cx28560 Mindspeed Technologies, cx28560 Datasheet - Page 133

• Manufacturer Part Number: cx28560
• Description: Hdlc Controller
• Manufacturer: Mindspeed Technologies

CX28560 Data Sheet
5.8.5
Table 5-44. TBUFFC Flexiframe Control Register
28560-DSH-001-B
31:26
23:15
14:2
Bit
1:0
25
24
RSVD
TNFFRAMEIEN
TNFFrame
RSVD
TFFrameSize[14:2]
TFFrameSize[1:0]
Field Name
TBUFFC Flexiframe Control Register
This register contains the characteristics of the Flexiframe being programmed. When
moving to a new Flexiframe this register is vital for the smooth transition. In order to
swap to a new Flexiframe, the host should write the new Flexiframe to the
then write the Flexiframe Control register with the new frame size, the TNFFRAMEI
interrupt enable set to 1 or 0, and the TNFFRAME field set to 1. The host knows that
the transition to the new Flexiframe has been made either when a TNFFRAMEI
interrupt is generated (if the TNFFRAMEIEN was set to 1) or by polling the
TNFFRAME bit for a 0 value. An additional change of Flexiframe before some
acknowledgement has been recorded may produce undefined behavior.
Value
—
—
0
0
1
0
3
Mindspeed Technologies™
Reserved.
New Flexiframe Interrupt Disabled.
New Flexiframe Interrupt Enabled.
Once the TBUFFC has completed the switch to the new Flexiframe a New Flexiframe
interrupt will be generated.
New Flexiframe Indication.
This bit serves as an indication to the TBUFFC to switch to the new Flexiframe. When
the TBUFFC completes the switch to the new Flexiframe, it resets this indication to 0.
It is illegal for the system to set this bit to 0 as this will produce undefined behavior.
Reserved.
Flexiframe Size.
This field provides the RBUFFC the actual number of entries in the Flexiframe minus
one. Since the number of entries in the Flexiframe must be a multiple of four, the last
two bits of this field will be set to 11b. The value of this field may range from 11 to
21503 (indicating Flexiframe sizes of 12 to 21504 respectively).
Advance Information
Description
The CX28560 Memory Organization
Table
5-43,
5
-
43