SL811ST CYPRESS [Cypress Semiconductor], SL811ST Datasheet - Page 11

• Manufacturer Part Number: SL811ST
• Description: SL811S/T USB Dual Speed Slave Controller
• Manufacturer: CYPRESS [Cypress Semiconductor]

5.3
Each endpoint set has a control register defined as follows:
5.3.1
Pointer to memory buffer location for USB reads and writes.
5.3.2
The Endpoint Base Length is the maximum packet size for Out transfers from the Host. Essentially, this designates the largest
packet size that can be received by the SL811S/T. For Transfers In to Host, Base Length designates the size of the data packet
to be sent.
5.3.3
The packet status contains information relative to the packet that has been received or transmitted. The register is defined as
follows:
5.3.4
Contains the number of bytes left over (from ’Length’ field) after a packet is received. If an overflow condition occurs, i.e., the
received packet from host was greater than the Length field, a bit is set in the Packet Status Register indicating the condition.
The user can then determine the number of bytes received greater than the Length field specified by reading this register.
Document #: 38-08009 Rev. **
Bit Position
Bit Position
0
1
2
3
4
5
6
7
Endpoint Control Registers
Endpoint Base Address
Endpoint Base Length
Packet Status
Transfer Count
0
1
2
3
4
5
6
7
Next Data Set
Send STALL
Sequence
Bit Name
Reserved
Direction
Enable
Arm
ISO
Sequence
Bit Name
Time-out
Overflow
STALL
Setup
Error
ACK
NAK
Allows enabled transfers when set =’1’. Clears to '0' when transfer is complete.
When set = '1' allows transfers to this endpoint. When set 0 USB transactions are ignored.
If Enable = '1' and Arm = '0', the endpoint will return NAKs to USB transmissions.
When set = '1' transmit to Host. When '0', receive from Host.
'0' if next data set is ‘a’, '1' if next data set is 'b'
When set to '1' allows Isochronous mode for this endpoint.
Sequence Bit. '0' if DATA0, '1' if DATA1.
When set to ‘1’ sends Stall in response to next request on this endpoint.
Transmission Acknowledge.
Error detected in transmission.
Time-out occurred.
Sequence Bit. '0' if DATA0, '1' if DATA1.
'1' indicates Setup Packet
Overflow condition - maximum length exceeded during receives.
Slave returns NAK
Slave set STALL bit
Function
Function
SL811S/T
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