Freescale Semiconductor MC9S12ZVM series, Справочное руководство

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Chapter 9 Analog-to-Digital Converter (ADC12B_LBA_V1)
MC9S12ZVM Family Reference Manual Rev. 1.3
352 Freescale Semiconductor
9.5.3.2.1 Introduction of The Command Sequence List (CSL) Format
A Command Sequence List (CSL) contains up to 64 conversion commands. A user selectable number of
successive conversion commands in the CSL can be grouped as a command sequence. This sequence of
conversion commands is successively executed by the ADC at the occurrence of a Trigger Event. The
commands of a sequence are successively executed until an “End Of Sequence” or “End Of List”
command type identifier in a command is detected (command type is coded via bits CMD_SEL[1:0]). The
number of successive conversion commands that belong to a command sequence and the number of
command sequences inside the CSL can be freely defined by the user and is limited by the 64 conversion
commands a CSL can contain. A CSL must contain at least one conversion command and one “end of list”
command type identifier. The minimum number of command sequences inside a CSL is zero and the
maximum number of command sequences is 63. A command sequence is defined with bits
CMD_SEL[1:0] in the register ADCCMD_M by defining the end of a conversion sequence. The
Figure 9-29 and Figure 9-30 provides examples of a CSL.
Figure 9-29. Example CSL with sequences and an “End Of List” command type identifier
Command_1
Command_2
Command_3
Command_4
Command_5
Command_6
Command_7
Command_8
Command_9
Command_10
Command_11
Command_12
Command_13
CSL_0/1
End Of Sequence
normal conversion
Command Coding Information
normal conversion
normal conversion
normal conversion
normal conversion
normal conversion
0 0
0 0
0 0
0 0
0 0
0 1
0 0
0 0
0 1
0 0
0 0
1 1
0 0
CMD_SEL[1:0]
done by bits
End Of Sequence
normal conversion
normal conversion
End Of List
normal conversion
normal conversion
}
Sequence_1
}
Sequence_2
}
Sequence_3
Waiting for trigger
to proceed
Waiting for trigger
to proceed
Waiting for trigger
to proceed
Wait for RSTA or
LDOK+RSTA