ARMing a Breadboard – Everyone Should Program an ARM • Hacker News Board

Re: ARMing a Breadboard – Everyone Should Program an ARM

#41

Post by userbinator » Sat, Oct 10, 2015, 4:41 PM UTC

0xcde4c3db wrote: post #10

If you're interested in low-level code (assembly, JITs, Forth, etc.), note that official documentation for the ARM ISA has considerable encumbrance. It's not like most architectures where you just go to the manufacturer's website and download a PDF of the programming manual; ARM makes you register an account and agree to a rather restrictive clickwrap license (something to the effect of "you're only allowed to use th…

or maybe people just punch "ARM Architecture Reference Manual" into Google and grab one of the many slightly-outdated copies that are floating around on .edu servers

That's what everyone does, and AFAIK the ARM ISA documentation is public. The lower-level details to do with the core hardware itself/how to synthesise the core are NDA'd, however.

Re: ARMing a Breadboard – Everyone Should Program an ARM

#42

Post by Sanddancer » Sat, Oct 10, 2015, 4:42 PM UTC

the-dude wrote: post #27

ChuckMcM wrote: post #13

I too am often surprised at how often people reach for an Atmel 8 bit AVR chip rather than an ARM. It is a testament to the momentum that Atmel built, the avr-freaks community and the amazing cost effectiveness of it all. But now we're seeing ARM chips with built in clocks, and fewer base components required and I think the end of that AVR dominance is on the horizon. And that is why Dialog is buying Atmel[1]. Gettin…

With a development board: yes. But if you want to do hack something on a breadboard or make your own PCB it is really convenient to have THD ( through hole device ). The ARM used in the article is the only TDH available AFAIK.

NXP makes a smaller LPC that's also PTH, the LPC810. It's only 8 pins, but it looks a lot sexier for certain designs than the ol' standby ATtiny85, because it's got things like built-in i2c.

Oh, and with a mild amount of bravery, soldering SMD components isn't that difficult. A cheap toaster oven that you know damn well will never ever ever be used for making food again can do a decent enough job of doing the reflow for you.

Re: ARMing a Breadboard – Everyone Should Program an ARM

#43

Post by userbinator » Sat, Oct 10, 2015, 4:45 PM UTC

ChuckMcM wrote: post #13

I too am often surprised at how often people reach for an Atmel 8 bit AVR chip rather than an ARM. It is a testament to the momentum that Atmel built, the avr-freaks community and the amazing cost effectiveness of it all. But now we're seeing ARM chips with built in clocks, and fewer base components required and I think the end of that AVR dominance is on the horizon. And that is why Dialog is buying Atmel[1]. Gettin…

My go-to for applications that don't need more than an 8-bit MCU is PIC and 8051. Quirky architectures, but they're also cheaper in large quantities.

Re: ARMing a Breadboard – Everyone Should Program an ARM

#44

Post by aexaey » Sat, Oct 10, 2015, 4:48 PM UTC

ChuckMcM wrote: post #39

klagermkii wrote: post #31

Earlier quoted context omitted.

Most hobby electronics projects aren't really CPU limited though, so using ARM doesn't really bring relevant advantages. Having a standard platform, including the peripherals like PWM/ADC/timer etc which are going to vary wildly between ARM implementations, is far more important for people starting out and are trying to solve their problems via Google. The 5V chips are also better at taking punches from miswired proj…

My experience is that most hobby projects are RAM limited when people are using the AVR chips. Whether its trying to hold a copy of an LCD view, or any sort of moderate data structure. The ATMega328 is 8K of RAM. The M0+ chips seems to all come with 64K of RAM, and given that folks are writing in C/C++ rather than Assembler that is quite helpful. I agree with you on the general tolerances to abuse though. I've filled…

> The ATMega328 is 8K of RAM

No, just 2K. [0]

> The M0+ chips seems to all come with 64K of RAM

That would be 8K. [1]

[0] http://www.atmel.com/devices/atmega328.aspx

[1] http://www.st.com/web/en/catalog/mmc/FM141/SC1169/SS1817?sc=...

Re: ARMing a Breadboard – Everyone Should Program an ARM

#45

Post by 0xcde4c3db » Sat, Oct 10, 2015, 4:50 PM UTC

pcwalton wrote: post #37

0xcde4c3db wrote: post #10

If you're interested in low-level code (assembly, JITs, Forth, etc.), note that official documentation for the ARM ISA has considerable encumbrance. It's not like most architectures where you just go to the manufacturer's website and download a PDF of the programming manual; ARM makes you register an account and agree to a rather restrictive clickwrap license (something to the effect of "you're only allowed to use th…

The situation still isn't great, but this has gotten better over time with the documentation on infocenter.arm.com, which Google usually pulls up as a top result when you search for various ARM instructions. For example, Googling for "arm tbl" brings up this: http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.... which contains links to the rest of the AArch64 instruction set. The documentation has scary "Su…

That's good to know. I hope it's a sign of things to come. I've been hoping for RISC-V to take off, but even being optimistic, that's probably 3+ years from being orderable on Digi-Key.

