teapot418
Posts: 6
Joined: Tue Jan 09, 2018 6:42 pm

Re: Gertbot

Thu Jan 11, 2018 9:07 pm

Thank you Gert, I appreciate you taking the time to look into this. I have just copied a fresh version of noobs to my SD card and will follow the instructions at https://www.gertbot.com/pi3.html as you suggest. But I'll have to wait until the television becomes free!

Can you confirm that I should download version 2.6 of all code from the https://www.gertbot.com/updates.html page - this does seems
to be different to the code on the https://www.gertbot.com/download.html page.

Best wishes once again
Richard

User avatar
Gert van Loo
Posts: 2452
Joined: Tue Aug 02, 2011 7:27 am
Contact: Website

Re: Gertbot

Thu Jan 11, 2018 10:57 pm

Yes 2.6 is the latest but I have been asked for 2.8 which I will try to get out this weekend.
I have not done so as I have not had time to update the C or python drivers.

Revision 2.7 has support for servo motors. It does not use the power bridge at all but outputs a
3.3Volt variable pulse width to control servo's. Whilst testing I was surprised to see how few servos
work according to the standard. On many I had to make the pulse width <1ms or >2ms to reach the end positions.
Therefore I had to build-in compensation for that. You set the min & max pulse width.
Then when you tell it to go to the middle position it will work out where that is.

Revision 2.8 has support for ramping up and down on the stepper motor speed
sort of like the brushed motors. The issue was that it has to stop exactly when it has reached its
minimum step speed which required some nice calculations as to when to start ramping down.
(Which in short step sequences maybe half way when it is still ramping up)

So this weekend I plan to release the GUI 2.8 and the code for the board plus the manual
but not yet the C or Python drivers.

teapot418
Posts: 6
Joined: Tue Jan 09, 2018 6:42 pm

Re: Gertbot

Thu Jan 11, 2018 11:14 pm

Still not working - fresh install, (I think I have) followed your instructions - the gui is OK, but no boards are found :(

I do still have wifi (but not bluetooth) and you have mentioned a couple of times that this ought to be disabled, so I think we may still have different configurations. Or could possibly have somehow fried my gertbot - the heartbeat on the board still flashes...

Here are how the gpio pins look, how my config and cmline files look.

Code: Select all

pi@raspberrypi:~/Downloads $ sudo gpio readall
 +-----+-----+---------+------+---+---Pi 3---+---+------+---------+-----+-----+
 | BCM | wPi |   Name  | Mode | V | Physical | V | Mode | Name    | wPi | BCM |
 +-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+
 |     |     |    3.3v |      |   |  1 || 2  |   |      | 5v      |     |     |
 |   2 |   8 |   SDA.1 |   IN | 1 |  3 || 4  |   |      | 5v      |     |     |
 |   3 |   9 |   SCL.1 |   IN | 1 |  5 || 6  |   |      | 0v      |     |     |
 |   4 |   7 | GPIO. 7 |   IN | 1 |  7 || 8  | 1 | ALT0 | TxD     | 15  | 14  |
 |     |     |      0v |      |   |  9 || 10 | 1 | ALT0 | RxD     | 16  | 15  |
 |  17 |   0 | GPIO. 0 |   IN | 0 | 11 || 12 | 0 | IN   | GPIO. 1 | 1   | 18  |
 |  27 |   2 | GPIO. 2 |   IN | 0 | 13 || 14 |   |      | 0v      |     |     |
 |  22 |   3 | GPIO. 3 |   IN | 0 | 15 || 16 | 0 | IN   | GPIO. 4 | 4   | 23  |
 |     |     |    3.3v |      |   | 17 || 18 | 0 | IN   | GPIO. 5 | 5   | 24  |
 |  10 |  12 |    MOSI |   IN | 0 | 19 || 20 |   |      | 0v      |     |     |
 |   9 |  13 |    MISO |   IN | 0 | 21 || 22 | 1 | IN   | GPIO. 6 | 6   | 25  |
 |  11 |  14 |    SCLK |   IN | 0 | 23 || 24 | 1 | IN   | CE0     | 10  | 8   |
 |     |     |      0v |      |   | 25 || 26 | 1 | IN   | CE1     | 11  | 7   |
 |   0 |  30 |   SDA.0 |   IN | 1 | 27 || 28 | 1 | IN   | SCL.0   | 31  | 1   |
 |   5 |  21 | GPIO.21 |   IN | 1 | 29 || 30 |   |      | 0v      |     |     |
 |   6 |  22 | GPIO.22 |   IN | 1 | 31 || 32 | 0 | IN   | GPIO.26 | 26  | 12  |
 |  13 |  23 | GPIO.23 |   IN | 0 | 33 || 34 |   |      | 0v      |     |     |
 |  19 |  24 | GPIO.24 |   IN | 0 | 35 || 36 | 0 | IN   | GPIO.27 | 27  | 16  |
 |  26 |  25 | GPIO.25 |   IN | 0 | 37 || 38 | 0 | IN   | GPIO.28 | 28  | 20  |
 |     |     |      0v |      |   | 39 || 40 | 0 | IN   | GPIO.29 | 29  | 21  |
 +-----+-----+---------+------+---+----++----+---+------+---------+-----+-----+
 | BCM | wPi |   Name  | Mode | V | Physical | V | Mode | Name    | wPi | BCM |
 +-----+-----+---------+------+---+---Pi 3---+---+------+---------+-----+-----+

