28 USB FUNCTION CONTROLLER (USB)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
28-29
D7
DescriptorCmp
Shows a cause of interrupt directly.
Set to 1 when as many data as specified in the DescSize register have been replied in the Description
Reply function.
And the OUT_TranNAK bit of the EP0IntStat register is set to 1 as well as this bit, when changing to
the status stage takes place (the OUT token is received) before sending data up to the quantity specified
in the DescSize register.
D[6:2]
Reserved
D1
FIFO_IN_Cmp
Shows a cause of interrupt directly.
If the transfer direction of the endpoint bound to DMA (refer to the DMA_Join register) is the IN direc-
tion, this bit is set to 1 when the FIFO becomes empty after completion of the DMA transfer.
D0
FIFO_OUT_Cmp
Shows a cause of interrupt directly.
If the transfer direction of the endpoint bound to DMA (refer to the DMA_Join register) is the OUT di-
rection, this bit is set to 1 when the DMA transfer is completed.
EP0IntStat (EP0 Interrupt Status)
Register name Address
Bit
Name
Setting
Init. R/W
Remarks
EP0IntStat
(EP0 interrupt
status)
0x300c07
(8 bits)
D7–6 –
–
–
–
0 when being read.
D5
IN_TranACK
1 In transaction ACK
0 None
0
R(W)
D4
OUT_TranACK
1 Out transaction ACK
0 None
0
R(W)
D3
IN_TranNAK
1 In transaction NAK
0 None
0
R(W)
D2
OUT_TranNAK
1 Out transaction NAK
0 None
0
R(W)
D1
IN_TranErr
1 In transaction error
0 None
0
R(W)
D0
OUT_TranErr
1 Out transaction error
0 None
0
R(W)
This register displays the interrupt status of the endpoint EP0.
D[7:6]
Reserved
D5
IN_TranACK
Shows a cause of interrupt directly.
Set to 1 when ACK is received in the IN transaction.
D4
OUT_TranACK
Shows a cause of interrupt directly.
Set to 1 when ACK is replied in the OUT transaction.
D3
IN_TranNAK
Shows a cause of interrupt directly.
Set to 1 when NAK is replied in the IN transaction.
D2
OUT_TranNAK
Shows a cause of interrupt directly.
Set to 1 when NAK is replied in the OUT transaction.
D1
IN_TranErr
Shows a cause of interrupt directly.
Set to 1 when STALL is replied in the IN transaction, when an error occurred in the packet or when the
handshake is failed in Time-Out.
D0
OUT_TranErr
Shows a cause of interrupt directly.
Set to 1 when STALL is replied in the OUT transaction or when an error occurred in the packet.