ATMEGA640 datasheet(158/436 Pages) MICROCHIP

158 / 436 page

158

ATmega640/V-1280/V-1281/V-2560/V-2561/V [DATASHEET]

DS40002211A

• Bit 7 – FOCnA: Force Output Compare for Channel A

• Bit 6 – FOCnB: Force Output Compare for Channel B

• Bit 5 – FOCnC: Force Output Compare for Channel C

The FOCnA/FOCnB/FOCnC bits are only active when the WGMn3:0 bits specifies a non-PWM mode. When writ-

ing a logical one to the FOCnA/FOCnB/FOCnC bit, an immediate compare match is forced on the waveform

generation unit. The OCnA/OCnB/OCnC output is changed according to its COMnx1:0 bits setting. Note that the

FOCnA/FOCnB/FOCnC bits are implemented as strobes. Therefore it is the value present in the COMnx1:0 bits

that determine the effect of the forced compare.

A FOCnA/FOCnB/FOCnC strobe will not generate any interrupt nor will it clear the timer in Clear Timer on Com-

pare Match (CTC) mode using OCRnA as TOP.

The FOCnA/FOCnB/FOCnB bits are always read as zero.

• Bit 4:0 – Reserved Bits

These bits are reserved for future use. For ensuring compatibility with future devices, these bits must be written to

zero when TCCRnC is written.

17.11.13 TCNT1H and TCNT1L – Timer/Counter 1

17.11.14 TCNT3H and TCNT3L – Timer/Counter 3

17.11.15 TCNT4H and TCNT4L –Timer/Counter 4

17.11.16 TCNT5H and TCNT5L –Timer/Counter 5

The two Timer/Counter I/O locations (TCNTnH and TCNTnL, combined TCNTn) give direct access, both for read

and for write operations, to the Timer/Counter unit 16-bit counter. To ensure that both the high and low bytes are

read and written 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 registers. See

“Accessing 16-bit Registers” on page 135.

Bit

(0x85)

TCNT1[15:8]

TCNT1H

(0x84)

TCNT1[7:0]

TCNT1L

Read/Write

R/WR/W

Initial Value

Bit

(0x95)

TCNT3[15:8]

TCNT3H

(0x94)

TCNT3[7:0]

TCNT3L

Read/Write

R/WR/W

Initial Value

Bit

(0xA5)

TCNT4[15:8]

TCNT4H

(0xA4)

TCNT4[7:0]

TCNT4L

Read/Write

R/WR/W

Initial Value

Bit

(0x125)

TCNT5[15:8]

TCNT5H

(0x124)

TCNT5[7:0]

TCNT5L

Read/Write

R/WR/W

Initial Value

ATMEGA640 Datasheet(PDF) 158 Page - Microchip Technology

ATMEGA640 Datasheet(HTML) 158 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL