NXP Semiconductors MPC5566, Reference Manual

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Enhanced Queued Analog-to-Digital Converter (eQADC)
MPC5566 Microcontroller Reference Manual, Rev. 2
Freescale Semiconductor 19-47
19.4.1.2.1 Message Formats for On-Chip ADC Operation
This section describes the command/result message formats used for on-chip ADC operation.
NOTE
Although this subsection describes how the command and result messages
are formatted to communicate with the on-chip ADCs, nothing prevents the
programmer from using a different format when communicating with an
external device through the serial interface. Refer to
Section 19.4.1.2.2,
“Message Formats for External Device Operation .” Apart from the BN bit,
the ADC command of a command message can be formatted to
communicate to an arbitrary external device provided that the device returns
an RFIFO header in the format expected by the eQADC. When the FIFO
control unit receives return data message, it decodes the message tag field
and stores the 16-bit data into the corresponding RFIFO.
Conversion Command Message Format for On-Chip ADC Operation
Figure 19-26 describes the command message format for conversion commands when interfacing with the
on-chip ADCs. A conversion result is always returned for conversion commands and time stamp
information can be optionally requested. The lower byte of conversion commands is always cleared to 0
to distinguish it from configuration commands.
Address: 0x0005 Access: R/W
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
EOQ PAUSE Reserved
EB
(0b0)
BN CAL MESSAGE_TAG LST TSR FMT
CFIFO Header ADC Command
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
CHANNEL_NUMBER ADC_REG_ADDRESS
Address Field
Figure 19-26. Conversion Command Message Format for On-Chip ADC Operation