93
AT90PWM216/316 [DATASHEET]
7710H–AVR–07/2013
13.8.3
Timer/Counter Register – TCNT0
The Timer/Counter Register gives direct access, both for read and write operations, to the Timer/Counter unit 8-bit
counter. Writing to the TCNT0 Register blocks (removes) the Compare Match on the following timer clock. Modify-
ing the counter (TCNT0) while the counter is running, introduces a risk of missing a Compare Match between
TCNT0 and the OCR0x Registers.
13.8.4
Output Compare Register A – OCR0A
The Output Compare Register A contains an 8-bit value that is continuously compared with the counter value
(TCNT0). A match can be used to generate an Output Compare interrupt, or to generate a waveform output on the
OC0A pin.
13.8.5
Output Compare Register B – OCR0B
The Output Compare Register B contains an 8-bit value that is continuously compared with the counter value
(TCNT0). A match can be used to generate an Output Compare interrupt, or to generate a waveform output on the
OC0B pin.
13.8.6
Timer/Counter Interrupt Mask Register – TIMSK0
Bits 7..3 – Res: Reserved Bits
These bits are reserved bits in the AT90PWM216/316 and will always read as zero.
Bit 2 – OCIE0B: Timer/Counter Output Compare Match B Interrupt Enable
When the OCIE0B bit is written to one, and the I-bit in the Status Register is set, the Timer/Counter Compare
Match B interrupt is enabled. The corresponding interrupt is executed if a Compare Match in Timer/Counter occurs,
i.e., when the OCF0B bit is set in the Timer/Counter Interrupt Flag Register – TIFR0.
Bit 1 – OCIE0A: Timer/Counter0 Output Compare Match A Interrupt Enable
When the OCIE0A bit is written to one, and the I-bit in the Status Register is set, the Timer/Counter0 Compare
Match A interrupt is enabled. The corresponding interrupt is executed if a Compare Match in Timer/Counter0
occurs, i.e., when the OCF0A bit is set in the Timer/Counter 0 Interrupt Flag Register – TIFR0.
Bit
76543210
TCNT0[7:0]
TCNT0
Read/Write
R/W
Initial Value
00000000
Bit
76543210
OCR0A[7:0]
OCR0A
Read/Write
R/W
Initial Value
00000000
Bit
76543210
OCR0B[7:0]
OCR0B
Read/Write
R/W
Initial Value
00000000
Bit
7654
3
2
1
0
––––
–
OCIE0B
OCIE0A
TOIE0
TIMSK0
Read/Write
R
R/W
Initial Value
0000
0