hooking up the Pro Micro to the ISP port also allows the board to be programmed OK, so no connectivity problems with the socket.
Hooking up exactly the same pinout to another AVR board also allows that board to be programmed, so no pin out problems with the socket.
USBtinyISP has 1.5k current limiting resistors on the SCK and MOSI lines whilst the sensors board as a 620R+LED circuit attached to SCK. My test board also has 1k+LED circuit attached to SCK and this works OK.
Based on #3 I cracked open by programmer and short circuited R7 (i.e. bypassing the programmer boards current limit on SCK). With this modification I was successfully able to program the sensors board.
Thank you sir, I followed your method and shorted out R7 and it works from my Mac have not bothered to test from Linux as it's flashed. Yea.
Any chance of a transistor switched LED circuit for SCK in v2? ;-) It would be good to be compatible with this fairly popular programmer.
Great work! Thanks for the debugging. Yes, I'll either put in a transistor, or remove the LED entirely.
g.
On 02/10/15 10:49, Grant Likely wrote:
Based on #3 I cracked open by programmer and short circuited R7 (i.e. bypassing the programmer boards current limit on SCK). With this modification I was successfully able to program the sensors board.
Any chance of a transistor switched LED circuit for SCK in v2? ;-) It would be good to be compatible with this fairly popular programmer.
Great work! Thanks for the debugging. Yes, I'll either put in a transistor, or remove the LED entirely.
Well. From my perspective having a Blink example work out of the box is a pretty good feature. It makes getting started feel pretty effortless.
Daniel.
+1 This is a good "hello world" feature. G
Sent from my iPhone
On Oct 2, 2015, at 12:11 PM, Daniel Thompson daniel.thompson@linaro.org wrote:
On 02/10/15 10:49, Grant Likely wrote:
Based on #3 I cracked open by programmer and short circuited R7 (i.e. bypassing the programmer boards current limit on SCK). With this modification I was successfully able to program the sensors board.
Any chance of a transistor switched LED circuit for SCK in v2? ;-) It would be good to be compatible with this fairly popular programmer.
Great work! Thanks for the debugging. Yes, I'll either put in a transistor, or remove the LED entirely.
Well. From my perspective having a Blink example work out of the box is a pretty good feature. It makes getting started feel pretty effortless.
Daniel.
On Fri, Oct 2, 2015 at 5:11 PM, Daniel Thompson daniel.thompson@linaro.org wrote:
On 02/10/15 10:49, Grant Likely wrote:
Based on #3 I cracked open by programmer and short circuited R7 (i.e. bypassing the programmer boards current limit on SCK). With this modification I was successfully able to program the sensors board.
Any chance of a transistor switched LED circuit for SCK in v2? ;-) It would be good to be compatible with this fairly popular programmer.
Great work! Thanks for the debugging. Yes, I'll either put in a transistor, or remove the LED entirely.
Well. From my perspective having a Blink example work out of the box is a pretty good feature. It makes getting started feel pretty effortless.
Oops, I was looking at the reset LED. I just looked at the schematic for the Arduino UNO, and it has exactly the same circuit, but it uses a 1k resistor on the LED (same as your test board). It should be as simple as changing the R to 1k on the next board. I'll get some 1k resistors delivered and give it a try.
It seems I need to order myself a USBTinyISP. :-)
g.
On 10/2/15 12:18 PM, Grant Likely wrote:
On Fri, Oct 2, 2015 at 5:11 PM, Daniel Thompson daniel.thompson@linaro.org wrote:
On 02/10/15 10:49, Grant Likely wrote:
Based on #3 I cracked open by programmer and short circuited R7 (i.e. bypassing the programmer boards current limit on SCK). With this modification I was successfully able to program the sensors board.
Any chance of a transistor switched LED circuit for SCK in v2? ;-) It would be good to be compatible with this fairly popular programmer.
Great work! Thanks for the debugging. Yes, I'll either put in a transistor, or remove the LED entirely.
Well. From my perspective having a Blink example work out of the box is a pretty good feature. It makes getting started feel pretty effortless.
Oops, I was looking at the reset LED. I just looked at the schematic for the Arduino UNO, and it has exactly the same circuit, but it uses a 1k resistor on the LED (same as your test board). It should be as simple as changing the R to 1k on the next board. I'll get some 1k resistors delivered and give it a try.
It seems I need to order myself a USBTinyISP. :-)
g.
It's very handy and cheap. Had mine for years now.
On 02/10/15 18:18, Grant Likely wrote:
On Fri, Oct 2, 2015 at 5:11 PM, Daniel Thompson daniel.thompson@linaro.org wrote:
On 02/10/15 10:49, Grant Likely wrote:
Based on #3 I cracked open by programmer and short circuited R7 (i.e. bypassing the programmer boards current limit on SCK). With this modification I was successfully able to program the sensors board.
Any chance of a transistor switched LED circuit for SCK in v2? ;-) It would be good to be compatible with this fairly popular programmer.
Great work! Thanks for the debugging. Yes, I'll either put in a transistor, or remove the LED entirely.
Well. From my perspective having a Blink example work out of the box is a pretty good feature. It makes getting started feel pretty effortless.
Oops, I was looking at the reset LED. I just looked at the schematic for the Arduino UNO, and it has exactly the same circuit, but it uses a 1k resistor on the LED (same as your test board). It should be as simple as changing the R to 1k on the next board. I'll get some 1k resistors delivered and give it a try.
On the UNO has a yellow LED attached to GND rather than a red LED attached to Vcc. I think both these things contribute to making the circuit work!
Based on a bit of back-of-the-envelop scribbling...
I think with the UNO circuit the AVR will see logic levels of 0V and ~3.2V; not perfect but it should work[1].
On sensors board, even with a 1K resister we will get logic levels of ~2V and 5V and this (probably ;-) won't work.
Note that the voltage dropped by the LED contributes to circuit robustness so in addition to changing the circuit, swapping the colours of D3 and D2 (so PB5 is green and PWR is red) would definitely be worthwhile.
Daniel.
[1] Based on logic levels I found in: https://learn.sparkfun.com/tutorials/logic-levels#arduino-logic-levels
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Daniel Thompson -
David Mandala -
George Grey -
Grant Likely -
Jorge Ramirez-Ortiz