AT32F421
Series Reference Manual
2022.11.11
Page 276
Rev 2.02
11: Divided by 8
Bit 11: 8
ESF
0x0
rw
External signal filter
This field is used to filter an external signal. The external
signal can be sampled only after it has been generated N
times
0000: No filter, sampling by
f
𝐷𝑇𝑆
0001:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐶𝐾_𝐼𝑁𝑇
, N=2
0010:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐶𝐾_𝐼𝑁𝑇
, N=4
0011:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐶𝐾_𝐼𝑁𝑇
, N=8
0100:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/2, N=6
0101:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/2, N=8
0110:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/4, N=6
0111:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/4, N=8
1000:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/8, N=6
1001:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/8, N=8
1010:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/16, N=5
1011:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/16, N=6
1100:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/16, N=8
1101:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/32, N=5
1110:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/32, N=6
1111:
f
𝑆𝐴𝑀𝑃𝐿𝐼𝑁𝐺
=
f
𝐷𝑇𝑆
/32, N=8
Bit 7
STS
0x0
rw
Subordinate TMR synchronization
If enabled, master and slave timer can be synchronized.
0: Disabled
1: Enabled
Bit 6: 4
STIS
0x0
rw
Subordinate TMR input selection
This field is used to select the subordinate TMR input.
000: Internal selection 0 (IS0)
001: Internal selection 1 (IS1)
010: Internal selection 2 (IS2)
011: Internal selection 3 (IS3)
100: C1IRAW input detector (C1INC)
101: Filtered input 1 (C1IF1)
110: Filtered input 2 (C1IF2)
111: External input (EXT)
Refer to
for details on ISx for each timer.
Bit 3
COSSEL
0x0
rw
Channel output switch selection
This field is used to select the switch source of CxORAW
0: Select EXT as the switch source of CxORAW
1: Select CxORAW_OFF as the switch source of
CxORAW
Bit 2: 0
SMSEL
0x0
rw
Subordinate TMR mode selection
000: Slave mode is disabled
001: Encoder mode A
010: Encoder mode B
011: Encoder mode C
100: Reset mode - Rising edge of the TRGIN input
reinitializes the counter
101: Suspend mode - The counter starts counting when
the TRGIN is high
110: Trigger mode - A trigger event is generated at the
rising edge of the TRGIN input
111: External clock mode A - Rising edge of the TRGIN
input clocks the counter
Note: Refer to count mode section for details on
encoder mode A/B/C.
14.6.4.4 TMR1 DMA/interrupt enable register (TMR1_IDEN)
Bit
Register
Reset value
Type
Description
Bit 15
Reserved
0x0
resd
Kept at its default value.
Bit 14
TDEN
0x0
rw
Trigger DMA request enable
0: Disabled
1: Enabled