DR
AFT
DR
AFT
DRAFT
DR
D
RAFT
DRAFT
DRA
FT DRAF
D
RAFT DRAFT DRAFT DRAFT DRAFT D
DRAFT
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FT DRAFT DRAFT DRAFT DRA
UM10316_0
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 00.06 — 17 December 2008
252 of 571
NXP Semiconductors
UM10316
Chapter 17: LPC29xx timer 0/1/2/3
5.5 Timer external-match register
The EMR provides both control and status of the external match pins. The external match
flags and the match outputs can either toggle, go to logic 0, go to logic 1 or maintain state
when the contents of the match register are equal to the contents of the timer counter.
Note that the match output is set to a specific level on writing the CTRL bits.
4
RESET_2
R/W
1
Reset on match MR2 and TC. When logic 1 the
timer counter is reset if MR2 matches TC
0*
3
STOP_1
R/W
1
Stop on match MR1 and TC. When logic 1 the
timer and prescale counter stop counting if
MR1 matches TC
0*
2
RESET_1
R/W
1
Reset on match MR1 and TC. When logic 1 the
timer counter is reset if MR1 matches TC
0*
1
STOP_0
R/W
1
Stop on match MR0 and TC. When logic 1 the
timer and prescale counter stop counting if
MR0 matches TC
0*
0
RESET_0
R/W
1
Reset on match MR0 and TC. When logic 1 the
timer counter is reset if MR0 matches TC
0*
Table 208. MCR register bits
…continued
* = reset value
Bit
Variable name
Access
Value
Description
Table 209. EMR register bits
* = reset value
Bit
Variable name
Access
Value
Description
31 to 10
reserved
R
-
Reserved; do not modify. Read as logic 0
11 and 10
CTRL_3[1:0]
R/W
External match control 3
00*
Do nothing
01
Set logic 0
10
Set logic 1
11
Toggle
9 and 8
CTRL_2[1:0]
R/W
External match control 2
00*
Do nothing
01
Set logic 0
10
Set logic 1
11
Toggle
7 and 6
CTRL_1[1:0]
R/W
External match control 1
00*
Do nothing
01
Set logic 0
10
Set logic 1
11
Toggle