USB97C100 Standard Microsystems Corporation, USB97C100 Datasheet - Page 45

• Manufacturer Part Number: USB97C100
• Description: USB97C100 Multi-endpoint Usb Peripheral Controller(not Recommended For Designs)
• Manufacturer: Standard Microsystems Corporation

SERIAL INTERFACE ENGINE (SIE) REGISTER DESCRIPTION
Packet Header Definition
The following header contains information to determine endpoint, status, length of the received packet, and the
payload “received data”.
Packet Description:
1.
2.
SMSC DS – USB97C100
OFFSET
<n + 7
0x008
0x007
0x006
0x005
0x004
0x003
0x002
0x001
0x000
Offset 0 to 7 is the packet header.
a)
b)
Offset 8 to n+7 is the actual data received from the USB bus and stored in memory.
i)
ii)
iii)
Offset 0x000 to 0x005 is generated by the SIE.
Offset 0x006 to 0x007 is generated by the SIEDMA.
Payload Data Byte n-1 (n is the payload data size, which is Byte Count -8)
Payload Data Byte 0
Last Packet Toggle Value
Bad_CRC
MSB 7
0
0
0
Offset 0x000 bit bit 5 - Bad_TOG- This bit is set when the SIE receives an unexpected
toggle. This is not necessarily an error condition, This bit could indicate a condition when
the return handshake packet is lost .
Offset 0x000 bit Last_TOG is the last toggle bit received.
Offset 0x000 bit Bad_CRC, is set when the SIE detects a bad CRC.
- For 0 Length Packet, Byte Count = 0x008
- For 1 byte Packet, Byte Count = 0x009
- For any Packet, (Byte Count-1) points to last byte of payload data
EXTENDED FRAME COUNT[15..11]
0
0
1
1
Last_TOG
6
0
0
Table 75 - Packet Header Definition
Bad_TOG
Current Packet Toggle Value
5
0
0
FRAME COUNT[7..0]
BYTE COUNT[7..0]
Page 45
RESERVED
TMP_ADDRESS[6..0]
4
0
0
0
0
1
0
1
3
0
PACKET ID[3..0]
ENDPOINT[3..0]
BYTE COUNT[10..8]
FRAME COUNT[10..8]
“BAD TOG” bit
2
1
0
0
1
1
LSB 0
Rev. 01/03/2001