Freescale Semiconductor MPC8260 - Manual (Page 968)

ATM Controller and AAL0, AAL1, and AAL5
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
30-48 Freescale Semiconductor
Table 30-19. AAL1 Protocol-Specific RCT Field Descriptions
Offset Bits Name Description
0x0E 0–7 — Reserved, should be cleared.
8 PFM Partially filled mode.
0 Partially filled cells mode is not used.
1 Partially filled cells mode is used. The receiver copies only valid octets from the
AAL1 cell to the Rx buffer. The number of the valid octets from the beginning of the
AAL1 user data field is specified in the VOS (valid octet size) field.
9 SRT Synchronous residual time stamp. Unstructured format only. The PowerQUICC II
supports clock recovery using an external SRTS PLL. The PowerQUICC II tracks the
SRTS from the incoming four cells with SN = 1, 3, 5, and 7 and writes it to the external
SRTS device. Every eight cells the CP writes a valid SRTS to external logic. (See
Section 30.15, “SRTS Generation and Clock Recovery Using External Logic .”)
0 SRTS mode is not used.
1 SRTS mode is used.
10 INVE Inverted empty.
0 RxBD[E] is interpreted normally (1 = empty, 0 = not empty).
1 RxBD[E] is handled in negative logic (0 = empty, 1 = not empty).
11 STF Structured format
0 Unstructured format is used.
1 Structured format is used.
12–15 — Reserved, should be cleared.
0x10 0–3 SRTS_TMP Used by the CP to store the received SRTS code. After a cell with SN = 7 is received,
the CP writes the SRTS code to the external SRTS device.
4–11 — Reserved, should be cleared.
12–15 SRTS_DEV Selects an SRTS device, whose address is SRTS_BASE[0–27] + SRTS_DEV[28–31].
The 16 byte-aligned SRTS_BASE is taken from the parameter RAM.
0x12 0–1 — Reserved, should be cleared.
2–7 VOS Valid octet size. Specifies the number of valid octets from the beginning of the AAL1
user data field. For unstructured, service values 1–47 are valid; for structured service,
values 1-46 are valid. Partially filled cell mode only.
8 SPV Structured pointer valid. Should be user-initialized user to zero. Structured format only.
9–15 SP Structured pointer. Used by the CP to calculate the structured pointer. This field should
be initialized by the user to zero. Used in structured format only.
0x14 — RBDCNT RxBD count. Indicates how may bytes remain in the current Rx buffer. Initialized with
MRBLR whenever the CP opens a new buffer.
0x16 0–12 — Reserved, should be cleared.
13–15 SN Sequence number. Used by the CP to check incoming cell’s sequence number.