Re: ARMing a Breadboard – Everyone Should Program an ARM

#46

Post by Sanddancer » Sat, Oct 10, 2015, 4:53 PM UTC

ChuckMcM wrote: post #13

I too am often surprised at how often people reach for an Atmel 8 bit AVR chip rather than an ARM. It is a testament to the momentum that Atmel built, the avr-freaks community and the amazing cost effectiveness of it all. But now we're seeing ARM chips with built in clocks, and fewer base components required and I think the end of that AVR dominance is on the horizon. And that is why Dialog is buying Atmel[1]. Gettin…

For your i2c issue, the translation circuit is just a couple MOSFETs and ensuring both sides of the converter have their pull-ups.[1] Bit annoying when you're dealing with the circuit, but there are worse problems to be had.

[1] http://playground.arduino.cc/Main/I2CBi-directionalLevelShif...

Re: ARMing a Breadboard – Everyone Should Program an ARM

#47

Post by Sanddancer » Sat, Oct 10, 2015, 4:54 PM UTC

vvanders wrote: post #29

ChuckMcM wrote: post #13

I too am often surprised at how often people reach for an Atmel 8 bit AVR chip rather than an ARM. It is a testament to the momentum that Atmel built, the avr-freaks community and the amazing cost effectiveness of it all. But now we're seeing ARM chips with built in clocks, and fewer base components required and I think the end of that AVR dominance is on the horizon. And that is why Dialog is buying Atmel[1]. Gettin…

Avr devtools are also fantastic since they licensed the Visual Studio shell.

Very much yes, if for no other reason than their automagic conversion of . to -> as needed for classes. It's a tiny thing, but when you're dereferencing a lot of classes, needing to hit one convenient button is nicer than three.

Re: ARMing a Breadboard – Everyone Should Program an ARM

#48

Post by ChuckMcM » Sat, Oct 10, 2015, 5:03 PM UTC

Sanddancer wrote: post #46

ChuckMcM wrote: post #13

I too am often surprised at how often people reach for an Atmel 8 bit AVR chip rather than an ARM. It is a testament to the momentum that Atmel built, the avr-freaks community and the amazing cost effectiveness of it all. But now we're seeing ARM chips with built in clocks, and fewer base components required and I think the end of that AVR dominance is on the horizon. And that is why Dialog is buying Atmel[1]. Gettin…

For your i2c issue, the translation circuit is just a couple MOSFETs and ensuring both sides of the converter have their pull-ups.[1] Bit annoying when you're dealing with the circuit, but there are worse problems to be had. [1] http://playground.arduino.cc/Main/I2CBi-directionalLevelShif...

That it a good solution, and in the case of the ST Micro chips the i2c lines can be pulled to 5V without issue, but in terms of compatibility Arduino shields which use i2c rarely pull them to 5V with weak pullups, expecting you to do that with the chip instead.

Re: ARMing a Breadboard – Everyone Should Program an ARM

#49

Post by ju-st » Sat, Oct 10, 2015, 5:07 PM UTC

kefka wrote: post #25

ju-st wrote: post #19

You can buy Arduinos on Aliexpress for USD1.80[1] and there are no comparable offers for ARM boards. [1] aliexpress.com/item/Free-Shipping-Nano-3-0-Controller-Board-Compatible-with-Arduino-Nano-CH340-USB-Driver/2021663360.html

That's not true. They are just hidden. Stm8, $1.28 http://m.aliexpress.com/item/32351992629.html Stm32, $3.06 http://m.aliexpress.com/item/1568685935.html Edit: my phone did a stupid.

Nice! So there is basically no reason to buy Atmega anymore (for me, at least).

Re: ARMing a Breadboard – Everyone Should Program an ARM

#50

Post by kjs3 » Sat, Oct 10, 2015, 5:15 PM UTC

userbinator wrote: post #43

ChuckMcM wrote: post #13

I too am often surprised at how often people reach for an Atmel 8 bit AVR chip rather than an ARM. It is a testament to the momentum that Atmel built, the avr-freaks community and the amazing cost effectiveness of it all. But now we're seeing ARM chips with built in clocks, and fewer base components required and I think the end of that AVR dominance is on the horizon. And that is why Dialog is buying Atmel[1]. Gettin…

My go-to for applications that don't need more than an 8-bit MCU is PIC and 8051. Quirky architectures, but they're also cheaper in large quantities.

I use 8051 for anything I do 8-bit as well. There are an almost infinite variety of speed/memory/peripheral combos available, still comes in hobby-friendly packages, and vast libraries of code and solid dev tools.

Never could stomach PIC. 8051 is 'quirky'; PIC is 'wtf?'. YMMV.