Tick counter
Trigger signal
Counter reload
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Control Registers
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SPNU563A–March 2018
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Multi-Buffered Serial Peripheral Interface Module (MibSPI) with Parallel Pin
Option (MibSPIP)
28.3.32 Tick Count Register (TICKCNT)
One of the trigger sources for TGs is an internal periodic time trigger. This time trigger is called a tick
counter and is basically a down-counter with a preload/reload value. Every time the tick counter detects an
underflow it reloads the initial value and toggles the trigger signal provided to the TGs.
The trigger signal, shown in Figure 28-67 as a square wave, illustrates the different trigger event types for
the TGs (for example, rising edge, falling edge, and both edges).
Figure 28-67. Tick Counter Operation
This register is shown in Figure 28-68 and described in Table 28-41.
Figure 28-68. Tick Count Register (TICKCNT) [offset = 90h]
31 30 29 28 27 16
TICKENA RELOAD CLKCTRL Reserved
R/W-0 R/S-0 R/W-0 R-0
15 0
TICKVALUE
R/W-0
LEGEND: R = Read only; R/W = Read/Write; S = Set; -n = value after reset
Table 28-41. Tick Count Register (TICKCNT) Field Descriptions
Bit Field Value Description
31 TICKENA Tick counter enable.
0 The internal tick counter is disabled. The counter value remains unchanged.
Note: When the tick counter is disabled, the trigger signal is forced low.
1 The internal tick counter is enabled and is clocked by the clock source selected by CLKCTRL.
When TICKENA goes from 0 to 1, the tick counter is automatically loaded with the contents of
TICKVALUE.
30 RELOAD Pre-load the tick counter. RELOAD is a set-only bit; writing a 1 reloads the tick counter with the
value stored in TICKVALUE. Reading RELOAD always returns a 0.
Note: When the tick counter is reloaded by the RELOAD bit, the trigger signal is not
toggled.
29-28 CLKCTRL Tick counter clock source control. CLKCTRL defines the clock source that is used to clock the
internal tick counter.
0 SPICLK of data word format 0 is selected as the clock source of the tick counter.
1h SPICLK of data word format 1 is selected as the clock source of the tick counter.
2h SPICLK of data word format 2 is selected as the clock source of the tick counter.
3h SPICLK of data word format 3 is selected as the clock source of the tick counter.
27-16 Reserved 0 Reads return 0. Writes have no effect.
15-0 TICKVALUE 0-FFFFh Initial value for the tick counter. TICKVALUE stores the initial value for the tick counter. The tick
counter is loaded with the contents of TICKVALUE every time an underflow condition occurs and
every time the RELOAD flag is set by the host.
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