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I finally broke down and bought a raspberry pi. I feel like it's cheating since it's a small computer, not an IoT device as such.
However, it runs linux and will run GCC so I can use it to test out my driver code directly without long dev cycles i usually deal with uploading my binaries via serial.
I bought a 512GB microsd card for storage
I'm hooking it into my primary display and I have a keyboard i can use with it. I also have a 5" hdmi touch display i bought for my logic probe/scope, but i can use it for this too.
Any other "must have" gear I should get with it?
Real programmers use butterflies
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I am not sure about "must" but I have a case with fan, breakout expansion board, expansion board 1 to 3 (requires extender with the case I use). Depends on how many/what kind of devices you want to use. I probably wouldn't load up on stuff, easy to do it as you go with one day delivery from Amazon. Newark takes longer.
If you can keep your head while those about you are losing theirs, perhaps you don't understand the situation.
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A joystick, of course. 
"In testa che avete, Signor di Ceprano?"
-- Rigoletto
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I got a couple of Pi and Arduino setups, with mounting points for both a Pi and an Arduino, plus a breadboard. Like this one, although I just got one from Amazon: Arduino/Raspberry-PI Breadboarding Platform mount | MPJA.COM[^] I know that platform works with the Pi 2B and 3B, but I haven't tried it with a 4B yet.
If you're going to be mixing Pi's and Arduinos, I'd suggest adding a level shifter to protect the 3.3v Pi from the 5v Arduino signals; you can use I2C without it, but adding it means you can make wiring errors, etc. without destroying the Pi. I got a level shifter from SparkFun after seeing a classmate wreck 2 Pi's in less than 5 minutes. $3 to protect a $30 Pi seemed like a wise move after that!
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I don't really use Arduinos that much. I use ESP32s. I'm starting to dabble with ARMs though I hate their toolchain so who knows if I'll continue with those.
Still, I'm 3.3v everywhere.
Frankly Arduinos are expensive for what they are, and not very useful for me other than as toys.
Real programmers use butterflies
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honey the codewitch wrote: I bought a 512GB microsd card for storage
512GB ?? That's more storage than I have on my (work, private, play, one-and-only) laptop... that I use for development, offsite backup of client software during upgrades, hosting multiple non-work databases, running MySql and Sql Server, multiple versions of Visual Studio plus all the code I've ever written (over 460 separate projects), plus all my photographs of the "digital" era (from 2005). ... and I'm still only half-full!
(In 1992 I was made redundant when my employer closed down. I got my pick of PCs (at cost, based on the machine's spec) and managed to nab one with a 40Mb disk. Because of the way Win3.1 was configured it only reported a single 32Mb partition, but once I'd lugged it home I setup a second 8Mb partition too. So I had the last laugh!  )
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Yes. half a terabyte.
I didn't want to run out of room, and it was $35
Real programmers use butterflies
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Linky?
All 512GB MicroSD cards I can find on Amazon right now are starting at CAD$80.
Well, there are a few that go for $20-something, but those have to be crap.
If you haven't done so already, I suggest you try filling that 512GB card with actual data. Then try to read it back. Only then should you trust it to have that actual capacity.
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I thought $35 was cheap, but whatever. if it's not 512GB i don't really care. i didn't look for the cheapest one or anything.
Real programmers use butterflies
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honey the codewitch wrote: if it's not 512GB i don't really care
I think you will care if you write to it and start encountering otherwise inexplicable failures, even if you stay well below the claimed capacity.
Years ago my employer got 64GB USB sticks (when those were still a new thing) for very cheap, for a trade show, and we loaded them up with marketing material. And while we only needed just a few hundreds of MBs (if that), some couldn't be written to or read back at all.
If it's too good to be true, that's usually the sort of device you're dealing with. In the end, they're not worth the aggravation, especially if you're gonna be using it as a daily thing.
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dandy72 wrote: If it's too good to be true, that's usually the sort of device you're dealing with. In the end, they're not worth the aggravation, especially if you're gonna be using it as a daily thing.
I mean, I agree with that. And I appreciate the heads up.
But here's the thing:
A) I didn't know that $35 was especially cheap. I haven't kept up on SD prices. I literally just bought the first one I found @ 512GB on amazon. I didn't care. Now that I know they should be $80 I'll bear that in mind.
B) That machine will never not be wipeable. In fact, the first thing I was going to do was copy the SD that ships with it - the one with raspian on it, to my PC. Then I am going to boot up, install VS code, clang, gcc, git, platform IO and all that. Make my dev env.. Finally, I will image a new copy of that disk to my PC. That will become my gold copy. If anything blows up, I just start over. All my source gets checked in routinely to github. It's not really an issue.
C) I'm not just going to throw away $35 without seeing if it was money well spent or not
That's why I say I don't care. The 512GB was me going "how can i make sure i'll never have to waste time worrying about space on this thing?"
Real programmers use butterflies
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Fair enough. 
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I'd be cautious about using an expensive SD card in the pi, they can be damaged by powering off while being written to. I've had a few fail completely.
So I'd go for having a couple of smaller/cheaper cards, rather than one big expensive one.
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I would avoid booting from SD cards. They are prone to failure (and usually at the worst possible time). Boot from a quality 16GB thumb drive (I use Samsung Fit+ drives), and if you need the extra storage, simply connect a SSD to one of the other USB ports.
Am I correct in assuming that you got a Pi4 with > 2GB RAM?
