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Enhanced Queued Analog-to-Digital Converter (EQADC)
MPC5644A Microcontroller Reference Manual, Rev. 6
Freescale Semiconductor
1087
information about the status of the CBuffers (BUSY fields), and result data. The BUSY fields are needed
to inform the EQADC about when it is appropriate to transfer commands to the external CBuffers.
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
RESERVED
MESSAGE_TAG
BUSY1
BUSY0
RFIFO Header
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
ADC_RESULT
ADC Result
Figure 25-57. Result Message Format for External Device Operation
Table 25-60. Result Message Format for External Device Operation field description
Field
Description
8-11
MESSAGE_TAG
[0:3]
MESSAGE_TAG Field
Refer to
Section , Conversion Command Format for the Standard Configuration
.
12-13
BUSY1[0:1]
BUSY Status field
The BUSY fields indicate if the external device can receive more commands.
shows how these two bits are encoded. When an external device cannot accept any more
new commands, it must set BUSYx to a value indicating “Do not send commands” in the
returning message. The BUSY fields of values 0b10 and 0b10 can be freely encoded by the
external device to allow visibility of the status of the external CBuffers for debug, they could
indicate the number of entries in a external CBuffer for example.
Note:
After reset, the EQADC always assumes that the external CBuffers are full and cannot
receive commands.
14-15
BUSY0[0:1]
BUSY Status field
The BUSY fields indicate if the external device can receive more commands.
shows how these two bits are encoded. When an external device cannot accept any more
new commands, it must set BUSYx to a value indicating “Do not send commands” in the
returning message. The BUSY fields of values 0b10 and 0b10 can be freely encoded by the
external device to allow visibility of the status of the external CBuffers for debug, they could
indicate the number of entries in a external CBuffer for example.
Note:
After reset, the EQADC always assumes that the external CBuffers are full and cannot
receive commands.
16-31
ADC_RESULT
[0:15]
ADC RESULT Field
ADC_RESULT is the result data received from the external device or on-chip ADC. This can
be the result of a conversion command, data requested via a read configuration command,
or time stamp value. The ADC_RESULT of any incoming message with a Null Message tag
will be ignored. When the MESSAGE_TAG is for an RFIFO, the EQADC extracts the 16-bit
ADC_RESULT from the raw message and stores it into the appropriate RFIFO.
Summary of Contents for MPC5644A
Page 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
Page 24: ...MPC5644A Microcontroller Reference Manual Rev 6 24 Freescale Semiconductor...
Page 26: ...MPC5644A Microcontroller Reference Manual Rev 6 26 Freescale Semiconductor...
Page 52: ...Introduction MPC5644A Microcontroller Reference Manual Rev 6 52 Freescale Semiconductor...
Page 56: ...Memory Map MPC5644A Microcontroller Reference Manual Rev 6 56 Freescale Semiconductor...
Page 1228: ...Decimation Filter MPC5644A Microcontroller Reference Manual Rev 6 1228 Freescale Semiconductor...
Page 1440: ...FlexCAN Module MPC5644A Microcontroller Reference Manual Rev 6 1440 Freescale Semiconductor...