NXP Semiconductors MKW01Z128, Reference Manual

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35.4.11 Wake up MCU from low power modes
In low power modes, once enabled by TSI_GENCS[STPE] and TSI_GENCS[TSIIE],
TSI can bring MCU out of its low power modes(STOP, VLPS, VLLS,etc) by either end
of scan or out of range interrupt, that is, if TSI_GENCS[ESOR] is set, end of scan
interrupt is selected and otherwise, out of range is selected.
35.4.12 DMA function support
Transmit by DMA is supported only when TSI_DATA[DMAEN] is set. A DMA transfer
request is asserted when all the flags based on TSI_GENCS[ESOR] settings and
TSI_GENCS[TSIIE] are set. Then the on-chip DMA controller detects this request and
transfers data between memory space and TSI register space. After the data tranfer, DMA
DONE is asserted to clear TSI_GENCS[EOSF] automatically. This function is normally
used by DMA controller to get the conversion result from TSI_DATA[TSICNT] upon a
end-of-scan event and then refresh the channel index(TSI_DATA[TSICH]) for next
trigger.
35.4.13 Noise detection mode
The noise detection mode is used to detect power of noise. In this mode the thresholds are
incremented internally by TSI until the point that there is no noise voltage trepassing the
threshold.
The noise detection mode change the circuit configuration as shown in the following
figure. With this configuration, it is possible to detect touch with high levels of EMC
noise present. To enter this mode, set TSI_CS3[STAT_STUP] field to 1100b.
In noise detection mode the reference oscillator has the same configuration except the
output goes to Counter2 and this counter will have its maximum count set by
NSCNx2
(PS)
. This means this oscillator will setup the noise detection mode sense
duration as shown in Figure 35-5 .
The blocks of external oscillator is changed and instead of an oscillator the circuit
implements an RF amplitude detection. The threshold for this amplitude detection is set
by DVOLT register bits. Be noted There is no oscillation on external pad (just if it is
caused by external noise) in this mode.
Also the external voltage is biased by vmid voltage with a Rs series resistance.
Functional description
MKW01Z128 MCU Reference Manual, Rev. 3, 04/2016
702 Freescale Semiconductor, Inc.