Download Electrical parameters of microcontrollers 8051 family

Advanced Microcontrollers
Grzegorz Budzyń
Lecture 3:
Electrical parameters of microcontrollers
8051 family
Plan
• Electrical parameters of microcontrollers
• 8051 core (8-bit)
– Main features
– 8051 based microcontrollers
Electrical parameters
Electrical parameters
• Important parameters:
– Maximum ratings
– Power supply:
• Voltage
• Current consumption
– Clocking
– Reset
– I/O ports parameters
Electrical parameters
Maximum ratings
Maximum ratings
• Microcontrollers have to be viewed as a
complicated device, sensitive to many factors
• Each device have their own Absolute
Maximum Ratings that must be viewed very
carefully
• The values found in that table MUST NOT be
exceeded
Maximum ratings
• Main parameters:
– Operating temperature
•
•
•
•
Usually from -40C to 130C
Differs from chip vendor to chip vendor
Usually different temperature versions available
Thermal resistance should be taken into consideration
in order to avoid problems with overheating
• Microcontrollers are usually NOT protected against
overheating!
Maximum ratings
• Main parameters:
– Maximum operating voltage:
• Maximum value of voltage that can be connected to
power supply input of the microcontroller
• For microcontrollers with multiple power supplies
inputs, the maximum operating voltage is defined for
each input separately
Maximum ratings
• Main parameters:
– Input / output voltage range:
• Maximum value of voltage that can be connected to
any pin of the microcontroller
• The value is usually limitted by the actual power supply
value and may stay within some limits (i.e. -0.5V to
VCC+0.5V)
• The input-output voltage range can be extended when
the CLAMP CURRENT parameter is used properly
Maximum ratings
• Main parameters:
– Clamp Current:
• The maximum current that the input can sink or the
output can source without any damage
• Usually in mA range
• If a series resistor is used then even very high or
negative voltages can be directly connected to the
microcontroller
• Usable in ESD protection
Electrical parameters
Power supply
Power supply
• Delivering power to microcontrollers is usually
a delicate task
• Most of microcontrollers have more than 1
power supply input
• Each power supply input have usually
different requirements
• The most problematic for proper power
supply are microcontrollers with analog part
Power supply
Single supply
Dual supply
System grounding
Grounds
shortened only
on uC
Ground shortened
only on power
supply
Grounds
shortened only
on uC
Current consumption
• The requirements on power consumption
reduction are nowdays very high
• The active supply current is in the range of
1mA/MIPS
• The active supply current depends on the
main clock frequency
• Microcontrollers offer many supply modes in
order to reduce power consumption
Current consumption
Electrical parameters
Clocking
Clocking
• External Crystal Oscillator:
– An external crystal oscillator is connected
between XTAL inputs
– Modifying clock frequency requires change of the
physical object (crystal)
– Clock stability can be high (1-10ppm)
Clocking
• Low Frequency Crystal Oscillator:
– Optimised for low frequency crystals – mainly the
32.768 kHz
– Similar stability like standard Crystal Oscillator
Clocking
• External RC Oscillator:
– Very simple and cheap option
– Just two discreet components necessary
– Limited to a few MHz range
– Ease of frequency regulation
– Very low stability (100-1000 ppm)
Clocking
• Internal RC Oscillator:
– Very simple and cheap option
– Limited to a few MHz range
– Ease of frequency regulation – only software
register change necessary
– Possibility of frequency calibration
– Very low stability (100-1000 ppm)
Clocking
• External Clock:
– The most expensive option
– Just one (but complicated!) component necessary – the
clock generator
– Very wide frequency range available (even above 100MHz)
– No possiblity of frequency regulation
– High to Ultra high stability (0.000001 - 10 ppm)!!!
