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STH-11
ATMEL CORP
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STH-11 CONVERSION ROUTINE

                                    ;***************************************************************************
                                    ; 
                                    ; File Name		:'conv.asm"
                                    ; Title			:STH-11 konverzios rutinok
                                    ; Date			:2002.11.27.
                                    ; Version		:1.0.0
                                    ; Support telephone	:+36-70-333-4034 VFX
                                    ; Support fax		:
                                    ; Support Email		:info@vfx.hu
                                    ; Target MCU		:AT90S8515
                                    ; 
                                    ;***************************************************************************
                                    ;	D E S C R I P T I O N
                                    ;
                                    ;
                                    ;
                                    ;***************************************************************************
                                    ;	M O D I F I C A T I O N   H I S T O R Y 
                                    ;
                                    ;
                                    ;       rev.      date      who	  	why
                                    ;	----	----------  ---		------------------------------------
                                    ;	0.01	2002.11.27. VFX		Creation
                                    ;
                                    ;
                                    ;***************************************************************************
                                    
                                    ;**********************************************
                                    .DSEG
                                    Temperature:	.byte 2
                                    Humidity:	.byte 2
                                    
                                    
                                    
                                    .CSEG
                                    ;***************************************************************************
                                    ; Public Parts:
                                    ;
                                    ; CaltTemp - Homerseklet kiszamitasa  A valtozat
                                    ; Calc_Temp			      B valtozat
                                    ; CalcHum  - Paratartalom kiszamitasa
                                    ;
                                    ;***************************************************************************
                                    ;* Const Def
                                    ;
                                    ;
                                    ;
                                    ;
                                    ;**************************************************************************
                                    ;* Hardware Def.
                                    
                                    
                                    .include "mat32.asm"
                                    .include "8515DEF.INC"
                                    
                                    
                                    ;**************************************************************************
                                    ;** Homersekletet ASCIIban kiirja a ASCIIBuf-ba, 0-val lezarva
                                    ;
                                    PrintTemp:	lds	mant1,Temperature+0
                                    		lds	mant1m,Temperature+1
                                    		clr	mant1h
                                    		clr	mant1hh
                                    		rcall	ULTOA
                                    		ret
                                    
                                    
                                    ;**************************************************************************
                                    ;* Y = mx+b fugveny, konstansok a programmemoriaban m,b sorrenden
                                    ;* Z - konstans tabla elso eleme
                                    ;* ACC1 = eredmeny
                                    ;
                                    LinearF:	lpm
                                    		adiw	ZL,1
                                    		mov	mant2,R0
                                    		lpm
                                    		adiw	ZL,1
                                    		mov	mant2m,R0
                                    		lpm
                                    		adiw	ZL,1
                                    		mov	mant2h,R0
                                    		lpm
                                    		adiw	ZL,1
                                    		mov	mant2hh,R0
                                    		push	ZL
                                    		push	ZH
                                    		rcall	UMUL
                                    		pop	ZH
                                    		pop	ZL
                                    
                                    		lpm
                                    		adiw	ZL,1
                                    		mov	mant2,R0
                                    		lpm
                                    		adiw	ZL,1
                                    		mov	mant2m,R0
                                    		lpm
                                    		adiw	ZL,1
                                    		mov	mant2h,R0
                                    		lpm
                                    		adiw	ZL,1
                                    		mov	mant2hh,R0
                                    		push	ZL
                                    		push	ZH
                                    		rcall	ADD32
                                    		pop	ZH
                                    		pop	ZL
                                    		ret
                                    
                                    
                                    ;**************************************************************************
                                    ;* Homerseklet szamitas
                                    ;*
                                    ;*
                                    ;*   Y  =    m      *  x  +   b
                                    ;* 10T  = 0.1 * x - 400   /*65536
                                    
                                    
                                    TRC:		.db 0x9A,0x19,0x00,0x00	;m = 0x00001999 vagy 199A
                                    		.db 0x00,0x00,0x70,0xFF	;b = 0xFF700000
                                    
                                    Calc_Temp:
                                    		clr	mant1h
                                    		clr	mant1hh			;ACC1 = ADC value 0..16383
                                    
                                    		ldi	ZL,Low(TRC*2)		;konstansok
                                    		ldi	ZH,High(TRC*2)
                                    
                                    		rcall	LinearF
                                    YCalcEnd:	sts	Temperature+0,mant1h
                                    		sts	Temperature+1,mant1hh
                                    		ret
                                    
                                    
                                    
