142
7593L–AVR–09/12
AT90USB64/128
15.10.12 OCR3AH and OCR3AL – Output Compare Register 3 A
15.10.13 OCR3BH and OCR3BL – Output Compare Register 3 B
15.10.14 OCR3CH and OCR3CL – Output Compare Register 3 C
The Output Compare Registers contain a 16-bit value that is continuously compared with the
counter value (TCNTn). A match can be used to generate an Output Compare interrupt, or to
generate a waveform output on the OCnx pin.
The Output Compare Registers are 16-bit in size. To ensure that both the high and low bytes are
written simultaneously when the CPU writes to these registers, the access is performed using an
8-bit temporary High Byte Register (TEMP). This temporary register is shared by all the other
15.10.15 ICR1H and ICR1L – Input Capture Register 1
15.10.16 ICR3H and ICR3L – Input Capture Register 3
The Input Capture is updated with the counter (TCNTn) value each time an event occurs on the
ICPn pin (or optionally on the Analog Comparator output for Timer/Counter1). The Input Capture
can be used for defining the counter TOP value.
The Input Capture Register is 16-bit in size. To ensure that both the high and low bytes are read
simultaneously when the CPU accesses these registers, the access is performed using an 8-bit
temporary High Byte Register (TEMP). This temporary register is shared by all the other 16-bit
Bit
7
65
43
21
0
OCR3A[15:8]
OCR3AH
OCR3A[7:0]
OCR3AL
Read/write
R/W
Initial value
00
Bit
7
65
43
21
0
OCR3B[15:8]
OCR3BH
OCR3B[7:0]
OCR3BL
Read/write
R/W
Initial value
00
Bit
7
65
43
21
0
OCR3C[15:8]
OCR3CH
OCR3C[7:0]
OCR3CL
Read/write
R/W
Initial value
00
Bit
7
65
43
21
0
ICR1[15:8]
ICR1H
ICR1[7:0]
ICR1L
Read/write
R/W
Initial value
00
Bit
7
65
43
21
0
ICR3[15:8]
ICR3H
ICR3[7:0]
ICR3L
Read/write
R/W
Initial value
00