I would consider running POE because the USB-C power connection is not at all reliable if you start moving the pi around. You want to avoid uncontrolled power-down events - ESPECIALLY if you're booting from a SD card.
I've found that the Pi4 runs very hot. Get a good cooling solution. The best one available is the Ice Tower. I use that one exclusively. Ice Tower case with Low-profile cooler[^]. You can also get just the cooler if you have other needs like I do.
If you're decide to do POE, I recommend the UCTronics POE hat. I had to order mine direct from UCTronics because I couldn't find it on Amazon.UCTRONICS PoE HAT 5V 3A for Raspberry Pi 4B, 3B+ and 802.3af/at PoE Network, with Cooling Fan[^]
I also got their HDMI extender: UCTRONICS Micro HDMI to HDMI Adapter Board for Raspberry Pi 4 Model B[^]
As well as their rack mounting plate (because it provides a mount point for the HDMI extender board): UCTRONICS Mounting Plates for Raspberry Pi 4 B Models, Compatible with 19 inch 3U Rack Mount, 4-Pack[^] - this comes in a pack of four, but I have seven Pi's and got two of these four-packs.
POE Consideration - the UCTronics POE hat precludes the use of any viable cooling solution if you mount it as intended (directly on the GPIO pins). Because I insist on running the Ice Tower cooler (cited above), I had to cobble together a solution that did the following:
0) an adapter for the GPIO pins on the pi that essentially made a "T" that allowed me to connect the POE hat with a ribbon cable, and still allowed me access to the GPIO pins to connect the fan on the ice tower - GPIO 1 to 2 Expansion Board 2 x 20-pin Strip Dual Male Header Double Row Straight GPIO Connector Pin Header[^]
1) I got some 200mm male-female jumper cables to connect the POE header on the pi to the POE hat - Jumper cables[^]
2) I got a 200mm 40-pin ribbon cable to connect the pi GPIO pins to the POE hat - Adafruit ruibbon cable[^]
3) I got a 90-degree GPIO male-to-female adapter to connect the ribbon cable to the POE hat. The reason for this is that a standard male ribbon cable connector will interfere with the 4-pin connector on the POE had - uxcell 9Pcs 2x20 Pin Box Header Connector IDC Male Sockets Right Angle 2.54mm [^]
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I know this all sounds kinda convoluted, but POE is necessary in my use case, and the Ice Tower cooler is a highly valued cooling solution. I'm currently designing a case to hold it all. When I get done, and if you have access to a 3D printer, I can share the design with you.
".45 ACP - because shooting twice is just silly" - JSOP, 2010
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You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010
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When you pry the gun from my cold dead hands, be careful - the barrel will be very hot. - JSOP, 2013
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Thanks for all that information. I got a starter kit that includes a case and a couple of fans.
I have a powered USB hub. I'd bet you good money your USB power problems were from trying drive your pi off of the PC's USB power directly. I'll give that a go for a little while and see how it goes.
I'd have loved to know about your issues with SSD before I went and bought half a terabyte of it. 
I'll be hooking it into my main monitor and using a full size keyboard with it since it is being used as a development machine for reasons - that's why I bought it. It has 8GB.
I'll back my SD up after every session. And in any case I use source control. Since this machine is purely to speed up my development of drivers for i2c and spi devices all I'm doing with it is coding.
Real programmers use butterflies
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honey the codewitch wrote: I'd bet you good money your USB power problems were from trying drive your pi off of the PC's USB power directly.
I was actually talking about the physical connector, but before I switched over to POE, all of my Pi's were powered from a wall-wart.
honey the codewitch wrote: I'd have loved to know about your issues with SSD before I went and bought half a terabyte of it.
The SD card unreliability is kinda widely known, especially among Pi owners.
BTW, ALWAYS do a controlled shutdown/power-off. Never just shut it off, especially if you're using a SD card to boot from.
One more thing - if you do change to booting from a thumb drive, it's a good idea to keep an unformatted 1gb (or smaller) SD card in the SD slot. It speeds booting from the thmb drive, and keeps the Pi from periodically polling the SD slot to see if a card is in it.
".45 ACP - because shooting twice is just silly" - JSOP, 2010
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You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010
-----
When you pry the gun from my cold dead hands, be careful - the barrel will be very hot. - JSOP, 2013
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Thanks. The SD i ordered was sold out anyway, So i didn't end up getting it. I'm glad. I'll end up ordering a thumb drive.
Real programmers use butterflies
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As JSOP said they do run hot, on mine I put heat sinks and put it in a case with a fan.
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Are you sure this purchase is not a result of circular reasoning?
| Ravings en masse^ |
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| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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Pi shaped reasoning, so yes I suppose =)
Real programmers use butterflies
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Given your hardware constraints, would a limited set of named colors be useful [^]
Off-topic: It might interest you to explore Pantone (subtractive) colors: [^], [^]
«One day it will have to be officially admitted that what we have christened reality is an even greater illusion than the world of dreams.» Salvador Dali
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The way C++ works none of the colors are instantiated unless you use them. Strings ... that's not *as* true, so I'm wary of strings. Basically, until I can find a use case for having an actual string in the code for a color name, I'm going to avoid it.
All of the X11 colors I declared are good because like I said, they are only instantiated in the final binary if they are used, and even then they are represented by a single machine word.
The subtractive color models like CYMk? I can support those, I just have nothing that uses them yet so I haven't created a pixel with those channels.
This library will support pretty much any color model, with the possible exception of color models that are dependent on spatial positioning.
Real programmers use butterflies
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