                                    ;**************************************************************************
                                    ;* Paratartalom szamitas
                                    ;*
                                    ;* Adatlap alpjan 12 bitre
                                    ;* x - paratartalom binaris erteke (ADC) 0..4095
                                    ;* T - homerseklet kiszamolt erteke C-ban
                                    ;*
                                    ; RHlin = -2.8*10^-6*x^2 + 4.05*10^-2 * x -4
                                    ; RHtrue= (T-25)*(10^-2 + 8*10^-5*x) +RHlin
                                    ;
                                    ;mindket egyenletet 10zel felszorozzuk a kijelzes miatt (T erteket nem az eleve 10T)
                                    ; 
                                    ;Resz szamitasok:
                                    ; a, (T-250)               - sub32
                                    ; b, ((10^-1 + 8*10^-4*x)) - linf
                                    ; c, 4.05*10^-1 * x - 40   - linf
                                    ; d, -2.8*10^-5*x^2	   - negyzet eftedi
                                    ;
                                    ; e, a*b
                                    ;
                                    ; RHtrue=a*b+c+d
                                    ;
                                    ;
                                    ;*
                                    ;*
                                    
                                    ;*   Y  =   m  *  x  +  b
                                    ;*  'B' = 0.0008 * x + 0.1
                                    
                                    PartB:		.db 0x34,0x00,0x00,0x00	;m = 0x00000034    0.0008 *65536
                                    		.db 0x9A,0x19,0x00,0x00	;b = 0x0000199A    0.1 * 65536
                                    
                                    ;*   Y  =   m  *  x  +  b
                                    ;*  'C' = 0.405 * x - 40
                                    
                                    PartC:		.db 0xAE,0x67,0x00,0x00	;m = 0x000067AE  0.405 *65536
                                    		.db 0x00,0x00,0xD8,0xFF	;b = 0xFFD80000  -40 * 65536
                                    
                                    
                                    CalcHum:
                                    		mov	R6,mant1
                                    		mov	R7,mant1m		;paratartalmat elmentjuk
                                    						;homerseklet mar kiszamolva memoriban van
                                    		clr	mant1h
                                    		clr	mant1hh			;ACC1 = ADC value 0..4095
                                    
                                    		ldi	ZL,Low(PartB*2)		;konstansok a 'B' szamitashoz
                                    		ldi	ZH,High(PartB*2)
                                    		rcall	LinearF			;ACC1-ben a 'B' szamitas eredmenye
                                    
                                    						;itt az 'A' szamitasa jon
                                    						; T-250
                                    		lds	mant2,Temperature+0
                                    		lds	mant2m,Temperature+1
                                    		clr	mant2h
                                    		clr	mant2hh			;ACC2 homerseklet
                                    		subi	mant2,250
                                    		sbci	mant2m,0
                                    		sbci	mant2h,0
                                    		sbci	mant2hh,0		;levontunk 250-t
                                    
                                    		rcall	UMUL			;acc1 = E = A * B  /*65536
                                    
                                    
                                    		push	mant1
                                    		push	mant1m
                                    		push	mant1h
                                    		push	mant1hh
                                    
                                    		mov	mant1,R6
                                    		mov	mant1m,R7		;x erteke
                                    		clr	mant1h
                                    		clr	mant1hh
                                    		ldi	ZL,Low(PartC*2)		;konstansok a 'C' szamitashoz
                                    		ldi	ZH,High(PartC*2)
                                    		rcall	LinearF			;ACC1-ben a 'C' szamitas eredmenye
                                    		pop	mant2hh
                                    		pop	mant2h
                                    		pop	mant2m
                                    		pop	mant2
                                    		rcall	add32
                                                    
                                    		push	mant1
                                    		push	mant1m
                                    		push	mant1h
                                    		push	mant1hh			
                                    
                                    
                                    		mov	mant1,R6
                                    		mov	mant1m,R7		;x erteke
                                    		clr	mant1h
                                    		clr	mant1hh
                                    
                                    		mov	mant2,R6
                                    		mov	mant2m,R7		;x erteke
                                    		clr	mant2h
                                    		clr	mant2hh
                                    		rcall	UMUL			;ACC1 = X^2
                                    
                                    		ldi	mant2,0xD6
                                    		ldi	mant2m,0x01
                                    		ldi	mant2h,0x00
                                    		ldi	mant2hh,0x00		;2.8*10^-5 * 65536*256
                                    		rcall	UMUL
                                    
