26.8.14. Active Channel and Levels
Name:
ACTIVE
Offset:
0x30
Reset:
0x00000000
Property:
-
Bit
31
30
29
28
27
26
25
24
BTCNT[15:8]
Access
R
R
R
R
R
R
R
R
Reset
0
0
0
0
0
0
0
0
Bit
23
22
21
20
19
18
17
16
BTCNT[7:0]
Access
R
R
R
R
R
R
R
R
Reset
0
0
0
0
0
0
0
0
Bit
15
14
13
12
11
10
9
8
ABUSY
ID[4:0]
Access
R
R
R
R
R
R
Reset
0
0
0
0
0
0
Bit
7
6
5
4
3
2
1
0
LVLEX3
LVLEX2
LVLEX1
LVLEX0
Access
R
R
R
R
Reset
0
0
0
0
Bits 31:16 – BTCNT[15:0]: Active Channel Block Transfer Count
These bits hold the 16-bit block transfer count of the ongoing transfer. This value is stored in the active
channel and written back in the corresponding Write-Back channel memory location when the arbiter
grants a new channel access. The value is valid only when the active channel active busy flag (ABUSY)
is set.
Bit 15 – ABUSY: Active Channel Busy
This bit is cleared when the active transfer count is written back in the write-back memory section.
This bit is set when the next descriptor transfer count is read from the write-back memory section.
Bits 12:8 – ID[4:0]: Active Channel ID
These bits hold the channel index currently stored in the active channel registers. The value is updated
each time the arbiter grants a new channel transfer access request.
Bits 3,2,1,0 – LVLEXx: Level x Channel Trigger Request Executing [x=3..0]
This bit is set when a level-x channel trigger request is executing or pending.
This bit is cleared when no request is pending or being executed.
Atmel SAM L22G / L22J / L22N [DATASHEET]
Atmel-42402E-SAM L22G / L22J / L22N_Datasheet_Complete-07/2016
475