DMTimer 1ms
Table 20-33. Prescaler Clock Ratios Value (continued)
PRE
PTV
Divisor (PS)
1
5
64
1
6
128
1
7
256
The timer rate equation is as follows:
(0xFFFF FFFF – TLDR + 1) x timer Clock period x Clock Divider (PS)
With timer Clock period = 1/ timer Clock frequency and PS = 2(PTV + 1).
As example, if we consider a timer clock input of 32 KHz, with a PRE field equals to “0”, the timer output
period is:
Table 20-34. Value and Corresponding Interrupt Period
TLDR
Interrupt Period
0x0000 0000
37 h
0xFFFF 0000
2 s
0xFFFF FFF0
500 us
0xFFFF FFFE
62.5 us
20.2.3.9 Dual Mode Timer Under Emulation
During emulation mode (when PINSUSPENDN signal is active), the timer can/cannot continue running
according to the value of the EmuFree bit of the timer OCP configuration register (TIOCP_CFG).
If EmuFree is 1, timer execution is not stopped and, regardless of the value of PINSUSPENDN signal, and
the interrupt assertion is still generated when overflow is reached.
If EmuFree is 0, counters (prescaler/timer) are frozen and an increment start occurs again as soon as
PINSUSPENDN becomes inactive. The asynchronous input pin is internally synchronized on 2 TIMER
clock rising edges.
20.2.4 Use Cases
20.2.5 DMTIMER_1MS Registers
lists the memory-mapped registers for the DMTIMER_1MS. All register offset addresses not
listed in
should be considered as reserved locations and the register contents should not be
modified.
Table 20-35. DMTIMER_1MS REGISTERS
Offset
Acronym
Register Name
Section
0h
TIDR
This register contains the IP revision code
10h
TIOCP_CFG
This register controls the various parameters of the OCP
interface
14h
TISTAT
This register provides status information about the
module, excluding the interrupt status information
18h
TISR
The Timer Status Register is used to determine which of
the timer events requested an interrupt.
1Ch
TIER
This register controls (enable/disable) the interrupt
events
20h
TWER
This register controls (enable/disable) the wakeup
feature on specific interrupt events
24h
TCLR
This register controls optional features specific to the
timer functionality
3597
SPRUH73H – October 2011 – Revised April 2013
Timers
Copyright © 2011–2013, Texas Instruments Incorporated