cx29503 Mindspeed Technologies, cx29503 Datasheet - Page 206

• Manufacturer Part Number: cx29503
• Description: Cx29503 Broadband Access Multiplexer Data Sheet
• Manufacturer: Mindspeed Technologies

Register Description
0xA8—Receive Data Link FIFO 1 (RDL1)
Two different read byte values are supplied: WORD0 equals message status, and WORD1 equals message data.
The processor determines which byte value is located in the FIFO by first reading the receiver data link status
[RDL1_STAT; addr: 0A9]. In some cases, multiple consecutive status bytes may be placed in the FIFO, so the
processor must always read RDL1_STAT before reading RDL1 to distinguish between WORD0 and WORD1
byte values. However, each time a non-zero byte count [RDL1_CNT] status is read, the processor is guaranteed
the next RDL1_CNT reads from RDL1 will equal message data [WORD1] and not message status.
8-76
Table 8-35. Receive FIFO Threshold Selections
NOTE:
00 0000
00 0001
00 0010
11 1110
11 1111
FFC[5:0]
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Mindspeed Technologies™
A status byte occupies 1 byte of FIFO space, just the same as a message data byte
occupies 1 byte of FIFO space.
None
1 empty FIFO location
2 empty FIFO locations
62 empty FIFO locations
63 empty FIFO locations
Preliminary Information
Empty at RNEAR
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64 = RFULL
63 filled
62 filled
1 filled
0 filled = empty
Filled at RNEAR
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CX29503 Data Sheet
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29503-DSH-002-B