AT43USB320A_04 ATMEL [ATMEL Corporation], AT43USB320A_04 Datasheet - Page 81

• Manufacturer Part Number: AT43USB320A_04
• Description: Full-speed USB Microcontroller with an Embedded Hub
• Manufacturer: ATMEL [ATMEL Corporation]

1443E–USB–4/04
Hub Endpoint 0 Byte Count Register – HBYTE_CNT0
Function Endpoint 0..2 Byte Count Register – FBYTE_CNT0..2
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. Hub endpoint 1 has no byte count
register.
• Bit 7..5 – Reserved
These bits are reserved in the AT43USB320A and will read as zero.
• Bit 4..0 – BYTCT4..0: Byte Count – Length of Endpoint Data Packet
Function EP0 $1FCD
Function EP1 $1FCC
Function EP2 $1FCB
Hub EP0 $1FCF
Read/Write
Initial Value
Bit
R
7
–
–
–
–
0
R
6
–
–
–
–
0
R
5
–
–
–
–
0
BYTCT4
BYTCT4
BYTCT4
BYTCT4
R/W
4
0
BYTCT3
BYTCT3
BYTCT3
BYTCT3
R/W
3
0
BYTCT2
BYTCT2
BYTCT2
BYTCT2
R/W
2
0
AT43USB320A
BYTCT1
BYTCT1
BYTCT1
BYTCT1
R/W
1
0
BYTCT0
BYTCT0
BYTCT0
BYTCT0
R/W
0
0
HBYTE_CNT0
FBYTE_CNT0
FBYTE_CNT1
FBYTE_CNT2
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