Clocking
• Internal PLL:
– Requires external clock or external oscillator
– Wide frequency range available
– Ease of frequency regulation via software register
– Stability depends on the clock source and the
jitter of PLL. Usually not better than 1ppm
Electrical parameters
Reset
Reset
• During Reset:
– all I/O Registers are set to their initial values
– the program starts execution from the Reset
Vector
• The reset circuitry does not require any clock
source to be running (it is asynchronous)
Reset
• In most microcontrollers there are available a few
reset sources:
– Power-on Reset. The MCU is reset when the supply
voltage is below the Power-on Reset threshold (VPOT)
– External Reset. The MCU is reset when a low level is
present on the RESET pin for longer than the minimum
pulse length
– Watchdog Reset. The MCU is reset when the Watchdog
Timer period expires and the Watchdog is enabled
– Brown-out Reset. The MCU is reset when the supply
voltage VCC is below the Brown-out Reset threshold
(VBOT) and the Brown-out Detector is enabled
Power-on Reset
External Reset
Brown-out Reset
Watchdog Reset
Electrical parameters
I/O ports
General I/O port structure
I/O port with internal pull-up
I/O port with push-pull
Introduction - 8051
Introduction
• Family of 8051 originates from Intel8051
microcontroller constructed in 1980
• 8051 microcontrollers were, for the long time,
the most popular microcontrollers on the
market
Introduction
• One of the source of success is the fact that
8051 base microcontrollers are offered by
many vendors (e.g. Siemens, Infineon, Atmel,
Philips, Dallas Semiconductors, Analog
Devices)
• 8051 based microcontrollers are still very
popular because of backward compatibility
and because present constructions are much
more efficient than original ones
Introduction – block diagram
External interrupts
Interrupt
Control
On-chip
ROM for
program
code
Timer/Counter
On-chip
RAM
Timer 1
Timer 0
CPU
OSC
Bus
Control
4 I/O Ports
P0 P1 P2 P3
Address/Data
Serial
Port
TxD RxD
Counter
Inputs
Introduction - Architecture
• Main features:
– 8-bit CISC processor
– Modified Harvard architecture (instructions and
data on separate busses)
– 4 banks of 8 x 8b universal registers
– Instructions executed in 1, 2 or 3 instruction clock
cycles (12 clock pulses)
Introduction - Architecture
• Main features:
–
–
–
–
–
–
4kB of internal ROM
128B of internal SRAM
four parallel ports P0..P3
1 x UART
Two timers (one used for UART transmission)
interrupt subsystem with priorities
Source: [1]
PIC10
Source: [1]
8051 - pinout
8051 - pinout
• Main pins:
– RST – active high
– EA – External Access – logic „0” means execution
of program from internal ROM
– PSEN - Program Store Enable – OE for external
memory
– ALE - Address Latch Enable – signal used for
demultiplexing of data and address
8051 - registers
A
B
R0
DPTR
DPH
DPL
R2
PC
PC
R3
R4
R5
R6
R7
Some 8-bitt Registers of
the 8051
Some 8051 16-bit Register
Source: [1]
R1
8051 – Main producers
ChipCON (TI) – versions with internal wireless
communications blocks
Analog Devices – very good „Analog
microcontrollers” with embedded, high-quality,
analog-digital and digital-analog converters
8051 – Main producers
Dallas Semiconductors – very high performance
(33MIPS in comparison to original 1MIPS!!!);
excellent communication blocks (CAN, Ethernet)
NXP – a lot of „classical” models, power supply
current reduction, improved performance
8051 by ChipCON (TI)
Source: [2]
8051 by ChipCON
CC2430
• Main features:
– SoC chip – integrated processor and RF circuits
– 8051 CPU, 32MHz
– 8kB of SRAM
– 128kB Flash
