MC9S12KG128_10 Datasheet, PDF (227/606 Pages) Freescale Semiconductor, Inc – HCS12 Microcontrollers

Chapter 7 Analog-to-Digital Converter (ATD10B16CV3) Block Description
Table 7-6. ATDCTL2 Field Descriptions
Field
7
ADPU
6
AFFC
5
AWAI
4
ETRIGLE
3
ETRIGP
2
ETRIGE
1
ASCIE
0
ASCIF
Description
ATD Power Down — This bit provides on/off control over the ATD10B16C block allowing reduced MCU power
consumption. Because analog electronic is turned off when powered down, the ATD requires a recovery time
period after ADPU bit is enabled.
0 Power down ATD
1 Normal ATD functionality
ATD Fast Flag Clear All
0 ATD flag clearing operates normally (read the status register ATDSTAT1 before reading the result register
to clear the associate CCF flag).
1 Changes all ATD conversion complete flags to a fast clear sequence. Any access to a result register will
cause the associate CCF flag to clear automatically.
ATD Power Down in Wait Mode — When entering Wait Mode this bit provides on/off control over the
ATD10B16C block allowing reduced MCU power. Because analog electronic is turned off when powered down,
the ATD requires a recovery time period after exit from Wait mode.
0 ATD continues to run in Wait mode
1 Halt conversion and power down ATD during Wait mode
After exiting Wait mode with an interrupt conversion will resume. But due to the recovery time the result of
this conversion should be ignored.
External Trigger Level/Edge Control — This bit controls the sensitivity of the external trigger signal. See
Table 7-7 for details.
External Trigger Polarity — This bit controls the polarity of the external trigger signal. See Table 7-7 for
details.
External Trigger Mode Enable — This bit enables the external trigger on one of the AD channels or the ETRIG
input as described in Table 7-5. If external trigger source is one of the AD channels, the digital input buffer of
this channel is enabled. The external trigger allows to synchronize the start of conversion with external events.
0 Disable external trigger
1 Enable external trigger
Note: If using one of the ATD channel as external trigger (ETRIGSEL = 0) the conversion results for this
channel have no meaning while external trigger mode is enabled.
ATD Sequence Complete Interrupt Enable
0 ATD Sequence Complete interrupt requests are disabled.
1 ATD Interrupt will be requested whenever ASCIF = 1 is set.
ATD Sequence Complete Interrupt Flag — If ASCIE = 1 the ASCIF flag equals the SCF flag (see
Section 7.3.2.7, “ATD Status Register 0 (ATDSTAT0)”), else ASCIF reads zero. Writes have no effect.
0 No ATD interrupt occurred
1 ATD sequence complete interrupt pending
Table 7-7. External Trigger Configurations
ETRIGLE
0
0
1
1
ETRIGP
0
1
0
1
External Trigger Sensitivity
Falling Edge
Ring Edge
Low Level
High Level
MC9S12KG128 Data Sheet, Rev. 1.16
Freescale Semiconductor
227