ATMEGA168-15AZ Atmel, ATMEGA168-15AZ Datasheet - Page 261

• Manufacturer Part Number: ATMEGA168-15AZ
• Description: MCU AVR 16K FLASH 15MHZ 32-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA168-15AZ

• Package / Case: 32-TQFP, 32-VQFP
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 125°C
• Speed: 16MHz
• Number Of I /o: 23
• Eeprom Size: 512 x 8
• Core Processor: AVR
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Program Memory Size: 16KB (16K x 8)
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Connectivity: I²C, SPI, UART/USART
• Core Size: 8-Bit
• Cpu Family: ATmega
• Device Core: AVR
• Device Core Size: 8b
• Frequency (max): 16MHz
• Interface Type: 2-Wire/USART/Serial
• Total Internal Ram Size: 1KB
• # I/os (max): 23
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 32
• Package Type: TQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

23.1.6
7530I–AVR–02/10
Simple Assembly Code Example for a Boot Loader
Note that the RWWSB bit will always be read as zero in ATmega48. Nevertheless, it is recom-
mended to check this bit as shown in the code example, to ensure compatibility with devices
supporting Read-While-Write.
.equ
words
.org SMALLBOOTSTART
Write_page:
Wrloop:
;-the routine writes one page of data from RAM to Flash
; the first data location in RAM is pointed to by the Y pointer
; the first data location in Flash is pointed to by the Z-pointer
;-error handling is not included
;-the routine must be placed inside the Boot space
; (at least the Do_spm sub routine). Only code inside NRWW section can
; be read during Self-Programming (Page Erase and Page Write).
;-registers used: r0, r1, temp1 (r16), temp2 (r17), looplo (r24),
; loophi (r25), spmcrval (r20)
; storing and restoring of registers is not included in the routine
; register usage can be optimized at the expense of code size
;-It is assumed that either the interrupt table is moved to the Boot
; loader section or that the interrupts are disabled.
;
ldi
rcall
;
ldi
rcall
;
ldi
ldi
ld
ld
ldi
rcall
adiw
sbiw
brne
;
subi
sbci
ldi
rcall
;
ldi
Page Erase
re-enable the RWW section
transfer data from RAM to Flash page buffer
execute Page Write
re-enable the RWW section
PAGESIZEB = PAGESIZE*2
spmcrval, (1<<PGERS) | (1<<SELFPRGEN)
Do_spm
spmcrval, (1<<RWWSRE) | (1<<SELFPRGEN)
Do_spm
looplo, low(PAGESIZEB);init loop variable
loophi, high(PAGESIZEB);not required for PAGESIZEB<=256
r0, Y+
r1, Y+
spmcrval, (1<<SELFPRGEN)
Do_spm
ZH:ZL, 2
loophi:looplo, 2
Wrloop
ZL, low(PAGESIZEB)
ZH, high(PAGESIZEB) ;not required for PAGESIZEB<=256
spmcrval, (1<<PGWRT) | (1<<SELFPRGEN)
Do_spm
spmcrval, (1<<RWWSRE) | (1<<SELFPRGEN)
ATmega48/88/168 Automotive
;PAGESIZEB is page size in BYTES, not
;use subi for PAGESIZEB<=256
;restore pointer
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