Electronic Components Datasheet Search
Selected language     English  ▼
Part Name
         Description


ATTINY2313 Datasheet(PDF) 89 Page - ATMEL Corporation

Part No. ATTINY2313
Description  8-bit AVR Microcontroller with 2K Bytes In-System Programmable Flash
Download  211 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  ATMEL [ATMEL Corporation]
Homepage  http://www.atmel.com
Logo 

 89 page
background image
89
ATtiny2313/V
2543C–AVR–12/03
Timer/Counter Clock
Sources
The Timer/Counter can be clocked by an internal or an external clock source. The clock
source is selected by the Clock Select logic which is controlled by the Clock Select
(CS12:0) bits located in the Timer/Counter control Register B (TCCR1B). For details on
clock sources and prescaler, see “Timer/Counter0 and Timer/Counter1 Prescalers” on
page 81.
Counter Unit
The main part of the 16-bit Timer/Counter is the programmable 16-bit bi-directional
counter unit. Figure 40 shows a block diagram of the counter and its surroundings.
Figure 40. Counter Unit Block Diagram
Signal description (internal signals):
Count
Increment or decrement TCNT1 by 1.
Direction
Select between increment and decrement.
Clear
Clear TCNT1 (set all bits to zero).
clk
T1
Timer/Counter clock.
TOP
Signalize that TCNT1 has reached maximum value.
BOTTOM
Signalize that TCNT1 has reached minimum value (zero).
The 16-bit counter is mapped into two 8-bit I/O memory locations: Counter High
(TCNT1H) containing the upper eight bits of the counter, and Counter Low (TCNT1L)
containing the lower eight bits. The TCNT1H Register can only be indirectly accessed
by the CPU. When the CPU does an access to the TCNT1H I/O location, the CPU
accesses the high byte temporary register (TEMP). The temporary register is updated
with the TCNT1H value when the TCNT1L is read, and TCNT1H is updated with the
temporary register value when TCNT1L is written. This allows the CPU to read or write
the entire 16-bit counter value within one clock cycle via the 8-bit data bus. It is impor-
tant to notice that there are special cases of writing to the TCNT1 Register when the
counter is counting that will give unpredictable results. The special cases are described
in the sections where they are of importance.
Depending on the mode of operation used, the counter is cleared, incremented, or dec-
remented at each timer clock (clk
T1). The clkT1 can be generated from an external or
internal clock source, selected by the Clock Select bits (CS12:0). When no clock source
is selected (CS12:0 = 0) the timer is stopped. However, the TCNT1 value can be
accessed by the CPU, independent of whether clk
T1 is present or not. A CPU write over-
rides (has priority over) all counter clear or count operations.
The counting sequence is determined by the setting of the Waveform Generation mode
bits (WGM13:0) located in the Timer/Counter Control Registers A and B (TCCR1A and
TCCR1B). There are close connections between how the counter behaves (counts) and
TEMP (8-bit)
DATA BUS (8-bit)
TCNTn (16-bit Counter)
TCNTnH (8-bit)
TCNTnL (8-bit)
Control Logic
Count
Clear
Direction
TOVn
(Int.Req.)
Clock Select
TOP
BOTTOM
Tn
Edge
Detector
( From Prescaler )
clk
Tn




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


Datasheet Download



Related Electronics Part Number

Part NumberComponents DescriptionHtml ViewManufacturer
AT90S44338-Bit AVR Microcontroller with 4K Bytes of In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation
ATTINY138-bit AVR Microcontroller with 1K Bytes In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation
ATMEGA165P8-bit AVR Microcontroller with 16K Bytes In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation
ATMEGA85158-bit AVR Microcontroller with 8K Bytes In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation
ATMEGA328-bit AVR Microcontroller with 32K Bytes In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation
ATMEGA168-bit AVR Microcontroller with 16K Bytes In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation
AT90S85158-Bit Microcontroller with 8K bytes In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation
ATTINY258-bit Microcontroller with 2/4/8K Bytes In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation
AT90S85158-Bit Microcontroller with 8K bytes In-System Programmable Flash 1 2 3 4 5 MoreATMEL Corporation

Link URL

Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Bookmark   |   Link Exchange   |   Manufacturer List
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  , 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