Now that Sparkfun offers the 32-bit Maple, I’d like to see the Maple Mini offered at Sparkfun. I prefer shopping at one place to save shipping & handling (and buy more Sparkfun goodies). In my humble opinion, its likely the best 32-bit microcontroller programmable in C on a 40-pin “stamp” for a breadboard. It features a 32-bit ARM Cortex STM processor, 72Mhz, 120KB of flash, 20KB of SRAM, its got 12 PWM outputs (16-bit), 9 ADCs (12-bit!!!), 4 timers, 2 SPI ports, and 3 USARTs (not much to say about the two I2Cs). Regular price is $34.99! That is the most bang for the buck. By the time your read this, the special price of $24.99 for the first 100 modules will be gone.
Not sure why anyone would buy a Basic Stamp for $49.95 for a 24-pin module, 2KB of flash, only 32 bytes of RAM (that’s right, 0.032KB), and no ADCs! Just so you know, I’m not a Leaflabs representative, I’m just a Sparkfun customer sharing tips on promising products. Check for yourself.
liam.sparkfun:
Not that Sparkfun offers the 32-bit Maple, I’d like to see the Maple Mini offered at Sparkfun. I prefer shopping at one place to save shipping & handling (and buy more Sparkfun goodies). In my humble opinion, its likely the best 32-bit microcontroller programmable in C on a 40-pin “stamp” for a breadboard. It features a 32-bit ARM Cortex STM processor, 72Mhz, 120KB of flash, 20KB of SRAM, its got 12 PWM outputs (16-bit), 9 ADCs (12-bit!!!), 4 timers, 2 SPI ports, and 3 USARTs (not much to say about the two I2Cs). Regular price is $34.99! That is the most bang for the buck. By the time your read this, the special price of $24.99 for the first 100 modules will be gone.
Not sure why anyone would buy a Basic Stamp for $49.95 for a 24-pin module, 2KB of flash, only 32 bytes of RAM (that’s right, 0.032KB), and no ADCs! Just so you know, I’m not a Leaflabs representative, I’m just a Sparkfun customer sharing tips on promising products. Check for yourself.
The ST VL Discovery is a small development board that sells for <$12. It has the features that you mentioned and includes a full JTAG/SWD programmer/debugger on the board plus it has a 2-channel 12-bit DAC module (something you won't find anywhere else, especially at this price) to boot. It can be used with any any tool chain that supports the STM32.
Good point on the Discovery board. Although its priced at only $12 dollars, its not an Arduino-compatible module programmable through a simple USB connection. With Discovery, you need a programmer, a compiler, an understanding of low-level programming, and lots of free time. That’s why I like Arduino, Zbasic, Picaxe, etc. - they free from all that low-level complexity. Anyway, $35 for a 32-bit Maple Mini with a breadboardable format is an excellent deal. Please see my comparison list below. The Coridium ProPlus is the same price, but is not breadboardable and has 3 less ADCs, and their help/forum is lackluster. The FEZ products and Netduino do not interest me because of the programming language (C#), plus they waste so many processor i/o pins. Shameful.
Price Stamp ADC Code Model
---- ------- ------ ---- --------
$35* Yes/40p 9/12b C Maple Mini (http://forums.leaflabs.com/topic.php?id=251&page=2)
$39** Yes/40p 8/12b C/C++ Netburner 5213 (netburner.com/products/core_modules/mod5213.html)
$50 No 16/12b C Maple (http://leaflabs.com/)
$35 No 6/12b C Coridium PropPlus (coridiumcorp.com/PROplus.php)
$60 Yes/40p 6/12b C Mbed.org (www.mbed.org)
$59 Yes/24p 6/10b C Coridium ARMexpressLITE (coridiumcorp.com/ARMexpress.php)
$35 No 6/10b C# FEZ Panda (www.tinyclr.com/downloads/Panda/Broch_FEZ_Panda.pdf)
$35 No 6/10b C# Netduino (www.netduino.com/netduino/specs.htm)
$60 No 6/10b C# NetduinoPlus (www.netduino.com/netduinoplus/specs.htm)
* Currently selling at $25 as a promotion!
