R8A66597BG RENESAS [Renesas Technology Corp], R8A66597BG Datasheet - Page 68

• Manufacturer Part Number: R8A66597BG
• Description: ASSP (USB2.0 2 Port Host/1 Port Peripheral Controller)
• Manufacturer: RENESAS [Renesas Technology Corp]

R8A66597FP/DFP/BG
2.12 Frame Number Register
♦ Frame number register [FRMNUM]
Remarks
* The OVRN bit is used for debugging. Set the timing so that an Overrun/Underrun error does not occur in the system.
2.12.1 Overrun/Underrun detection status bit (OVRN)
2.12.1.1 Host Controller function selection
2.12.1.2 Peripheral Controller function selection
2.12.2 CRC error detection status bit (CRCE)
R e v 1 . 0 1
13-11 Unassigned. Fix to "0".
10-0
OVRN
Bit
15
14
15
0
-
details.
OVRN
Overrun/Underrun detect status
CRCE
CRC error detect status
FRNM
Frame number
In an isochronous transfer type pipe, the controller sets "1" to this bit when an Overrun/Underrun is detected. When an
Overrun/Underrun is detected, the controller issues an internal NRDY request. Refer to 2.11.22 for details.
The software can clear this bit to "0" by writing "0" to this bit. In this case, write "1" to other bits of this register".
In an isochronous transfer pipe, the controller sets "1" to the bit when a CRC error or bit stuffing error has been
detected.
The software can clear this bit to "0" by writing "0" to this bit. In this case, write "1’ to other bits of this register".
When a CRC error or bit stuffing error is detected, the controller issues an internal NRDY request. Refer to 2.11.22 for
The controller sets "1" to this bit in either of the following cases:
(1) When data has not been written completely to the FIFO buffer despite transmission, and the Out-token issued
timing has been attained in the isochronous transfer type transmission pipe.
(2) When at least one part of the FIFO buffer is not free, and the In-token issued timing has been attained in the
isochronous transfer transmission pipe.
The controller sets "1" to this bit in either of the following cases:
(1) When data has not been written completely to the FIFO buffer despite transmission, and the Out-token is received
in the isochronous transfer type transmission pipe.
(2) When at least one part of the FIFO buffer is not free, and the Out-token is received in the isochronous transfer
receiving pipe.
CRCE
14
O c t 1 7 , 2 0 0 8
0
-
Name
13
?
?
12
?
?
p a g e 6 8 o f 1 8 3
11
?
?
Whether Overrun/Underrun error is detected or not is
set for the pipe transferred isochronously.
0: No error
1: Error
Whether CRC error is detected or not is set for the
pipe transferred isochronously.
0: No error
1: Error
Latest frame number is displayed.
10
0
-
9
0
-
8
0
-
Function
7
0
-
6
0
-
FRNM
5
0
-
4
0
-
Software Hardware Remarks
R/W(0)
R/W(0)
3
0
-
R
2
0
-
<Address: 4CH>
W
W
W
1
0
-
0
0
-