Enhanced Direct Memory Access (eDMA)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
Freescale Semiconductor
12-21
Preliminary
37–39 /
0x4 [5:7]
SSIZE
[0:2]
Source data transfer size.
000 8-bit
001 16-bit
010 32-bit
011 Reserved
100 16-byte (32-bit, 4-beat, WRAP4 burst)
101 32-byte (32-bit, 8 beat, WRAP8 burst)
110 Reserved
111 Reserved
The attempted specification of a reserved encoding causes a configuration error.
40–44 /
0x4 [8:12]
DMOD
[0:4]
Destination address modulo. See the SMOD[0:5] definition.
45–47 /
0x4 [13:15]
DSIZE
[0:2]
Destination data transfer size. See the SSIZE[0:2] definition.
48–63 /
0x4 [16:31]
SOFF
[0:15]
Source address signed offset. Sign-extended offset applied to the current source address
to form the next-state value as each source read is completed.
64–95 /
0x8 [0:31]
NBYTES
[0:31]
Inner “minor” byte transfer count. Number of bytes to be transferred in each service
request of the channel. As a channel is activated, the contents of the appropriate TCD is
loaded into the DMA engine, and the appropriate reads and writes performed until the
complete byte transfer count has been transferred. This is an indivisible operation and
cannot be stalled or halted. After the minor count is exhausted, the current values of the
SADDR and DADDR are written back into the local memory, the major iteration count is
decremented and restored to the local memory. If the major iteration count is completed,
additional processing is performed.
Note: The NBYTES value of 0x0000_0000 is interpreted as 0x1_0000_0000, thus
specifying a 4 GB transfer.
96–127 /
0xC [0:31]
SLAST
[0:31]
Last source address adjustment. Adjustment value added to the source address at the
completion of the outer major iteration count. This value can be applied to “restore” the
source address to the initial value, or adjust the address to reference the next data
structure.
128–159 /
0x10 [0:31]
DADDR
[0:31]
Destination address. Memory address pointing to the destination data.
160 /
0x14 [0]
CITER.E_LINK
Enable channel-to-channel linking on minor loop completion. As the channel completes
the inner minor loop, this flag enables the linking to another channel, defined by
CITER.LINKCH[0:5]. The link target channel initiates a channel service request via an
internal mechanism that sets the TCD.START bit of the specified channel. If channel
linking is disabled, the CITER value is extended to 15 bits in place of a link channel
number. If the major loop is exhausted, this link mechanism is suppressed in favor of the
MAJOR.E_LINK channel linking.
0 The channel-to-channel linking is disabled.
1 The channel-to-channel linking is enabled.
Note: This bit must be equal to the BITER.E_LINK bit otherwise a configuration error will
be reported.
Table 12-19. TCDn Field Descriptions (continued)
Bits /
Word Offset
[n:n]
Name
Description