Enhanced Queued Analog-to-Digital Converter (EQADC)
Freescale Semiconductor
27-55
PXR40 Microcontroller Reference Manual, Rev. 1
Figure 27-42. Command Flow during EQADC operation
ADC commands sent to the on-chip CBuffers are executed in a first-in-first-out basis with exception when
the immediate conversion command function is enabled. Three types of results can be expected: data read
from an ADC register, a conversion result, or a time stamp.
NOTE
While the EQADC pops commands out from a CFIFO, it also is checking
the number of entries in the CFIFO and generating requests to fill it. The
process of pushing and popping commands to and from a CFIFO can occur
simultaneously. However, this is not true for CFIFO0 when configured to
operate in streaming mode for popping.
The
FIFO Control Unit
expects all incoming results to be shaped in a predefined Result Message format.
shows how result data flows inside the EQADC system. Results generated on the on-chip
ADCs are adjusted considering the selected resolution of the ADC and are formatted into result messages
inside the
Result Format and Calibration Sub-Block
. This result message can be routed directly to one of
the RFIFOs or to an on-chip companion module (decimation filter) via the parallel side interface. After the
data is processed by the companion module, it can be routed back to one of the RFIFOs via the side
interface with the correct format. A result message is composed of an RFIFO header and an ADC Result.
The
FIFO Control Unit
decodes the information contained in the RFIFO header to determine the RFIFO
to which the ADC result should be sent. Once in an RFIFO, the ADC result is moved to the corresponding
RQueue by the host CPU or by the DMAC as they respond to interrupt and DMA requests generated by
the EQADC. The EQADC generates these requests whenever an RFIFO has at least one entry.
Priority
CFIFOx
NOTE: x=0, 1, 2, 3, 4, 5
32 bits
CQueuey
CBuffer
Inside EQADC
FIFO Control
To
ADCs
Command Message
CFIFO Header
ADC Command
Host CPU
or
DMAC
32 bits
DMA or interrupt requests
ADC
y=0, 1, 2, 3, ...
System Memory
DMA Transaction
Done Signals
Unit
Abort
Cont
Summary of Contents for PXR4030
Page 1: ...PXR40 Microcontroller Reference Manual Devices Supported PXR4030 PXR4040 PXR40RM Rev 1 06 2011...
Page 30: ...PXR40 Microcontroller Reference Manual Rev 1 Freescale Semiconductor xxx...
Page 40: ...PXR40 Microcontroller Reference Manual Rev 1 xl Freescale Semiconductor...
Page 66: ...Memory Map PXR40 Microcontroller Reference Manual Rev 1 2 4 Freescale Semiconductor...
Page 120: ...Signal Descriptions 3 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 860: ...FlexCAN Module 24 50 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Page 1167: ...Decimation Filter Freescale Semiconductor 28 53 PXR40 Microcontroller Reference Manual Rev 1...
Page 1168: ...Decimation Filter 28 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...