Enhanced Queued Analog-to-Digital Converter (eQADC)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
Freescale Semiconductor
31-31
Preliminary
31.3.4.5
ADC0 Offset Calibration Constant Register (ADC0_OCCR)
The ADC0_OCCR contains the offset calibration constant used to fine-tune the ADC0 conversion results.
The offset constant is a signed 14-bit integer value. Refer to
Section 31.4.5.4, “ADC Calibration Feature
for details about the calibration scheme used in the eQADC.
31.4
Functional Description
The eQADC provides an interface to an on-chip ADC.
Initially, command data is contained in system memory in a user-defined data queue structure. Command
data is moved between the user-defined queues and CFIFOs by the host CPU or by the eDMA which
responds to interrupt and eDMA requests generated by the eQADC. The eQADC supports software and
hardware triggers from other modules or external pins to initiate transfers of commands from the multiple
CFIFOs to the on-chip ADC.
CFIFOs can be configured to be in single-scan or continuous-scan mode. When a CFIFO is configured to
be in single-scan mode, the eQADC scans the user-defined command queue one time. The eQADC stops
transferring commands from the triggered CFIFO after detecting the EOQ bit set in the last transfer. After
an EOQ bit is detected, software involvement is required to rearm the CFIFO so that it can detect new
trigger events.
When a CFIFO is configured for continuous-scan mode, the whole user command queue is scanned
multiple times. After the detection of an asserted EOQ bit in the last command transfer, command transfers
can continue or not depending on the mode of operation of the CFIFO.
The eQADC can also in parallel and independently of the CFIFOs receive data from the on-chip ADC into
multiple RFIFOs. Result data is moved from the RFIFOs to the user-defined result queues in system
memory by the host CPU or by the eDMA.
Offset: 0x0005
Access: Read/Write
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
0
0
OCC0
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Figure 31-19. ADC0 Offset Calibration Constant Registers (ADC0_OCCR)
Table 31-25. ADC0_OCCR Field Descriptions
Field
Description
0–1
Reserved.
OCCn
ADC0 Offset Calibration Constant. Contains the offset calibration constant used to fine-tune ADC0 conversion
results. Negative values should be expressed using the two’s complement representation.