MAXQ61HA-0000+ MAXIM [Maxim Integrated Products], MAXQ61HA-0000+ Datasheet - Page 14

• Manufacturer Part Number: MAXQ61HA-0000+
• Description: 16-Bit Microcontroller with Infrared Module
• Manufacturer: MAXIM [Maxim Integrated Products]

16-Bit Microcontroller with Infrared Module
Figure 4. External IRTXM (Modulator) Output
Figure 5. IR Capture
A special mode reduces the CPU processing burden
when performing IR learning functions. Typically, when
operating in an IR learning capacity, some number of
carrier cycles are examined for frequency determina-
tion. Once the frequency has been determined, the IR
receive function can be reduced to counting the number
of carrier pulses in the burst and the duration of the
combined mark-space time within the burst. To simplify
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IR INTERRUPT
IRV INTERVAL
IRTXPOL = 1
IRTXPOL = 0
IRCLK
IRRX PIN
IRDATA
IRTXM
IRTXM
1
IRMT
IRCAH + 1
Carrier Burst-Count Mode
CARRIER GENERATION
0
IRMT
EDGE DETECT
IRCAL + 1
1
IRCFME
0
1
0
this process, the receive burst-count mode (as enabled
by the RXBCNT bit) can be used. When RXBCNT = 0,
the standard IR receive capture functionality is in place.
When RXBCNT = 1, the IRV capture operation is dis-
abled and the interrupt flag associated with the capture
no longer denotes a capture. In the carrier burst-count
mode, the IRMT register is now used only to count quali-
fied edges. The IRIF interrupt flag (normally used to sig-
nal a capture when RXBCNT = 0) now becomes set if
CARRIER MODULATION
RESET IRV TO 0000h
1
COPY IRV TO IRMT
0000h
ON EDGE DETECT
IRV
0
IR TIMER OVERFLOW
IR INTERRUPT
IRXRL
1
IRMT
INTERRUPT TO CPU
0
IRDATA
IRMT