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Raspberry Pi LEGO HAT

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2 minutes ago, JaBaCaDaBra said:

I hope to receive my hat this week and will try to figure out.

Yes, let us know how i works.

The GPIOS you find in the documents

GPIO Use Status
GPIO0/1 ID prom
GPIO4 Reset
GPIO14 Tx
GPIO15 Rx
GPIO16 RTS unused
GPIO17 CTS unused
 

with the remark:

The following pins are used by the Build HAT itself and you should not connect anything to them.

And the syntax for a motor is

from buildhat import Motor
motor_a = Motor('A')
motor_a.run_for_seconds(5)

So there is - at first sight - no idea how to adress something like "HAT2"

Perhaps helpful: a good documentation of syntax can be found here:

https://github.com/raspberrypi/documentation/blob/develop/documentation/asciidoc/accessories/build-hat/introduction.adoc

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Does anyone know if the multiple build HATs can be stacked together? I saw a discussion on the RPI4 Build Hat page but there isn't a clear conclusion on this subject (apart from saying refer to the communication interface spec) :(

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You can't stack them directly, bacuse there are no pins on top.

You could perhaps use any adpater like @JaBaCaDaBra showed.
But that doesn't solve the problem, that you cannot address the HAT via the software coming with the HAT.

The Idea of the HAT is a ready to use solution.
 

 

 

 

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11 minutes ago, Lok24 said:

You can't stack them directly, bacuse there are no pins on top.

You could perhaps use any adpater like @JaBaCaDaBra showed.
But that doesn't solve the problem, that you cannot address the HAT via the software coming with the HAT.

The Idea of the HAT is a ready to use solution.
 

 

 

 

But offcourse there's always ye good 'ol soldering iron.
Once, back in 1978, they said you couln't add 64Kb RAM to a VIC-20, I proved that it was possible and it even still works fine in '21 :laugh:

soldeerbouten.jpg

Edited by JaBaCaDaBra

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Hi @JaBaCaDaBra

Sure, I used my C64 to drive my model railway via PWM, directly generate by an interrupt assembler program, so 60Hz. And saved the programs via a self made interface on my magnetic tape recorder with reels.

Nice Picture, thanks. Got a Weller, too. since -hm- 40 years?

But if you wand to do programming and soldering: why do you use the HAT? That's my point.

 

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1 minute ago, Lok24 said:

why do you use the HAT?

I'm not familiair with Python (better say, I'm a noob)
So this looked to me an easy way to make a start.
learn from others, don't re-invent the wheel but improve it where you can.

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44 minutes ago, JaBaCaDaBra said:

I'm not familiair with Python (better say, I'm a noob)

Correct! That's the idea!

But as I wrote: you have three lines to  start a motor on Port A

from buildhat import Motor ### THIS ist part of the HAT-Bundel
motor_a = Motor('A') #define the Motor on Port A
motor_a.run_for_seconds(5) # do somthing

That's simple.

But if you could stack the HW you needed somthing like

motor_a = Motor('HAT1','A') #define the Motor on HAT 1 Port A

or the sofware had to add more Ports like E,F,G,H .....

See what I mean?

Edited by Lok24

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How about bankselecting.

One of the pins must be the selector.

it shouldn't be too hard to add some selection hardware, or maybe even multiplex the hat.

(thats btw the exact same as I did with the VIC since a 6502µP cant address more than FFFF adresses and 20K was allready taken bij kernelrom, charom and interpreter rom.)

Edited by JaBaCaDaBra

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@JaBaCaDaBra yes, nice idea

you than just have to take care, that no other access is in  progress (i.e. aksing the roration of a motor  on a HAT momentarily "disconnected".
But that all can be solved, I'm sure.

 

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Just add some kind of blanking.

on switch of hat, stop all functions on current hat
it's still all brainwaves.

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12 hours ago, JaBaCaDaBra said:

But offcourse there's always ye good 'ol soldering iron.

That IS a nice photograph. It looks like some advanced Spanish inquisition set-up - but man, these Wellers ... I am on Chinese stuff (I believe) - works, though. Only one - and the dentist equipment is missing as well here - that comes in very handy I believe! So each station for individual temperatures? 145°C for what? Cool, really cool!!!

Back in the days, they said of course you can upgrade a Sinclair Spectrum to 48k - but you need the 32kx1bit RAMs (which were never sold in any store as they are defective 64k chips with one bank messed up :pir-skel: But the 64kx1bit chips worked perfectly well with on bank. Activating the other was total fun. More or less useless but fun.

And yes - it still works and controls my LEGO trains :pir-stareyes:OK, with a little help from an ESP32 ...

Best
Thorsten

 

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9 hours ago, Toastie said:

So each station for individual temperatures?

1 desoldering
3 different power from very fine till 150watt
 

9 hours ago, Toastie said:

145°C for what?

Just switched on for the picture :laugh:
365° for most jobs, 400° for Roadrunner repair.

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To-ta-lly cool! This is really a nice place to work!

Have a nice day,
Thorsten

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Some explanation: From left to right
1: 80 Watts desoldering iron (needs compressor too) Expensive to buy but also expensive to maintain.
2: 50 Watts iron, used for 99% of the solderjobs
3: 25 Watts iron, rarely used for extreme fine work and for roadrunnering at 400 degreees
4: 150 Watts iron, used for connectors, large bridge rectifiers etc.

Power is important, soldering needs to be done as fast as possible and trying to solder a large component with a subtile small iron takes to much time that you will damage the circuitboard badly.
About power, these irons are temperature controlled so a 150 Watt iron will not function as redhot heater (or cigarette lighter)
These irons CAN give all heating power a jobs needs but won't overheat.

 

soldeerbouten2.jpg

Edited by JaBaCaDaBra

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For connecting a lego to a raspberry I currently use a buwizz 3.0 and a battery powered pi 3 A+. 

That's really a neat addition for Rpi and really in line with their STEM/education-first philosophy ! 

A better support for battery would have been neat, the only thing missing IMO, the big jack connector is not really ideal for that but it's possible with it I guess

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On 30/10/2021 at 16:42, JaBaCaDaBra said:

J'attends toujours le chapeau (sortie du 2 novembre, disent-ils)
Mais regardez ce qui est arrivé aujourd'hui:wub:

lego_maker_plate.jpg

Is it an official piece?

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13 hours ago, Micka said:

Is it an official piece?

Yes,
This is the not yet available "Maker Plate" for the Raspberry.

PANEL 11X15 W/ PCB HOLES
LegoID: 6318207
Number: 65817

It will come available in Spike set 45681

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On 11/2/2021 at 2:40 AM, JaBaCaDaBra said:

Yes,
This is the not yet available "Maker Plate" for the Raspberry.

How did you get and/or order it?  I have the Spike Prime set + the older version of the Expansion set, and would like to get this part so I can put together a Raspberry Pi Kit, too.

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Hi all,

My build hat arrived today and I am just testing it now but is already facing some strange issues.

The moment I plugged in the a motor to any of the port the motor will start to spin like crazy. The only way you can stop it appears to be to write a python program and issue a stop command.Is anyone facing similar issue?

Thanks for your help in advance.

:(

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For those of you having the same issues as I had, it turned out the BuildHat doesn't support the latest version of Raspberry OS (bulleyes). To get the buildhat to run you have to use 2021-05-07-raspios-buster-armhf.zip, and then do a

sudo pip3 install buildhat

Hope this will help someone out there using the BuildHat, good luck!

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