the Open Source hardware thread

OP
icebags

icebags

Technomancer
^ this is why i say start with the simplest. first get to know the simple ones, try with atmega. the programming manual is probably ~600 pages i heard (u dont everything, and neither u need to remember everything :D ) but u can still manage ur custom bootloader c program quite easily. i am looking forward to this as well, in very near future.

chip level programming those arm or higher end processors has to be quite a task to anybody. :-x
 
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Mr.Kickass

Mr.Kickass

In the zone
icebags said:
chip level programming...
Click to expand...

Chip level programming is basically treading into microelectronics territory so its all Verilog and VHDL

icebags said:
...those arm or higher end processors has to be quite a task to anybody. :-x
Click to expand...

Nah...many boards are based off ARM like your very own Beagleboard and Raspberry Pie. So, you indirectly work with ARM chips anyway.

If someone wants to just get inside this territory then this makes for a good noob friendly intro
ARM Basics
(Though you don't need it if you've already read the books mentioned, but still)

This document is a true hands-on introduction which one should read
ARM Cross Development with Eclipse

The Philips LPCxxx series is the most common way to get into ARM development. But what you are implying is the professional line of work. Even professionals work with the same devices albeit with a different objective and a lot more powerful set of tools. So, its not that high end of a device that we cannot mess with.

AFAIK its the DSP processors that are supposed to be for the academically inclined and not fit for general public consumption :-D

Now that would be serious task :twisted:
 
Mr.Kickass

Mr.Kickass

In the zone
So, I stayed up yesterday and somehow managed to get hold of an officially illegal legal source of the book which every newcomer should at least read once before starting out. The only con to this book is that it adopts Assembly and C as the language of instruction so those looking for coding in C++ using the Arduino IDE should simply skip it. The datasheet has all the relevant information about the controller.

I think the Arduino website is enough for getting started. Only those who wish to develop using tools provided by Atmel itself should bother reading the book. But this should be kept in mind that even the datasheet is biased towards using AVR suite which uses C (of course marketing, and why not)

This should be the starting point for anyone. Why ? Because this is what powers the Arduino Uno.
ATmega48A/PA/88A/PA/168A/PA/328/P Complete

You do not even need to read all of it(as not all of the features are required in building a system) but just complement it with a standard text like this
AVR Microcontroller and Embedded Systems.pdf

I hope the mods don't delete this link :Fingerx:

For those going the Arduino way, be sure to learn C++ very well and those going the AVR route should take the concept of bit manipulation seriously because programming in Arduino IDE is very very easy. You have a function for everything. There is a HUGE library at your disposal. Which is why its best for a newbie to start with that. Of course, it has its pitfall too. You cannot have low level control of hardware as you can have in AVR. But, in AVR you need to write a sub-routine even to take an input. In Arduino IDE its as easy as writing cin>> in C++ :D
 
OP
icebags

icebags

Technomancer
arrived my atmega328p with uno bootloader preloaded, from ebay (rs.~350/-). i connected it on a breadboad and led on pin 19 (pin 13 of a uno board) started blinking, seems they uploaded the blinky sketch on it too.

i am unable to upload a sketch myself, tried to interface it with com port via a max232 chip, but it could not communicate. multimeter shows when board is active usb voltage drops to ~4.25v, normally which i measured remains @ ~4.55v without load. max232 works @5v or may be 4.5v minimum, probably this is why. or may be my com port cable is too long. i need to see with a proper 5v source.

*i.imgur.com/HPjIpeb.jpg

also bought 2 blank atmega8s locally @ 65 -80rs. will try to upload stuff later onto them

*i.imgur.com/m1HX0U1.jpg
 
quagmire

quagmire

Allllright !
^*www.thinkdigit.com/forum/show-off/177167-my-raspberrypi.html
A quick search in the 'Post your latest Purchase' thread reveals d6bmg and nginx own a RasPi.


@icebags: Good to know people in TDF are into AVR development. :)

I bought an Atmega32 (40pin) for 190/- from SP Road, Bangalore.. Why did you pay so much for Atmega328?

Since you have a Atmega8 you can take a look at this : USBASP. Programmer for AVR uC..

I made the same a few days ago. Both on a perfboard and PCB :wink:. Works perfectly fine. (Better than max232 types..)
 
G

gopi_vbboy

Cyborg Agent
hi to @Kickass, @Icebags, @Quagmire and all

Started reading operating systems by william stalling..intresting till now.

Planning to buy beglebone or pi soon :)

--

I did quite research on beagleboard TI AM335x Datasheets and Uboot source code.

Have a few questions on beagleboard

1.Is Uboot/Any bootloader the only thing used to initialize the hardware in board?
Can we initialize hardware later in kernel space from linux?
Do we have to initialize them again from user space though drivers written inorder to use them?

