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Chapter 24 Analog-to-Digital Converter (ADC12B16C) Block Description
MC9S12XF - Family Reference Manual, Rev.1.19
1086
Freescale Semiconductor
24.3.2.7
ATD Status Register 0 (ATDSTAT0)
This register contains the Sequence Complete Flag, overrun ags for external trigger and FIFO mode, and
the conversion counter.
Read: Anytime
Write: Anytime (No effect on (CC3, CC2, CC1, CC0))
Module Base + 0x0006
76543210
R
SCF
0
ETORF
FIFOR
CC3
CC2
CC1
CC0
W
Reset
0
00000
= Unimplemented or Reserved
Figure 24-9. ATD Status Register 0 (ATDSTAT0)
Table 24-16. ATDSTAT0 Field Descriptions
Field
Description
7
SCF
Sequence Complete Flag — This ag is set upon completion of a conversion sequence. If conversion
sequences are continuously performed (SCAN=1), the ag is set after each one is completed. This ag is cleared
when one of the following occurs:
A) Write “1” to SCF
B) Write to ATDCTL5 (a new conversion sequence is started)
C) If AFFC=1 and read of a result register
0 Conversion sequence not completed
1 Conversion sequence has completed
5
ETORF
External Trigger Overrun Flag — While in edge trigger mode (ETRIGLE=0), if additional active edges are
detected while a conversion sequence is in process the overrun ag is set. This ag is cleared when one of the
following occurs:
A) Write “1” to ETORF
B) Write to ATDCTL0,1,2,3,4, ATDCMPE or ATDCMPHT (a conversion sequence is aborted)
C) Write to ATDCTL5 (a new conversion sequence is started)
0 No External trigger over run error has occurred
1 External trigger over run error has occurred
4
FIFOR
Result Register Over Run Flag — This bit indicates that a result register has been written to before its
associated conversion complete ag (CCF) has been cleared. This ag is most useful when using the FIFO mode
because the ag potentially indicates that result registers are out of sync with the input channels. However, it is
also practical for non-FIFO modes, and indicates that a result register has been over written before it has been
read (i.e. the old data has been lost). This ag is cleared when one of the following occurs:
A) Write “1” to FIFOR
B) Write to ATDCTL0,1,2,3,4, ATDCMPE or ATDCMPHT (a conversion sequence is aborted)
C) Write to ATDCTL5 (a new conversion sequence is started)
0 No over run has occurred
1 Overrun condition exists (result register has been written while associated CCFx ag was still set)