C167CR_00 Datasheet, PDF (344/464 Pages) Infineon Technologies AG – 16-Bi t Single-Chip Microcont roller

C167CR
Derivatives
The Analog/Digital Converter
Channel Injection Mode
Channel Injection Mode allows the conversion of a specific analog channel (also while
the ADC is running in a continuous or auto scan mode) without changing the current
operating mode. After the conversion of this specific channel the ADC continues with the
original operating mode.
Channel Injection mode is enabled by setting bit ADCIN in register ADCON and requires
the Wait for ADDAT Read Mode (ADWR = ‘1’). The channel to be converted in this mode
is specified in bitfield CHNR of register ADDAT2.
Note: Bitfield CHNR in ADDAT2 is not modified by the A/D converter, but only the
ADRES bit field. Since the channel number for an injected conversion is not
buffered, bitfield CHNR of ADDAT2 must never be modified during the sample
phase of an injected conversion, otherwise the input multiplexer will switch to the
new channel. It is recommended to only change the channel number with no
injected conversion running.
#x
Conversion
of Channel..
# x-1
# x-2
# x-3
# x-4
# ...
Write ADDAT; # x+1
#x
ADDAT Full
# x-1
# x-2
Read ADDAT
# x+1
#x
# x-1
# x-2
Injected
Conversion
of Channel # y
ADDAT2 Full
Read ADDAT2
Channel Injection
Request
#y
Write ADDAT2
Int. Request
ADEINT
Figure 17-5 Channel Injection Example
# x-3
# x-4
# x-3
# x-4
MCA01971
User’s Manual
17-8
V3.1, 2000-03