                                    		clr	mant2hh
                                    		mov	mant2h,mant1hh
                                    		mov	mant2m,mant1h
                                    		mov	mant2,mant1m		;256-tal osztjuk az eredmenyt
                                    
                                    		pop	mant1hh
                                    		pop	mant1h
                                    		pop	mant1m
                                    		pop	mant1
                                    		rcall	sub32
                                    					;ACC1-ben a vegeredmeny
                                    
                                    		sts	Humidity+0,mant1h
                                    		sts	Humidity+1,mant1hh	;65536 valo szorzas miatt csak
                                    						; a felo 16 bit kell
                                    
                                    		ret
                                    
                                    
                                    
                                 

Programming the AVR Microcontrollers in Assember Machine Language

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Atmel AVR From Wikipedia, the free encyclopedia (Redirected from Avr) Jump to: navigation, search The AVRs are a family of RISC microcontrollers from Atmel. Their internal architecture was conceived by two students: Alf-Egil Bogen and Vegard Wollan, at the Norwegian Institute of Technology (NTH] and further developed at Atmel Norway, a subsidiary founded by the two architects. Atmel recently released the Atmel AVR32 line of microcontrollers. These are 32-bit RISC devices featuring SIMD and DSP instructions, along with many additional features for audio and video processing, intended to compete with ARM based processors. Note that the use of "AVR" in this article refers to the 8-bit RISC line of Atmel AVR Microcontrollers. The acronym AVR has been reported to stand for Advanced Virtual RISC. It's also rumoured to stand for the company's founders: Alf and Vegard, who are evasive when questioned about it. Contents [hide] 1 Device Overview 1.1 Program Memory 1.2 Data Memory and Registers 1.3 EEPROM 1.4 Program Execution 1.5 Speed 2 Development 3 Features 4 Footnotes 5 See also 6 External Links 6.1 Atmel Official Links 6.2 AVR Forums & Discussion Groups 6.3 Machine Language Development 6.4 C Language Development 6.5 BASIC & Other AVR Languages 6.6 AVR Butterfly Specific 6.7 Other AVR Links [edit] Device Overview The AVR is a Harvard architecture machine with programs and data stored and addressed separately. Flash, EEPROM, and SRAM are all integrated onto a single die, removing the need for external memory (though still available on some devices). [edit] Program Memory Program instructions are stored in semi-permanent Flash memory. Each instruction for the AVR line is either 16 or 32 bits in length. The Flash memory is addressed using 16 bit word sizes. The size of the program memory is indicated in the naming of the device itself. For instance, the ATmega64x line has 64Kbytes of Flash. Almost all AVR devices are self-programmable. [edit] Data Memory and Registers The data address space consists of the register file, I/O registers, and SRAM. The AVRs have thirty-two single-byte registers and are classified as 8-bit RISC devices. The working registers are mapped in as the first thirty-two memory spaces (000016-001F16) followed by the 64 I/O registers (002016-005F16). The actual usable RAM starts after both these sections (address 006016). (Note that the I/O register space may be larger on some more extensive devices, in which case memory mapped I/O registers will occupy a portion of the SRAM.) Even though there are separate addressing schemes and optimized opcodes for register file and I/O register access, all can still be addressed and manipulated as if they were in SRAM. [edit] EEPROM Almost all devices have on-die EEPROM. This is most often used for long-term parameter storage to be retrieved even after cycling the power of the device. [edit] Program Execution Atmel's AVRs have a single level pipeline design. The next machine instruction is fetched as the current one is executing. Most instructions take just one or two clock cycles, making AVRs relatively fast among the eight-bit microcontrollers. The AVR family of processors were designed for the efficient execution of compiled C code. The AVR instruction set is more orthogonal than most eight-bit microcontrollers, however, it is not completely regular: Pointer registers X, Y, and Z have addressing capabilities that are different from each other. Register locations R0 to R15 have different addressing capabilities than register locations R16 to R31. I/O ports 0 to 31 have different addressing capabilities than I/O ports 32 to 63. CLR affects flags, while SER does not, even though they are complementary instructions. CLR set all bits to zero and SER sets them to one. (Note though, that neither CLR nor SER are