Difference between revisions of "Microcontrollers-What's Out There"
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===[http://www.microchip.com PIC] === | ===[http://www.microchip.com PIC] === | ||
*Excellent general purpose chips | *Excellent general purpose chips | ||
+ | |||
+ | The Microchip PIC microcontrollers were perhaps the first that were marketed to the hobbyist and student community, one of the first microcontrollers to be offered in a relatively small package (18 pin DIP) and one of the first to implement flash or eeprom program memory (in the PIC16C84 in 1993) | ||
+ | |||
+ | Architecture: harvard, accumulator based (mostly) | ||
+ | Package sizes: 6, 8, 14, 18, 20, 28, 40, ... 100 | ||
+ | Program memory size: 256 words (12bit words = one instruction) to 256k bytes (2 bytes=1 instruction) | ||
+ | Data RAM: 16 to ~3900 bytes (4096 byte address space, shared with peripheral registers.) | ||
+ | Special features: EEPROM, 20mA output drive, several "sub-architectures" | ||
+ | |||
+ | Flash memory based PIC microcontrollers curently range from vanishingly small 6-pin chips in SOT23 packages to 100pin TQFPs. The basic architecture has been extended to chips with 16bit ALUs and integral DSP functionality. | ||
+ | |||
+ | Microchip has a liberal sample policy and chips are widely available from many vendors. | ||
+ | |||
+ | ==Features== | ||
*18 - 28 pin packages (down to 8) with 14-22 I/O | *18 - 28 pin packages (down to 8) with 14-22 I/O | ||
*ADC available, usually 4 channels, 8 bits | *ADC available, usually 4 channels, 8 bits |
Revision as of 15:25, 15 March 2009
Contents
Families of Microcontrollers
PIC
- Excellent general purpose chips
The Microchip PIC microcontrollers were perhaps the first that were marketed to the hobbyist and student community, one of the first microcontrollers to be offered in a relatively small package (18 pin DIP) and one of the first to implement flash or eeprom program memory (in the PIC16C84 in 1993)
Architecture: harvard, accumulator based (mostly) Package sizes: 6, 8, 14, 18, 20, 28, 40, ... 100 Program memory size: 256 words (12bit words = one instruction) to 256k bytes (2 bytes=1 instruction) Data RAM: 16 to ~3900 bytes (4096 byte address space, shared with peripheral registers.) Special features: EEPROM, 20mA output drive, several "sub-architectures"
Flash memory based PIC microcontrollers curently range from vanishingly small 6-pin chips in SOT23 packages to 100pin TQFPs. The basic architecture has been extended to chips with 16bit ALUs and integral DSP functionality.
Microchip has a liberal sample policy and chips are widely available from many vendors.
Features
- 18 - 28 pin packages (down to 8) with 14-22 I/O
- ADC available, usually 4 channels, 8 bits
- Max. 5 MIPS
- Hardware UART on heavier chips
- No external addressing
SH1 - Hitachi SH Family
- Speed (20 MIPS)
- Bits (32)
- RAM (8K)
- 16 bit timers (5)
- Interrupts (40)
- Power drain (100 mA)
- Pins to solder (100)
ADuC812
- Good for data collection, smart sensor type application
- Fast (5 us) 8 channel, 12 bit ADC
- Hardware UART
- Flash
- CISC
- 1.25 MIPS max
68HC11
- 8 channel, 8 bit ADC
- 20K program, 1K RAM
- 5 16-bit timers
- 38 I/O pins
- UART
- 24 bit external memory space
- But: 3 MHz clock
Links
- Wikipedia article: http://en.wikipedia.org/wiki/Microcontroller
- Microcontroller Interfacing Laboratory at North Dakota State: http://www.ece.ndsu.nodak.edu/~tareski/pub/sccs98.htm
- Selecting Microcontrollers - Blog: http://www.8051projects.info/blogs.asp?view=plink&id=132
- Selecting Microcontrollers - Evil Mad Scientist!: http://www.evilmadscientist.com/article.php/mcus
- MIT Microcontroller Overview Lecture Notes - http://www.media.mit.edu/physics/pedagogy/fab/ucntrl/fabmicronotes.html