XC886/888CLM
Analog-to-Digital Converter
User’s Manual
16-25
V1.3, 2010-02
ADC, V 1.0
16.4.8.2
Channel Interrupts
The channel interrupts occur when a conversion is completed and the selected limit
checking condition is met. As a result, only one channel interrupt can be activated at a
time. An interrupt can be triggered according to the limit checking result by comparing
the conversion result with two selectable boundaries for each channel.
Figure 16-14 Channel Interrupt Overview
The limit checking unit uses two boundaries (BOUND0 and BOUND1) to compare with
the conversion result. With these two boundaries, the conversion result space is split into
three areas:
•
Area I: The conversion result is below both boundaries.
•
Area II: The conversion result is between the two boundaries, or is equal to one of
the boundaries.
•
Area III: The conversion result is above both boundaries.
After a conversion has been completed, a channel interrupt can be triggered according
to the following conditions (selected by the limit check control bit field LCC):
•
LCC = 000: No trigger, the channel interrupt is disabled.
•
LCC = 001: A channel interrupt is generated if the conversion result is not in area I.
•
LCC = 010: A channel interrupt is generated if the conversion result is not in area II.
•
LCC = 011: A channel interrupt is generated if the conversion result is not in area III.
•
LCC = 100: A channel interrupt is always generated (regardless of the boundaries).
•
LCC = 101: A channel interrupt is generated if the conversion result is in area I.
•
LCC = 110: A channel interrupt is generated if the conversion result is in area II.
•
LCC = 111: A channel interrupt is generated if the conversion result is in area III.
The channel-specific interrupt node pointer CHINPx (x = 0 - 7) selects the service
request output (SR[1:0]) that will be activated upon a channel interrupt trigger.
See
.
to SR0
to SR1
arbiter
analog
part
request
sources
conversion finished
result
channel number
limit
check
unit
bounda-
ries
channel interrupt
trigger
channel
interrupt
routing
channel number
BOUND0
BOUND1
*