native instructions. Instead CLR is syntactic sugar for [produces the same machine code as] EOR R,R while SER is syntactic sugar for LDI R,$FF. Math operations such as EOR modify flags while moves/loads/stores/branches such as LDI do not.) [edit] Speed The AVR line can normally support clock speeds from 0-16MHz, with some devices reaching 20MHz. Lower powered operation usually requires a reduced clock speed. All AVRs feature an on-chip oscillator, removing the need for external clocks or resonator circuitry. Because many operations on the AVR are single cycle, the AVR can achieve up to 1MIPS per MHz. [edit] Development AVRs have a large following due to the free and inexpensive development tools available, including reasonably priced development boards and free development software. The AVRs are marketed under various names that share the same basic core but with different peripheral and memory combinations. Some models (notably, the ATmega range) have additional instructions to make arithmetic faster. Compatibility amongst chips is fairly good. See external links for sites relating to AVR development. [edit] Features Current AVRs offer a wide range of features: RISC Core Running Many Single Cycle Instructions Multifunction, Bi-directional I/O Ports with Internal, Configurable Pull-up Resistors Multiple Internal Oscillators Internal, Self-Programmable Instruction Flash Memory up to 256K In-System Programmable using ICSP, JTAG, or High Voltage methods Optional Boot Code Section with Independent Lock Bits for Protection Internal Data EEPROM up to 4KB Internal SRAM up to 8K 8-Bit and 16-Bit Timers PWM Channels & dead time generator Lighting (PWM Specific) Controller models Dedicated IC Compatible Two-Wire Interface (TWI) Synchronous/Asynchronous Serial Peripherals (UART/USART) (As used with RS-232,RS-485, and more) Serial Peripheral Interface (SPI) CAN Controller Support USB Controller Support Proper High-speed hardware & Hub controller with embedded AVR. Also freely available low-speed (HID) software emulation Ethernet Controller Support Universal Serial Interface (USI) for Two or Three-Wire Synchronous Data Transfer Analog Comparators LCD Controller Support 10-Bit A/D Converters, with multiplex of up to 16 channels Brownout Detection Watchdog Timer (WDT) Low-voltage Devices Operating Down to 1.8v Multiple Power-Saving Sleep Modes picoPower Devices Atmel AVR assembler programming language Atmel AVR machine programming language Atmel AVR From Wikipedia, the free encyclopedia (Redirected from Avr) Jump to: navigation, search The AVRs are a family of RISC microcontrollers from Atmel. Their internal architecture was conceived by two students: Alf-Egil Bogen and Vegard Wollan, at the Norwegian Institute of Technology (NTH] and further developed at Atmel Norway, a subsidiary founded by the two architects. Atmel recently released the Atmel AVR32 line of microcontrollers. These are 32-bit RISC devices featuring SIMD and DSP instructions, along with many additional features for audio and video processing, intended to compete with ARM based processors. Note that the use of "AVR" in this article refers to the 8-bit RISC line of Atmel AVR Microcontrollers. The acronym AVR has been reported to stand for Advanced Virtual RISC. It's also rumoured to stand for the company's founders: Alf and Vegard, who are evasive when questioned about it. Contents [hide] 1 Device Overview 1.1 Program Memory 1.2 Data Memory and Registers 1.3 EEPROM 1.4 Program Execution 1.5 Speed 2 Development 3 Features 4 Footnotes 5 See also 6 External Links 6.1 Atmel Official Links 6.2 AVR Forums & Discussion Groups 6.3 Machine Language Development 6.4 C Language Development 6.5 BASIC & Other AVR Languages 6.6 AVR Butterfly Specific 6.7 Other AVR Links [edit] Device Overview The AVR is a Harvard architecture machine with programs and data stored and addressed separately. Flash, EEPROM, and SRAM are all integrated onto a single die, removing the need for external memory (though still available on some devices). [edit] Program Memory Program instructions are stored in semi-permanent Flash memory. Each instruction for the AVR line is either 16 or 32 bits in length. The Flash memory is addressed using 16 bit word sizes. The size of the program memory is indicated in the naming of the device itself. For instance, the ATmega64x line has 64Kbytes of Flash. Almost all AVR devices are self-programmable. [edit] Data Memory and Registers The data address space consists of the register file, I/O registers, and SRAM. The AVRs have thirty-two single-byte registers and are classified as 8-bit RISC devices. The working registers are mapped in as the first thirty-two memory spaces (000016-001F16) followed by the 64 I/O registers (002016-005F16). The actual usable RAM starts after both these sections (address 006016). (Note that the I/O register space may be larger on some more extensive devices, in which case memory mapped I/O registers will occupy a portion of the SRAM.) Even though there