** Requires 1 development kit (+$60) for compiler and PC interface.
liam.sparkfun:
Although its priced at only $12 dollars, its not an Arduino-compatible module programmable through a simple USB connection. With Discovery, you need a programmer, a compiler, an understanding of low-level programming, and lots of free time. That’s why I like Arduino, Zbasic, Picaxe, etc. - they free from all that low-level complexity.
You do not need a programmer. As I mentioned, it comes with a built-in JTAG/SWD programmer/debugger (through a simple USB connection - in your words). The included (free) commercial grade compiler includes a source level breakpoint debugger, something which none of the systems you mentioned are capable of.
For me, I don’t care for low level programming, even if the compiler is free. On the other hand, $12 dollars for an assembled 32-bit Discovery is an excellent deal for those who don’t mind low level coding - it’d be nice if Sparkfun offered it too as an option.
leon - the Uno32 is an excellent value! The 32-bit wars are on! Too bad the ADC resolution is only 10bit. The Maple and Maple Mini feature 12bit ADC - this is very important for feedback control, especially for unstable systems (e.g., inverted pendulum). And too bad the Uno32 follows the Arduino form factor instead of a breadboardable format such as the 32-Bit Whacker below. Still, the Uno32 will be tough competition.
stevech:
The Maple Mini has only 120KB of flash. OK for fiddling, but that’s not much for a 32 bitter.
32-bit processors (such as the ARM Cortex-M3 STM32F103 in the Maple) offer superior code density to 8-bit and 16-bit architectures. This has significant advantages in terms of reduced memory requirements and maximizing the usage of on-chip Flash memory.
rmteo1 - your creedo “Why use 8 bits when you can have 32?” is very relevant.
I would further say “Why use 8 bits when you can have 32… at lower cost!”. The Uno32 and Maple Mini currently cost less than the 8-bit Basic Stamp and the Arduino Uno for much more capability.
liam.sparkfun:
…Too bad the ADC resolution is only 10bit. The Maple and Maple Mini feature 12bit ADC - this is very important for feedback control, especially for unstable systems (e.g., inverted pendulum).
The Freescale Kinetis MCU's (based on the ARM Cortex-M4 core with DSP) feature 16-bit ADCs. They also have 12-bit DACs (like the STM32F in the Maples) which AFAIK, none of the other manufacturers offer.
The Italian word for “two” is “due”. That’s the name of the upcoming 32bit Arduino module. It will likely be the best selling 32bit module ever and steam roll Maple, Maple Mini, Netduino, FEZ, Digilent ChipKit and Max32, etc… Digilent deserves a good steam rolling for their disingenuous claim of being the first 32bit module compatible with Arduino - that honor goes to Leaflabs Maple products. Still rooting for Leaflabs - their best strategy will be to remain Arduino compatible and continue to offer more capability at reduced cost.
liam.sparkfun:
Digilent deserves a good steam rolling for their disingenuous claim of being the first 32bit module compatible with Arduino - that honor goes to Leaflabs Maple products.
For any kind of serious development work, a hardware break-point debugger (incorporated into the IDE) is absolutely essential IMO. Does the Arduino (or similar) platform offer this functionality?
Good point regarding the Coridium ARMite Pro and the Arduino pin format. Its very likely it came before Maple, however the programming language departs further from Arduino than Maple.
A critical feature NOT in the Coridium ARMite Pro and Digilent Uno32 is 12bit ADC - they’re limited to 10bit ADC. Same holds true for FEZ, Netduino, and pretty much all modules featuring PIC chips.
For me, 12bit ADC is very important for feedback control systems. The 32bit Arduino Due does feature 12bit ADC. So do the Maple products, mbed.org, and Coridium PropPlus (pin count limited). We’ll see how much the Due costs. I may stay with Maple if the price exceeds $50.
stevech:
The Maple Mini has only 120KB of flash. OK for fiddling, but that’s not much for a 32 bitter.
I am developing the framework for an HMI (handheld terminal) that incorporates a 320x240 TFT LCD, membrane keypad (25 keys), USART comms, RTC, battery back-up, etc. The application has 9 concurrent tasks that are built upon an RTOS.
Currently it uses 13,128 bytes of FLASH and 880 bytes of RAM. In fact, the total memory used is small enough (14KB) to fit completely into RAM (my development MCU has 96K RAM). With the application in RAM, downloading during development is super fast and FLASH wear is eliminated. Also, with everything in RAM, you can have unlimited hardware breakpoints.
