Universal Serial Bus (USB)
MPC885 PowerQUICC Family Reference Manual, Rev. 2
31-14
Freescale Semiconductor
31.10.1 Frame Number (FRAME_N)
This entry is used for frame number updates both in function mode and in host mode. In function mode it
is updated by the USB controller, in host mode it is updated by the application software.
31.10.1.1 Frame Number in Function Mode
This entry is updated by the USB controller in function mode whenever a SOF (start of frame) token is
received. The entry contains 11 bits that represent the frame number. An SOF interrupt is issued upon an
update of this entry.
Table 31-5
describes FRAME_N fields.
31.10.1.2 Frame Number In Host Mode
The entry is updated by the application software whenever a SOF (start of frame) token should be received.
The software should prepare the frame number and the crc and place it in FRAME_N field.
0x1C
TXUSBU_PTR
16 bits Tx microcode return address temp
0x1E
—
16 bits Reserved
1
Offset from endpoint parameter block base.
2
Note that the items in
boldface
should be initialized by the user.
3
These parameters need not be accessed in normal operation but may be helpful for debugging.
0
1
4
5
15
Field
V
1
1
This bit is set if the SOF token was received error free.
—
FRAME NUMBER
Reset
0000_0000_0000_0000
R/W
R/W
Addr
USB base + 0x10
Figure 31-9. Frame Number (FRAME_N) in Function mode
Table 31-5. FRAME_N Field Descriptions
Bits
Name
Description
0
V
The valid bit is set if the SOF token is received without error.
1–4
—
Reserved, should be cleared.
5–15
FRAME NUMBER
The frame number is loaded with the value received in the SOF packet. Be sure the
frame number is cleared before beginning USB operation.
Table 31-4. Endpoint Parameter Block (continued)
Offset
1
Name
2
Width
Description
Summary of Contents for PowerQUICC MPC870
Page 98: ...MPC885 PowerQUICC Family Reference Manual Rev 2 I 4 Freescale Semiconductor ...
Page 118: ...MPC885 Overview MPC885 PowerQUICC Family Reference Manual Rev 2 1 20 Freescale Semiconductor ...
Page 158: ...The MPC8xx Core MPC885 PowerQUICC Family Reference Manual Rev 2 3 18 Freescale Semiconductor ...
Page 288: ...MPC885 PowerQUICC Family Reference Manual Rev 2 III 4 Freescale Semiconductor ...
Page 554: ...MPC885 PowerQUICC Family Reference Manual Rev 2 V 6 Freescale Semiconductor ...
Page 1090: ...UTOPIA Interface MPC885 PowerQUICC Family Reference Manual Rev 2 43 8 Freescale Semiconductor ...
Page 1312: ...Byte Ordering MPC885 PowerQUICC Family Reference Manual Rev 2 A 8 Freescale Semiconductor ...
Page 1336: ...MPC885 PowerQUICC Family Reference Manual Rev 2 D 16 Freescale Semiconductor ...
Page 1358: ...MPC885 PowerQUICC Family Reference Manual Rev 2 D 38 Freescale Semiconductor ...
Page 1370: ...MPC880 MPC885 PowerQUICC Family Reference Manual Rev 2 E 4 Freescale Semiconductor ...
Page 1386: ...Revision History MPC885 PowerQUICC Family Reference Manual Rev 2 I 2 Freescale Semiconductor ...