are separate addressing schemes and optimized opcodes for register file and I/O register access, all can still be addressed and manipulated as if they were in SRAM. [edit] EEPROM Almost all devices have on-die EEPROM. This is most often used for long-term parameter storage to be retrieved even after cycling the power of the device. [edit] Program Execution Atmel's AVRs have a single level pipeline design. The next machine instruction is fetched as the current one is executing. Most instructions take just one or two clock cycles, making AVRs relatively fast among the eight-bit microcontrollers. The AVR family of processors were designed for the efficient execution of compiled C code. The AVR instruction set is more orthogonal than most eight-bit microcontrollers, however, it is not completely regular: Pointer registers X, Y, and Z have addressing capabilities that are different from each other. Register locations R0 to R15 have different addressing capabilities than register locations R16 to R31. I/O ports 0 to 31 have different addressing capabilities than I/O ports 32 to 63. CLR affects flags, while SER does not, even though they are complementary instructions. CLR set all bits to zero and SER sets them to one. (Note though, that neither CLR nor SER are native instructions. Instead CLR is syntactic sugar for [produces the same machine code as] EOR R,R while SER is syntactic sugar for LDI R,$FF. Math operations such as EOR modify flags while moves/loads/stores/branches such as LDI do not.) [edit] Speed The AVR line can normally support clock speeds from 0-16MHz, with some devices reaching 20MHz. Lower powered operation usually requires a reduced clock speed. All AVRs feature an on-chip oscillator, removing the need for external clocks or resonator circuitry. Because many operations on the AVR are single cycle, the AVR can achieve up to 1MIPS per MHz. [edit] Development AVRs have a large following due to the free and inexpensive development tools available, including reasonably priced development boards and free development software. The AVRs are marketed under various names that share the same basic core but with different peripheral and memory combinations. Some models (notably, the ATmega range) have additional instructions to make arithmetic faster. Compatibility amongst chips is fairly good. See external links for sites relating to AVR development. [edit] Features Current AVRs offer a wide range of features: RISC Core Running Many Single Cycle Instructions Multifunction, Bi-directional I/O Ports with Internal, Configurable Pull-up Resistors Multiple Internal Oscillators Internal, Self-Programmable Instruction Flash Memory up to 256K In-System Programmable using ICSP, JTAG, or High Voltage methods Optional Boot Code Section with Independent Lock Bits for Protection Internal Data EEPROM up to 4KB Internal SRAM up to 8K 8-Bit and 16-Bit Timers PWM Channels & dead time generator Lighting (PWM Specific) Controller models Dedicated IC Compatible Two-Wire Interface (TWI) Synchronous/Asynchronous Serial Peripherals (UART/USART) (As used with RS-232,RS-485, and more) Serial Peripheral Interface (SPI) CAN Controller Support USB Controller Support Proper High-speed hardware & Hub controller with embedded AVR. Also freely available low-speed (HID) software emulation Ethernet Controller Support Universal Serial Interface (USI) for Two or Three-Wire Synchronous Data Transfer Analog Comparators LCD Controller Support 10-Bit A/D Converters, with multiplex of up to 16 channels Brownout Detection Watchdog Timer (WDT) Low-voltage Devices Operating Down to 1.8v Multiple Power-Saving Sleep Modes picoPower Devices Atmel AVR assembler programming language Atmel AVR machine programming language Atmel AVR From Wikipedia, the free encyclopedia (Redirected from Avr) Jump to: navigation, search The AVRs are a family of RISC microcontrollers from Atmel. Their internal architecture was conceived by two students: Alf-Egil Bogen and Vegard Wollan, at the Norwegian Institute of Technology (NTH] and further developed at Atmel Norway, a subsidiary founded by the two architects. Atmel recently released the Atmel AVR32 line of microcontrollers. These are 32-bit RISC devices featuring SIMD and DSP instructions, along with many additional features for audio and video processing, intended to compete with ARM based processors. Note that the use of "AVR" in this article refers to the 8-bit RISC line of Atmel AVR Microcontrollers. The acronym AVR has been reported to stand for Advanced Virtual RISC. It's also rumoured to stand for the company's founders: Alf and Vegard, who are evasive when questioned about it. Contents [hide] 1 Device Overview 1.1 Program Memory 1.2 Data Memory and Registers 1.3 EEPROM 1.4 Program Execution 1.5 Speed 2 Development 3 Features 4 Footnotes 5 See also 6 External Links 6.1 Atmel Official Links 6.2 AVR Forums & Discussion Groups 6.3 Machine Language Development 6.4 C Language Development 6.5 BASIC & Other AVR Languages 6.6 AVR Butterfly