– RF 2.4GHz, 802.15.4 transceiver
– Low supply voltage
– Very small component count
Source: [3]
CC2430
8051 by Analog Devices
PIC12F615 – block diagram
ADuC 824
• Named „Analog microcontroller”:
– Main part are precision ADC’s and DAC’s
– Microprocessor is only an addition
• Fully integrated 24-bit data acquisition system
• Software compatible with 8052 processors
Source: [4]
ADuC 824
ADuC 824
• Main features:
– High Resolution Sigma-Delta ADCs
•
•
•
•
•
Two Independent ADCs (16- and 24-Bit Resolution)
Programmable Gain Front End
24-Bit No Missing Codes, Primary ADC
13-Bit p-p Resolution @ 20 Hz, 20 mV Range
18-Bit p-p Resolution @ 20 Hz, 2.56 V Range
– Memory:
• 8kB Program Memory, 640 B Data Memory (Flash)
• 256B Data RAM
ADuC 824
• Main features:
– 8051-Based Core
•
•
•
•
•
8051-Compatible Instruction Set (12.58 MHz Max)
32 kHz External Crystal, On-Chip Programmable PLL
Three 16-Bit Timer/Counters
26 Programmable I/O Lines
11 Interrupt Sources, Two Priority Levels
– Power
• Specified for 3 V and 5 V Operation
• Normal: 3 mA @ 3 V (Core CLK = 1.5 MHz)
• Power-Down: 20 uA (32 kHz Crystal Running)
ADuC 824
• Main features:
– On-Chip Peripherals
•
•
•
•
•
•
•
•
On-Chip Temperature Sensor
12-Bit Voltage Output DAC
Dual Excitation Current Sources
Reference Detect Circuit
Time Interval Counter (TIC)
UART Serial I/O
I2C®-Compatible and SPI® Serial I/O
Watchdog Timer (WDT), Power Supply Monitor (PSM)
ADuC 824 – Main ADC structure
8051 by Dallas Semiconductors
Source: [5]
PIC12F615 – Pinout
Source: [5]
DS80C410
• 8-bit network microcontroller
• Many „connection” peripherals:
– 10/100 Mbs Ethernet
– 3 x serial ports
– CAN 2.0B controller
– 1-Wire Master
– 64kB SRAM for TCP/IP stack
Source: [6]
PIC16
DS80C410
• Main features:
– High-Performance Architecture
•
•
•
•
Single 8051 Instruction Cycle in 54ns
DC to 75MHz Clock Rate (1MIPS/4MHz)
Flat 16MB Address Space
Four Data Pointers with Auto-Increment/Decrement
and Select-Accelerate Data Movement
• 16/32-Bit Math Accelerator
DS80C410
• Multitiered Networking and I/O
– 10/100 Ethernet Media Access Controller (MAC)
– Optional CAN 2.0B Controller
– 1-Wire Net Controller
– Three Full-Duplex Hardware Serial Ports
– Up to Eight Bidirectional 8-Bit Ports (64 Digital I/O
Pins)
DS80C410
• Integrated Primary System Logic
– 16 Total Interrupt Sources with Six External
– Four 16-Bit Timer/Counters
– 2x/4x Clock Multiplier Reduces Electromagnetic
Interference (EMI)
– Programmable Watchdog Timer
– Oscillator-Fail Detection
– Programmable IrDA Clock
DS80C410
• Enhanced Memory Architecture
– Selectable 8/10-Bit Stack Pointer for High-Level Language
Support
– 64kBytes Additional On-Chip SRAM Usable as
Program/Data Memory
– 16-Bit/24-Bit Paged/24-Bit Contiguous Modes
– Selectable Multiplexed/Nonmultiplexed External Memory
Interface
– Merged Program/Data Memory Space Allows In-System
Programming
– Defaults to True 8051-Memory Compatibility
DS80C410 – External memory merging
Source: [6]
DS80C410 – arithemtic
coprocessor
DS80C410 – Ethernet
DS80C410 – ROM functions
• Plenty useful functions can be found in
DS80C410 ROM
• Many function categories, e.g.:
– Utility
– Memory managing
– Socket handling
– DHCP functions
– 1-Wire functions
– and many, many more….
DS80C410 – ROM functions
Thank you for your attention
References
[1] www.infineon.com
[2] www.ti.com
[3] CC2430 documentation; www.ti.com
[4] ADuC845 documentation; www.analog.com
[5] www.maxim-ic.com
[6] DS80C410 documentation; www.maxim-ic.com
[7]
http://www.ise.pw.edu.pl/impuls/emisy/80c517um.p
df
[8] http://www.atmel.com/images/doc2486.pdf