mcs7717 MosChip, mcs7717 Datasheet - Page 12

• Manufacturer Part Number: mcs7717
• Description: Three Port Usb Hub With 1 Serial, 1 Printer
• Manufacturer: MosChip

Page 12
MCS7717
Three Port USB Hub with 1 Serial, 1 Printer
Endpoint
Descriptor #5
Status Endpoint
Status Endpoint:
The Status Endpoint returns 4 Bytes every 1 millisecond. These four Bytes are status information of the
Parallel Printer port and the Serial port.
Description for Byte-4 of Status Endpoint.
•
•
•
•
Reserved Reserved
ParOutFifo Empty 1 Indicates the Bulk-Out FIFO is empty.
SerOutFifo Status
ParInFifo Empty
SerInFifo Status
Byte-1: Interrupt Identification Register of the Serial port (IIR)
Byte-2: Reserved (Unused)
Byte-3: Device Status Register of the Parallel Printer port (DSR)
Byte-4: FIFO status of both the Parallel Printer port and the Serial port.
ParOutFifo Full
Bit[7]
ParInFifo Full
Bit
Bit[6]
(Bytes)
Offset
1 Indicates the Bulk-In FIFO is full.
1 Indicates the Bulk-In FIFO is empty.
1 Indicates the Bulk-Out FIFO is full.
1 Indicates the Bulk-Out FIFO is empty.
0 indicates the Bulk-Out FIFO is filled with Tx Data.
1 indicates the Bulk-In FIFO is filled with Rx Data.
0 indicates the Bulk-In FIFO is empty.
0
1
2
3
4
6
SerInFifo
Status
Bit[5]
bEndpointAddress
wMaxPacketSize
bDescriptorType
Field Name
bmAddress
SerOutFifo
bInterval
bLength
Status
Bit[4]
ParOutFifo
Empty
Bit[3]
(Bytes)
Description
Size
1
1
1
1
2
1
ParOutFifo
Value
04,00
(hex)
07
05
87
03
01
Bit[2]
Full
Descriptor Length = 7 Bytes
Endpoint-7, direction: IN
(Parallel Printer Port)
(Parallel Printer Port)
(Parallel Printer Port)
(Parallel Printer Port)
ParInFifo
Packet Size = 4 Bytes
Polling Interval (1mS)
Empty
Bit[1]
Type = ENDPOINT
Interrupt Endpoint
(Serial Port)
(Serial Port)
Comments
ParInFifo
Bit[0]
Full
Rev. 1.7