MAC7200 datasheet(307/976 Pages) FREESCALE

307 / 976 page

The SPP DMA Controller Module (SPP_DMA2)

MAC7200 Microcontroller Family Reference Manual, Rev. 2

Freescale Semiconductor

229

Figure 12-23 and Table 12-27 define word 6 of the TCDn structure, the dlast_sga field.

Figure 12-24 and Table 12-28 define word 7 of the TCDn structure, the biter and control/status fields.

24–16

citer[8:0]

Current “major” iteration count. This 9 or 15-bit count represents the current major loop count for the channel. It is

decremented each time the minor loop is completed and updated in the transfer control descriptor memory. Once

the major iteration count is exhausted, the channel performs a number of operations (e.g., final source and

destination address calculations), optionally generating an interrupt to signal channel completion before reloading

the citer field from the beginning iteration count (biter) field. When the citer field is initially loaded by software, it

must be set to the same value as that contained in the biter field. If the channel is configured to execute a single

service request, the initial values of biter and citer should be 0x0001.

15–0

doff[15:0]

Destination address signed offset. Sign-extended offset applied to the current destination address to form the

next-state value as each destination write is completed.

dlast_sga[31:16]

Reset

————————————————

9876543210

dlast_sga[15:00]

Reset

————————————————

= Unimplemented

Figure 12-23. TCDn Word 6 (TCDn.dlast_sga) Field

Table 12-27. TCDn Word 6 (TCDn.dlast_sga) Field Descriptions

Field

Description

31–0

dlast_sga

[31:0]

Last destination address adjustment or the memory address for the next transfer control descriptor to be loaded

into this channel (scatter/gather). If (TCD.e_sg = 0) then

Adjustment value added to the destination address at the completion of the outer major iteration count. This value

can be applied to “restore” the destination address to the initial value, or adjust the address to reference the next

data structure.

else

This address points to the beginning of a 0-modulo-32 region containing the next transfer control descriptor to be

loaded into this channel. This channel reload is performed as the major iteration count completes. The

scatter/gather address must be 0-modulo-32, else a configuration error is reported.

Table 12-26. TCDn Word 5 (TCDn.{doff,citer}) Field Descriptions (Continued)

Field

Description

MAC7200 Datasheet(PDF) 307 Page - Freescale Semiconductor, Inc

MAC7200 Datasheet(HTML) 307 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL