LH79524/LH79525 User’s Guide
Universal Serial Bus Device
Version 1.0
17-25
17.2.3.5 Control Status Register 2 for IN EP 1, 2, and 3 (INCSR2)
The INCSR2 register allows software to configure USB access and the function of the
IN_PKT_RDY bit. Software should configure endpoints via INCSR2 before reading the
INCSR1 register.
Table 17-32. INCSR2 Register
BIT
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
FIELD
///
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RW
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
BIT
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
FIELD
///
AUTO_SET
ISO
///
USB_DMA_EN
F
RC_DAT
A
_TOG
///
RESET
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
TYPE
RO
RO
RO
RO
RO
RO
RO
RO
RW
RW
RW
RW
RW
RO
RO
RO
ADDR
0xFF 0x048
(with the INDEX register set to IN endpoint 1, 2, or 3)
Table 17-33. INCSR2 Fields
BITS
NAME
FUNCTION
31:8
///
Reserved
Reading returns 0. Write the reset value.
7
AUTO_SET
Auto Set IN_PKT_RDY Bit
Auto set the IN_PKT_RDY bit.
1 = IN_PKT_RDY is automatically set to 1, without intervention from software,
each time MAXP data is written. If software writes less than MAXP data, the
IN_PKT_RDY bit must be programmed to 1 by software. When two packets
are in the IN FIFO, IN_PKT_RDY will also be automatically set after the first
packet has been sent, if the second packet is the maximum packet size.
0 = Software must explicitly control the IN_PKT_RDY bit
6
ISO
Isochronous Mode Enable
Use this bit to enable Isochronous transfers.
1 = Enable the IN endpoint for isochronous transfers
0 = Enable the IN endpoint for bulk or interrupt transfers
5
///
Reserved
Reading returns 0. Write the reset value.
4
USB_DMA_EN
USB DMA Enable
This bit enables DMA Bulk transfers for the IN endpoint.
1 = FIFO is accessed via the DMA
0 = FIFO is accessed via direct Reads
3
FRC_DATA_TOG
Force Data Toggle
This bit can be used to force the endpoint IN data toggle to
switch and the data packet to be cleared from the FIFO, regardless of whether an
ACK was received. This can be used by interrupt IN endpoints that are used to
communicate rate feedback for isochronous endpoints.
1 = Force data toggle
0 = Normal operation
2:0
///
Reserved
Reading returns 0. Write the reset value.