AT43USB326-AU Atmel, AT43USB326-AU Datasheet - Page 38
AT43USB326-AU
Manufacturer Part Number
AT43USB326-AU
Description
IC USB KEYBOARD CTRLR 48LQFP
Manufacturer
Atmel
Series
AVR®r
Datasheet
1.AT43USB326-AC.pdf
(102 pages)
Specifications of AT43USB326-AU
Applications
Keyboard Controller
Core Processor
AVR
Program Memory Type
Mask ROM (16 kB)
Controller Series
AT43USB
Ram Size
512 x 8
Interface
USB
Number Of I /o
32
Voltage - Supply
4.4 V ~ 5.25 V
Operating Temperature
-40°C ~ 85°C
Mounting Type
Surface Mount
Package / Case
48-LQFP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
38
AT43USB326
Timer/Counter0 Control Register – TCCR0
• Bits 7..3 – Res: Reserved Bits
These bits are reserved bits in the AT43USB355 and always read as zero.
• Bits 2, 1, 0 – CS02, CS01, CS00: Clock Select0, bit 2, 1 and 0
The Clock Select0 bits 2, 1 and 0 define the prescaling source of Timer/Counter0.
Table 10. Clock 0 Prescale Select
The Stop condition provides a Timer Enable/Disable function. The CK down divided modes
are scaled directly from the CK oscillator clock. If the external pin modes are used for
Timer/Counter0, transitions on PB0/(T0) will clock the counter even if the pin is configured as
an output. This feature can give the user SW control of the counting.
Timer/Counter0 – TCNT0
The Timer/Counter0 is realized as an up-counter with read and write access. If the
Timer/Counter0 is written and a clock source is present, the Timer/Counter0 continues count-
ing in the clock cycle following the write operation.
Initial Value
Read/Write
$33 ($53)
Initial Value
Read/Write
$32 ($52)
Bit
Bit
CS02
0
0
0
0
1
1
1
1
R
7
–
0
MSB
R/W
7
0
R
6
–
0
CS01
R/W
6
–
0
0
0
1
1
0
0
1
1
R
5
–
0
R/W
5
–
0
CS00
R
4
–
0
0
1
0
1
0
1
0
1
R/W
4
–
0
R
3
–
0
R/W
Description
Stop, the Timer/Counter0 is stopped
CK
CK/8
CK/64
CK/256
CK/1024
External Pin T0, falling edge
External Pin T0, rising edge
3
–
0
CS02
R/W
2
0
R/W
2
–
0
CS01
R/W
R/W
1
0
1
–
0
CS00
R/W
LSB
R/W
3313D–USB–04/06
0
0
0
0
TCCR0
TCNT0