2.I am just confused how hardware pins maps to registers and peripherals are initialized?
Are they done in user space or driver or bootloader?
When i compare with microcontroller i get confused.In microcntroller we only have a C language
code with infinite while(1){} loop.Before that Oscillators ,Ports ,peripherals are initialized.
Howz that done by Beagleboard and at what stage?

3.How does processor know that our Uboot binary is at particular SPI flash?
I mean how is the processor configured/initialized before loading boot-loader to ram i.e the moment we power on?

4.Why do we have some co processor in beaglebone?Is it to program the SPI flash though Serial/USB?

5.Is linux a generic kind of layer of code?I mean does it try to minimize board specific code like hardware initializations etc?
 
Mr.Kickass

Mr.Kickass

In the zone
icebags said:
^ interesting. but where to find a beaglebone black at suitable price ? saw one @ ebay @4.5k but is that a proper price ? raspberry seems a bit cheaper.
Click to expand...

Is this of any help ?
Besides, I'd prefer the BeagleBone

BeagleBone Black: A Maker’s Dream?
 
OP
icebags

icebags

Technomancer
quagmire said:
I bought an Atmega32 (40pin) for 190/- from SP Road, Bangalore.. Why did you pay so much for Atmega328?
Since you have a Atmega8 you can take a look at this : USBASP. Programmer for AVR uC..
I made the same a few days ago. Both on a perfboard and PCB :wink:. Works perfectly fine. (Better than max232 types..)
Click to expand...

i asked local shops for 328, they were saying ~300, so just thought of buying one with bootloader at some extra price, to escape the process of bootloading for the first time.

saw that usbasp link too, did not read details yet, but i would like to ask, how u loaded the usbasp firmware onto that atmega8 ? having an usbasp is a good idea, i read it can program sketches directly to chips, saving the bootloader space - good for standalone projects with atmega8s. :)
i am trying to use max232 for direct serial interfacing, for realtime arduino access, is it possible with usbasp ?

Mr.Kickass said:
Is this of any help ?
Besides, I'd prefer the BeagleBone

BeagleBone Black: A Maker’s Dream?
Click to expand...

thinking of making a query to borderless electronics if they are enthuciastic about launching a similar campain for beaglebone like they did with arduino. anyways, i will play with arduino for a while now.

gopi_vbboy said:
Started reading operating systems by william stalling..intresting till now.

Planning to buy beglebone or pi soon :)
Click to expand...

i have 0 beaglebone specific knowledge, only saw a few codes where they were using shell scripts to read/write data to pins, it appeared kinda similar to file programming to me. may be kickass will be able to help. :D

but this will probably be a good watch for u.

 
quagmire

quagmire

Allllright !
icebags said:
i asked local shops for 328, they were saying ~300, so just thought of buying one with bootloader at some extra price, to escape the process of bootloading for the first time.

saw that usbasp link too, did not read details yet, but i would like to ask, how u loaded the usbasp firmware onto that atmega8 ? having an usbasp is a good idea, i read it can program sketches directly to chips, saving the bootloader space - good for standalone projects with atmega8s. :)
i am trying to use max232 for direct serial interfacing, for realtime arduino access, is it possible with usbasp ?



thinking of making a query to borderless electronics if they are enthuciastic about launching a similar campain for beaglebone like they did with arduino. anyways, i will play with arduino for a while now.
Click to expand...

1.I have an Arduino Uno. I used it as a ISP (alongwith avrdude) and uploaded the firmware from the website.
2. Yes, you can simply connect MISO, MOSI, SCLK, VCC, GND from USBasp to target board and upload the hex file.
3. I am not sure. Also a disadvantage is that it is not supported by Atmel Studio, which gives you great tools for debugging..
4. Exactly. I'm dying to get my hands on a BeagleBone, but here the price from a authorised distributor is 4k :-(
 
Mr.Kickass

Mr.Kickass

In the zone
quagmire said:
4. Exactly. I'm dying to get my hands on a BeagleBone, but here the price from a authorised distributor is 4k :-(
Click to expand...

Get the new BeagleBone Black. It's cheaper than the 4K one

gopi_vbboy said:
hi to @Kickass, @Icebags, @Quagmire and all

Started reading operating systems by william stalling..intresting till now.
Click to expand...

Yep. That's the standard text. The very foundation
gopi_vbboy said:
Have a few questions on beagleboard
Click to expand...

^Beagleboard experts please...

IMO, you can ask in their forums as I'm sure they must be having an answer to that. And I'm yet to get a Beaglebone Black :p
 
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G

gopi_vbboy

Cyborg Agent
Hey guys just a query..45$ Beaglebone black is Rs 4490. .Do you think its a good deal? .. Is this imported or local manufactured?
BeagleBone Black. A Competitor to Raspberry Pi | eBay
 
amjath

amjath

Human Spambot
Make ur choices
BeagleBone Black vs. Raspberry Pi - Roboteurs
*makezine.com/magazine/how-to-choose-the-right-platform-raspberry-pi-or-beaglebone-black/
 
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