AT43USB325E-AU Atmel, AT43USB325E-AU Datasheet - Page 58

• Manufacturer Part Number: AT43USB325E-AU
• Description: IC USB KEYBOARD CTRLR 64LQFP
• Manufacturer: Atmel
• Series: AVR®r

Specifications of AT43USB325E-AU

• Applications: Keyboard Controller
• Core Processor: AVR
• Program Memory Type: SRAM (16 kB)
• Controller Series: AT43USB
• Ram Size: 512 x 8
• Interface: SPI, 3-Wire Serial
• Number Of I /o: 42
• Voltage - Supply: 4.4 V ~ 5.25 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 64-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7.3
7.3.1
7.3.2
7.3.3
58
Port C
AT43USB325
Port C Data Register – PORTC
Port C Data Direction Register – DDRC
Port C Input Pins Address – PINC
Port C is an 8-bit bi-directional I/O port with an internal pull-up resistor at each pin. Port C is
designed for use as the row inputs of a keyboard controller. Its output buffers can sink 4 mA.
Three I/O memory address locations are allocated for the Port C, one each for the Data Register
- PORTC, $15($35), Data Direction Register - DDRC, $14($34) and the Port C Input Pins –
PINC, $13($33). The Port C Input Pin’s address is read only, while the Data Register and the
Data Direction Register are read/write.
The Port C Input Pins address (PINC) is not a register, and this address enables access to the
physical value on each Port C pin. When reading PORTC, the Port C Data Latch is read, and
when reading PINC, the logical values present on the pins are read.
Initial Value
Initial Value
Read/Write
Read/Write
Read/Write
Initial Value
$15 ($35)
$14 ($34)
$13 ($33)
Bit
Bit
Bit
PORTC7
PINC7
DDC7
R/W
R/W
N/A
7
0
7
0
R
7
PORTC6
PINC6
DDC6
R/W
R/W
N/A
6
0
R
6
0
6
PORTC5
DDC5
PINC5
R/W
R/W
N/A
5
0
R
5
0
5
PORTC4
DDC4
PINC4
R/W
R/W
N/A
4
0
4
0
R
4
PORTC3
DDC3
PINC3
R/W
R/W
N/A
3
0
R
3
0
3
PORTC2
DDC2
PINC2
R/W
R/W
N/A
2
0
2
0
R
2
PORTC1
DDC1
PINC1
R/W
R/W
N/A
1
0
1
0
R
1
PORTC0
DDC0
PINC0
R/W
R/W
N/A
0
0
0
0
R
0
3355C–USB–4/05
PORTC
DDRC
PINC