SN8F2270B Series
USB 2.0 Low-Speed 8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD
Page 90
Version 1.3
9.5.5 USB endpoint’s ACK handshaking flag REGISTER
The status of endpoint’s ACK transaction.
094H
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
EP_ACK
EP2_ACK
EP1_ACK
Read/Write
R/W
R/W
After
reset
0
0
Bit [1:0]
EPn_ACK [1:0]:
EP1~EP2 ACK transaction
.
n= 1, 2
.
The bit is set whenever the endpoint that completes
with an ACK received.
0 = the endpoint (interrupt pipe) doesn’t complete with an ACK.
1 = the endpoint (interrupt pipe) complete with an ACK.
9.5.6 USB endpoint’s NAK handshaking flag REGISTER
The status of endpoint’s NAK transaction.
095H
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
EP_NAK
EP2_NAK
EP1_NAK
Read/Write
R/W
R/W
After
reset
0
0
Bit [1:0]
EPn_NAK [1:0]:
EP1~EP3 NAK transaction
.
n = 1, 2
.
The bit is set whenever the endpoint that completes
with an NAK received.
0 = the EPnNAK_INT_EN = 0 or the endpoint (interrupt pipe) doesn’t complete with an NAK.
1 = the EPnNAK_INT_EN = 1 and the endpoint (interrupt pipe) complete with an NAK.
9.5.7 USB ENDPOINT 0 ENABLE REGISTER
An endpoint 0 (EP0) is used to initialize and control the USB device. EP0 is bi-directional (Control pipe), as the device,
can both receive and transmit data, which provides to access the device configuration information and allows generic
USB status and control accesses.
096H
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
UE0R - UE0M1
UE0M0 - UE0C3 UE0C UE0C1 UE0C0
Read/Write -
R/W R/W - R/W
R/W
R/W
R/W
After
reset
- 0 0 - 0 0 0 0
Bit [3:0]
UE0C [3:0]:
Indicate the number of data bytes in a transaction: For IN transactions, firmware loads the
count with the number of bytes to be transmitted to the host from the endpoint 0 FIFO.
Bit [6:5]
UE0M
[1:0]:
The endpoint 0 modes determine how the SIE responds to USB traffic that the host sends to
the endpoint 0. For example, if the endpoint 0’s mode bit is set to 00 that is NAK IN/OUT mode as shown in
