
NUC126
Aug. 08, 2018
Page
380
of 943
Rev 1.03
NUC12
6 S
E
RI
E
S
T
E
CH
NI
CA
L R
E
F
E
RE
NCE
MA
NUA
L
DSCT4
DSCT3
DSCT1
DSCT0
DSCT2
DSCT_CTL
LSB 16 bits
0x0100
MSB 16 bits
0x2000
SRAM
Current DSCT4 Entry
First DSCT4 Entry
DSCT_FIRST
DSCT_DA
DSCT_SA
DSCT_NEXT
DSCT_DA
DSCT_SA
DSCT_CTL
PDMA_SCATBA
DSCT_NEXT
DSCT_DA
DSCT_SA
DSCT_CTL
Next DSCT4 Entry
0x2000_0100
0x2000_0104
0x2000_0108
0x2000_010C
0x2000_0200
0x2000_0204
0x2000_0208
0x2000_020C
LSB 16 bits
0x0200
Figure 6.12-4 Descriptor Table Link List Structure
The above link list table operation is DSCT state in Scatter-Gather Mode as shown in Figure 6.12-5.
When loading the information is finished, it will go to transfer state and start transfer by this information
automatically. However, if the next PDMA information is also in the Scatter-Gather mode, the hardware
will catch the next PDMA information block when the current task is finished. The Scatter-Gather mode
stops until the PDMA controller operation mode switch to basic mode and transfer once or directly
switch to idle state.
Idle State
Transfer State
DSCT State
OPMODE (PDMA_DSCTn_CTL[1:0])=0x1
OPMODE (PDMA_DSCTn_CTL[1:0])=0x0
OPMODE (PDMA_DSCTn_CTL[1:0])=0x2
Transfer done
AHB ready
Next Entry
OPMODE
(PDMA_DSCTn_CTL[1:0])=
0x0
Figure 6.12-5 Scatter-Gather Mode Finite State Machine