Appropriate microcontroller platform

[jhales71]

Hi

New to the group, my experience is missiles and RADAR so this is all new to me. I want to build an unmanned underwater vehicle with video, pressure and temperature feedback. I was thinking about six continuous rotation servos working in pairs for thrust in the X, Y and Z axis. With telemetry relayed via tether to a buoy and broadcasting short range via Wi-Fi or Bluetooth. My question is....what would be an appropriate microcontroller platform?

Regards,

Jeff

[z.s.tar.gz]

I personally prefer AVR based microcontrollers. Especially the atmega's.
If you need a lot of I/O and want to use though-hole, it doesn't get better than the atmega644.

[SmAsH]

The axon/axon 2 could do what you are wanting, it has all the i/o and cant connect to bluetooth/wireless easily.

[jhales71]

Thanks for your help.

So a short list of an Axon II or an AVR like maybe an Arduino Mega. Has anyonedone a direct comparison between the two MCU's? Or is it all down to personal preference?

Best regards,

Jeff

[Joker94]

well axon is the crem de le crem (the best you can get) and has alot more options when things get more complicated/advanced.

you just have to compare the features you need and want vs the microcontrollers capabilities and features. And also how much your willing to pay.

There is also this one which i have recently bought http://www.yerobot.com/romeo-all-in-one-arduino-controller.html

it has alot of good features and it is really good value.

[Razor Concepts]

There are also PIC microcontrollers, they are on the same level as AVRs (but on this forum AVRs are more popular).

And if you are experienced in coding, you could look into ARM Cortex-M3 microcontrollers. If AVRs and PICs are like bicycles, the the Cortex-m3 is a Corvette.

[z.s.tar.gz]

AVR based ones will be less expensive than Axon's, but if you needed a powerful avr based MCU already put together, the Axon is the way to go.

[rgcustodio]

AVR based ones will be less expensive than Axon's, but if you needed a powerful avr based MCU already put together, the Axon is the way to go.

The Axon and Axon II is powered by an AVR 8-bit RISC MCU.


The Cortex series is good, but the ARM9/ARM11 core is better. Well, we could go on and on and on.

The main limitations of all the MCUs mentioned are memory (flash andRAM), and GP I/O (DAC, ADC channels, etc).
You can add some RAM (not EEPROM) to these MCUs but at the expense of I/O pins. Such is the world of embedded systems.

Best bang for the buck are the ARM processors.
- they are clocked fast (certainly faster than 16Mhz, I have an LPC2388 here clocked at 72MHz, another ARM9 clocked at 200MHz)
- have built in controllers for various peripherals (USB, SPI, LIN, CAN, MMIO, MAC, many other 3-letter abbreviated protocol, etc, etc)
- more built-in RAM/Flash than AVRs (almost 2x of AVR, ARM9 has MMU allowing you to connect a memory controller that can control DDR RAM)
- have more than 50 general purpose I/O pins
- 32-bits comes in handy most of the times (specially timers)
- mature toolchains readily available (Codesourcery for baremetal toolchains)
- ARM9 features data and instruction caches (better performance)
- has 16-bit instruction set (Thumb), in case you want to lessen the code size at the expense of execution speed

We can continue to discuss all of the good features of many MCUs but I guess it all depends on how much you want to spend, how knowledgeable you are with programming (and H/W interfacing), what features you want to use, and what other feature you may want to use in the future (expansion).

Goodluck.