AT43USB325E-AC Atmel, AT43USB325E-AC Datasheet - Page 75

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

Specifications of AT43USB325E-AC

• 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: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 64-LQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

8.3.6
8.3.7
3355C–USB–4/05
Hub Endpoint 0 Byte Count Register – HBYTE_CNT0
Function Endpoint 0..3 Byte Count Register – FBYTE_CNT0..3
The contents of these registers stores the number of bytes to be sent or that was received by
USB Hub and Function endpoints. This count includes the 16-bit CRC. To get the actual byte
count of the data, subtract the count in the register by 2. The maximum byte count supported by
the AT43USB325 is 8 bytes. Hub endpoint 1 has no byte count register.
• Bit 7..6 – Reserved
These bits are reserved in the AT43USB325 and will read as zero.
• Bit 5..0 – BYTCT5..0: Byte Count – Length of Endpoint Data Packet
Function EP0 $1FCD
Function EP1 $1FCC
Function EP2 $1FCB
Function EP3 $1FCA
Hub EP0 $1FCF
Initial Value
Read/Write
Bit
R
7
–
–
–
–
–
0
R
6
–
–
–
–
–
0
BYTCT5
BYTCT5
BYTCT5
BYTCT5
BYTCT5
R
5
0
BYTCT4
BYTCT4
BYTCT4
BYTCT4
BYTCT4
R/W
4
0
BYTCT3
BYTCT3
BYTCT3
BYTCT3
BYTCT3
R/W
3
0
BYTCT2
BYTCT2
BYTCT2
BYTCT2
BYTCT2
R/W
2
0
BYTCT1
BYTCT1
BYTCT1
BYTCT1
BYTCT1
R/W
1
0
AT43USB325
BYTCT0
BYTCT0
BYTCT0
BYTCT0
BYTCT0
R/W
0
0
HBYTE_CNT0
FBYTE_CNT0
FBYTE_CNT1
FBYTE_CNT2
FBYTE_CNT3
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