pi@raspberrypi:~/Downloads $ file /dev/ttyAMA0 
/dev/ttyAMA0: character special (204/64)

pi@raspberrypi:~/Downloads $ more /boot/cmdline.txt 
dwc_otg.lpm_enable=0 root=/dev/mmcblk0p7 rootfstype=ext4 elevator=deadline fsck.
repair=yes rootwait splash plymouth.ignore-serial-consoles

pi@raspberrypi:~/Downloads $ tail -2 /boot/config.txt 
dtoverlay=pi3-disable-bt
enable_uart=1

If you have any more ideas, I'd be grateful - I would even be happy to package up the boards and send them to you to take a look at if you would be willing? If my gertbot works on your pi3, that would at least give me confidence that it is worth continuing to look at this.

cheers
Rich

ps - I don't know systemctl, but I have also issued
sudo systemctl stop bluetooth.service
but that does not appear to have made any difference either

User avatar
Gert van Loo
Posts: 2452
Joined: Tue Aug 02, 2011 7:27 am
Contact: Website

Re: Gertbot

Thu Jan 11, 2018 11:36 pm

First note that I have updated the gertbot webpages several times over the last two days.
There are tested instruction on there: https://www.gertbot.com/pi3.html

domoticom had even more problems (Qt4 libraries where missing) but I manged to help him out and for him it now all works: viewtopic.php?f=45&t=130475
I have to assume from that that the instructions on the gertbot webpage are correct but they
have been tested only with the latest stretch build.

What I learned in the last two days:
1/ Wifi is still working with my gertbot, In fact the picture below has been obtained using VNC connected over WIFI.
2/ Do NOT touch the user settings with the GUI 'to enable the UART interface.:
uart_interface.png
uart_interface.png (33.98 KiB) Viewed 728 times
If you have enabled it, disable it again but then you have to edit the /boot/config.txt file again to set enable_uart=1.
I suspect somebody is installing a SW bit-bang driver which is not at all compatible with the actual hardware UART.

===========

I will try tomorrow with an fresh pre-stretch image.
I think you have one of those because on the latest image the whole GUI will not start
due to the missing qt4 libraries.

teapot418
Posts: 6
Joined: Tue Jan 09, 2018 6:42 pm

Re: Gertbot

Thu Jan 11, 2018 11:42 pm

I followed the instructions to add the qt4 libraries - I think I'm as apt-get upgraded as I can be. I'm going to leave it for tonight - I'll try and read more tomorrow

Best wishes
Richard

User avatar
Gert van Loo
Posts: 2452
Joined: Tue Aug 02, 2011 7:27 am
Contact: Website

Re: Gertbot

Fri Jan 12, 2018 11:26 am

Downloading the QT4 libraries.
You only need to download the QT4 runtime libraries if you get an error message saying "libQtGui.so.4: cannot open shared object file: No such file or directory"
At the moment this is the case if you use a stretch image. (uname -r gives as output "4.9.41-v7+")
In that case there are instructions here: https://www.gertbot.com/updates.html

If you are running an older jessie image (uname -r gives as output "4.4.50-v7+") then you do NOT need to download the qt4 libraries as they are provided.

Pi-3 UART
In a Pi-3 in both versions to get the UART working the following is needed:

Add to the /boot/config.txt file:
dtoverlay=pi3-disable-bt
enable_uart=1

Remove "console=serial0,115200 console=tty1" from the /boot/cmdline.txt file

Do NOT touch the user settings with the GUI 'to enable the UART interface.

I have tested this yesterday with a stretch build and today with a jessie build.
Both freshly downloaded with no other modifications.

teapot418
Posts: 6
Joined: Tue Jan 09, 2018 6:42 pm

Re: Gertbot

Sat Jan 20, 2018 5:25 pm

Hi Gert,

just to let you know, I decided to order a re[placement gertbot which arrived this week. I have just wired it up and plugged it into the pi3 and it worked first time - yay! So I think I must have somehow damaged the gertbot I was trying to get working previously. I'm very pleased - we can now crack on with a bit of coding and will hopefully be ready for some piwars in April - although there is still an awful lot to do!

Best wishes,
Richard

User avatar
Gert van Loo
Posts: 2452
Joined: Tue Aug 02, 2011 7:27 am
Contact: Website

Re: Gertbot

Sat Jan 20, 2018 5:47 pm

Great to hear that.
Note that last weekend I did mange to release version 2.8 which supports ramping of the stepper motors.

If you work with motors and motion you will find that slow starting/stopping is not a luxury, it is mandatory.
I found out when I built the 'Toast-e' prototype.

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