25 octobre 2009

ATxmega




I received the new processor that may well be the basis of the next version of RCHome. It is an atXmega192A3. This processor looks very interesting for a radio transmitter because it has:
* 16 Kbyte SRAM, which gives more spaces for the core of the software,
* ADC 12bits (Analog to Digital) converter: for a best accuracy of stick inputs
* tqfp 64 package, is "smt" technology, but should be still reasonable to solder,
* has hardware support for quadratic encoders,
* many IO pins (switch, several rotary encoder, lcd, etc...)
* several timers
* 32 Mhz clock

But it has some drawbacks also:
* can't be programmed with ISP, need PDI and there is still no low cost PDI programmer
* programmatic interface a bit different from Atmega AVR
* requires most recent version of avr-gcc tools
* has still few concrete examples on how to use

Here is the adaptor board for the stk600, I should receive the stk600 soon.

2 commentaires:

Jan a dit…

Don't you think you are taking a wrong turn here with your project? i mean RC hobby and microcontroller are already a small niche, with limited people. now making it even harder to participate by introducing smt, 500 Dollar Programmer and new IDEs...

no offence, it't your (amazing) project, just giving your a thought or two about accessibility...

Olivier Bordes a dit…

Dear Jan,
Thanks for your interesting comment. I don't feel Xmega as a a complete turn. Yes, the Xmega is a TQFP64 case SMT and more difficult to solver than 644 DIP. But other components on boards may not need to be SMT and can stay simple, the same way as it is currently done for the 644. For the programming, only bootloader is needed to be flashed. In a first step, I will propose to flash the bootloader. I also guess that soon, there will be low cost PDI programmer. Atmega644 is fine for small radios with basic capability, but has too many limitations for bigger radios.