Specific 6.7 Other AVR Links [edit] Device Overview The AVR is a Harvard architecture machine with programs and data stored and addressed separately. Flash, EEPROM, and SRAM are all integrated onto a single die, removing the need for external memory (though still available on some devices). [edit] Program Memory Program instructions are stored in semi-permanent Flash memory. Each instruction for the AVR line is either 16 or 32 bits in length. The Flash memory is addressed using 16 bit word sizes. The size of the program memory is indicated in the naming of the device itself. For instance, the ATmega64x line has 64Kbytes of Flash. Almost all AVR devices are self-programmable. [edit] Data Memory and Registers The data address space consists of the register file, I/O registers, and SRAM. The AVRs have thirty-two single-byte registers and are classified as 8-bit RISC devices. The working registers are mapped in as the first thirty-two memory spaces (000016-001F16) followed by the 64 I/O registers (002016-005F16). The actual usable RAM starts after both these sections (address 006016). (Note that the I/O register space may be larger on some more extensive devices, in which case memory mapped I/O registers will occupy a portion of the SRAM.) Even though there are separate addressing schemes and optimized opcodes for register file and I/O register access, all can still be addressed and manipulated as if they were in SRAM. [edit] EEPROM Almost all devices have on-die EEPROM. This is most often used for long-term parameter storage to be retrieved even after cycling the power of the device. [edit] Program Execution Atmel's AVRs have a single level pipeline design. The next machine instruction is fetched as the current one is executing. Most instructions take just one or two clock cycles, making AVRs relatively fast among the eight-bit microcontrollers. The AVR family of processors were designed for the efficient execution of compiled C code. The AVR instruction set is more orthogonal than most eight-bit microcontrollers, however, it is not completely regular: Pointer registers X, Y, and Z have addressing capabilities that are different from each other. Register locations R0 to R15 have different addressing capabilities than register locations R16 to R31. I/O ports 0 to 31 have different addressing capabilities than I/O ports 32 to 63. CLR affects flags, while SER does not, even though they are complementary instructions. CLR set all bits to zero and SER sets them to one. (Note though, that neither CLR nor SER are native instructions. Instead CLR is syntactic sugar for [produces the same machine code as] EOR R,R while SER is syntactic sugar for LDI R,$FF. Math operations such as EOR modify flags while moves/loads/stores/branches such as LDI do not.) [edit] Speed The AVR line can normally support clock speeds from 0-16MHz, with some devices reaching 20MHz. Lower powered operation usually requires a reduced clock speed. All AVRs feature an on-chip oscillator, removing the need for external clocks or resonator circuitry. Because many operations on the AVR are single cycle, the AVR can achieve up to 1MIPS per MHz. [edit] Development AVRs have a large following due to the free and inexpensive development tools available, including reasonably priced development boards and free development software. The AVRs are marketed under various names that share the same basic core but with different peripheral and memory combinations. Some models (notably, the ATmega range) have additional instructions to make arithmetic faster. Compatibility amongst chips is fairly good. See external links for sites relating to AVR development. [edit] Features Current AVRs offer a wide range of features: RISC Core Running Many Single Cycle Instructions Multifunction, Bi-directional I/O Ports with Internal, Configurable Pull-up Resistors Multiple Internal Oscillators Internal, Self-Programmable Instruction Flash Memory up to 256K In-System Programmable using ICSP, JTAG, or High Voltage methods Optional Boot Code Section with Independent Lock Bits for Protection Internal Data EEPROM up to 4KB Internal SRAM up to 8K 8-Bit and 16-Bit Timers PWM Channels & dead time generator Lighting (PWM Specific) Controller models Dedicated IC Compatible Two-Wire Interface (TWI) Synchronous/Asynchronous Serial Peripherals (UART/USART) (As used with RS-232,RS-485, and more) Serial Peripheral Interface (SPI) CAN Controller Support USB Controller Support Proper High-speed hardware & Hub controller with embedded AVR. Also freely available low-speed (HID) software emulation Ethernet Controller Support Universal Serial Interface (USI) for Two or Three-Wire Synchronous Data Transfer Analog Comparators LCD Controller Support 10-Bit A/D Converters, with multiplex of up to 16 channels Brownout Detection Watchdog Timer (WDT) Low-voltage Devices Operating Down to 1.8v Multiple Power-Saving Sleep Modes picoPower Devices Atmel AVR assembler programming language Atmel AVR machine programming language