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Timer 2 output mode 4, Timer 2 output mode 5, Timer 2 output mode 7 – Rainbow Electronics ATAR862-8 User Manual

Page 49: Atar862-8, Timer 2 output mode 4 biphase modulator, Figure 47, Timer 2 output mode 5 manchester modulator, Figure 48

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49

ATAR862-8

4589B–4BMCU–02/03

Timer 2 Output Mode 4

Biphase Modulator:

Timer 2 Modulates the SSI Internal Data Output (SO) to Biphase

Code.

Figure 47.

Biphase Modulation

Timer 2 Output Mode 5

Manchester Modulator:

Timer 2 Modulates the SSI internal data output (SO) to

Manchester code

Figure 48.

Manchester Modulation

Timer 2 Output Mode 7

In this mode the timer overflow defines the period and the compare register defines the
duty cycle. During one period only the first compare match occurrence is used to toggle
the timer output flip-flop, until the overflow all further compare match are ignored. This
avoids the situation that changing the compare register causes the occurrence of sev-
eral compare match during one period. The resolution at the pulse-width modulation
Timer 2 mode 1 is 12-bit and all other Timer 2 modes are 8-bit.

TOG2

SC

SO

T2O

0

0

0

0

0

0

1

1

0

1

0

1

1

1

1

1

8-bit SR-Data

Bit 7

Bit 0

Data: 00110101

TOG2

SC

SO

T2O

0

0

0

0

0

1

1

0

1

0

1

1

1

1

1

8-bit SR-Data

Bit 7

Bit 0

0

Bit 7

Bit 0

Data: 00110101