Freescale Semiconductor MPC8260 User Manual
Page 1099
ATM AAL2
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor
32-37
0xA4
EPAYLOAD
Word
Reserved payload. Initialize to 0x6A6A6A6A.
0xA8
Trm
Word
(ABR only) The upper bound on the time between F-RM cells for an
active source. TM 4.0 defines the Trm period as 100 msec. The Trm value
is defined by the system clock and the time stamp timer prescaler (See
RTSCR). For time stamp prescalar of 1µs, Trm should be set to 100
ms/1µs = 100,000.
0xAC
Nrm
Hword
(ABR only) Controls the maximum cells the source may send for each
F-RM cell. Set to 32 cells.
0xAE
Mrm
Hword
(ABR only) Controls the bandwidth between F-RM, B-RM and user data
cell. Set to 2 cells.
0xB0
TCR
Hword
(ABR only) Tag cell rate. The minimum cell rate allowed for all ABR
channels. An ABR channel whose ACR is less than TCR sends only
out-of-rate F-RM cells at TCR. Should be set to 10 cells/sec as defined
in the TM 4.0. Uses the ATMF TM 4.0 floating-point format. Note that the
APC minimum cell rate should be at least TCR.
0xB2
ABR_RX_TCTE
Hword
(ABR only) Points to total of 16 bytes reserved dual-port RAM area used
by the CP. Should be 16-byte aligned. User-defined.
0xB4
RxQD_Base_Ext
Word
Points to the base address of the external RxQD table. The actual
address of the first RxQD in the table is RxQD_Base_Ext + 512*4.
User-defined.
0xB8
RX_UDC_Base
Word
Valid only for AAL2 VCs. Points to the base of the RX UDC header table
that contains the UDC headers of the AAL2 VCs. The pointer to a VC
UDC header is: RX_UDC_Base + 16*CH# (where CH# is the ATM
channel number)
0xBC
TX_UDC_Base
Word
Valid only for AAL2 VCs. Points to the base of the TX UDC header table
that contains the UDC headers of the AAL2 VCs. The pointer to a VC
UDC header is: TX_UDC_Base + 16*CH# (where CH# is the ATM
channel number)
0xC0–
0xDF
—
—
Reserved. Should be cleared during initialization.
0xE0
TCELL_TMP_BASE_EXT
Word
Transmit Cell Temporary base address. Points to a total of
64*last_AAL2_Ch# octets reserved in external memory for partially filled
cells. Note: TCELL_TMP_BASE_EXT must be on the same bus as the
all the AAL2 data buffers required for CPS, SSSAR and CID switching.
0xE4–
0xFB
—
—
Reserved. Should be cleared during initialization.
0xFC
PAD_TMP_BASE
Hword
PAD template base address. Points to an internal memory area that
contains the zero cell template. Should be 64-byte aligned. User-defined.
0xFE
—
—
Reserved. Should be cleared during initialization.
Table 32-13. AAL2 Parameter RAM (continued)
Offset
Name
Width
Description