Zakładka z wyszukiwarką danych komponentów
  Polish  ▼

Delete All
ON OFF
ALLDATASHEET.PL

X  

Preview PDF Download HTML

ATmega16-16PU Arkusz danych(PDF) 14 Page - ATMEL Corporation

Numer części ATmega16-16PU
Szczegółowy opis  8-bit Microcontroller with 16K Bytes In-Syustem Programmable Flash
Download  357 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Producent  ATMEL [ATMEL Corporation]
Strona internetowa  http://www.atmel.com
Logo ATMEL - ATMEL Corporation

ATmega16-16PU Arkusz danych(HTML) 14 Page - ATMEL Corporation

Back Button ATmega16-16PU Datasheet HTML 10Page - ATMEL Corporation ATmega16-16PU Datasheet HTML 11Page - ATMEL Corporation ATmega16-16PU Datasheet HTML 12Page - ATMEL Corporation ATmega16-16PU Datasheet HTML 13Page - ATMEL Corporation ATmega16-16PU Datasheet HTML 14Page - ATMEL Corporation ATmega16-16PU Datasheet HTML 15Page - ATMEL Corporation ATmega16-16PU Datasheet HTML 16Page - ATMEL Corporation ATmega16-16PU Datasheet HTML 17Page - ATMEL Corporation ATmega16-16PU Datasheet HTML 18Page - ATMEL Corporation Next Button
Zoom Inzoom in Zoom Outzoom out
 14 / 357 page
background image
14
2466S–AVR–05/09
ATmega16(L)
0. The Interrupt Vectors can be moved to the start of the Boot Flash section by setting the IVSEL
bit in the General Interrupt Control Register (GICR). Refer to “Interrupts” on page 45 for more
information. The Reset Vector can also be moved to the start of the boot Flash section by pro-
gramming the BOOTRST Fuse, see “Boot Loader Support – Read-While-Write Self-
Programming” on page 246.
When an interrupt occurs, the Global Interrupt Enable I-bit is cleared and all interrupts are dis-
abled. The user software can write logic one to the I-bit to enable nested interrupts. All enabled
interrupts can then interrupt the current interrupt routine. The I-bit is automatically set when a
Return from Interrupt instruction – RETI – is executed.
There are basically two types of interrupts. The first type is triggered by an event that sets the
Interrupt Flag. For these interrupts, the Program Counter is vectored to the actual Interrupt Vec-
tor in order to execute the interrupt handling routine, and hardware clears the corresponding
Interrupt Flag. Interrupt Flags can also be cleared by writing a logic one to the flag bit position(s)
to be cleared. If an interrupt condition occurs while the corresponding interrupt enable bit is
cleared, the Interrupt Flag will be set and remembered until the interrupt is enabled, or the flag is
cleared by software. Similarly, if one or more interrupt conditions occur while the Global Interrupt
Enable bit is cleared, the corresponding Interrupt Flag(s) will be set and remembered until the
global interrupt enable bit is set, and will then be executed by order of priority.
The second type of interrupts will trigger as long as the interrupt condition is present. These
interrupts do not necessarily have Interrupt Flags. If the interrupt condition disappears before the
interrupt is enabled, the interrupt will not be triggered.
When the AVR exits from an interrupt, it will always return to the main program and execute one
more instruction before any pending interrupt is served.
Note that the Status Register is not automatically stored when entering an interrupt routine, nor
restored when returning from an interrupt routine. This must be handled by software.
When using the CLI instruction to disable interrupts, the interrupts will be immediately disabled.
No interrupt will be executed after the CLI instruction, even if it occurs simultaneously with the
CLI instruction. The following example shows how this can be used to avoid interrupts during the
timed EEPROM write sequence.
Assembly Code Example
in
r16, SREG
; store SREG value
cli
; disable interrupts during timed sequence
sbi
EECR, EEMWE
; start EEPROM write
sbi
EECR, EEWE
out
SREG, r16
; restore SREG value (I-bit)
C Code Example
char
cSREG;
cSREG = SREG;
/* store SREG value */
/* disable interrupts during timed sequence */
_CLI();
EECR |= (1<<EEMWE); /* start EEPROM write */
EECR |= (1<<EEWE);
SREG = cSREG; /* restore SREG value (I-bit) */


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53  54  55  56  57  58  59  60  61  62  63  64  65  66  67  68  69  70  71  72  73  74  75  76  77  78  79  80  81  82  83  84  85  86  87  88  89  90  91  92  93  94  95  96  97  98  99  100   ...More


Arkusz danych Pobierz

Go To PDF Page


Link URL




Polityka prywatności
ALLDATASHEET.PL
Czy Alldatasheet okazała się pomocna?  [ DONATE ] 

O Alldatasheet   |   Reklama   |   Kontakt   |   Polityka prywatności   |   Linki   |   Lista producentów
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn