
Enhanced Queued Analog-to-Digital Converter (EQADC)
MPC5644A Microcontroller Reference Manual, Rev. 6
1158
Freescale Semiconductor
Step Two: Configure the DMAC to handle data transfers between the CQueues/RQueues in RAM and the
CFIFOs/RFIFOs in the EQADC.
1. For transferring, set the source address of the DMAC to point to the start address of CQueue1. Set
the destination address of the DMAC to point to EQADC_CFPR1. Refer to
EQADC CFIFO Push Registers (EQADC_CFPR)
2. For receiving, set the source address of the DMAC to point to EQADC_RFPR3. Refer to
Section 25.5.2.6, EQADC Result FIFO Pop Registers (EQADC_RFPR)
. Set the destination
address of the DMAC to point to the starting address of RQueue1.
Step Three: Configure the EQADC Control Registers.
1. Configure
Section 25.5.2.8, EQADC Interrupt and DMA Control Registers (EQADC_IDCR)
.
a) Set EOQIE1 to enable the End of Queue Interrupt request.
b) Set CFFS1 and RFDS3 to configure the EQADC to generate DMA requests to push commands
into CFIFO1 and to pop result data from RFIF03.
c) Set CFINV1 to invalidate the contents of CFIFO1.
d) Set RFDE3 and CFFE1 to enable the EQADC to generate DMA requests. Command transfers
from the RAM to the CFIFO1 will start immediately.
e) Set RFOIE3 to indicate if RFIFO3 overflows.
f) Set CFUIE1 to indicate if CFIFO1 underflows.
2. Configure MODE1 to continuous-scan rising edge external trigger mode in
EQADC CFIFO Control Registers (EQADC_CFCR)
Step Four: Command transfer to ADCs and Result data reception.
When an external rising edge event occurs for CFIFO1, the EQADC automatically will begin
transferring commands from CFIFO1 when it becomes the highest priority CFIFO trying to send
commands to CBuffer1. The received results will be placed in RFIFO3 and then moved to
RQueue1 by the DMAC.
CMD
8
0
1
0
0
0
1
0
Configure peripheral device for next conversion sequence
0
etc. ...
CMD
EOQ
1
0
0
0
0
1
0
0b0011
EOQ Message
1
Fields LST, TSR, FMT, and CHANNEL_NUMBER are not showed for clarity. See
Format for the Standard Configuration
, for details.
2
MESSAGE_TAG field is only defined for read configuration commands.
Table 25-76. Example of CQueue Commands
1
(continued)
Bit #
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Bit
Name
EOQ
PA
U
S
E
REP
RESER
V
E
D
EB
BN
RESER
V
E
D
MESSAGE
TAG
ADC COMMAND
CFIFO Header
ADC Command
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...