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Combination mode 3: manchester modulation 1, Combination mode 4: manchester modulation 2, Figure 76 – Rainbow Electronics T48C862-R4 User Manual

Page 80: Figure 77

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80

T48C862-R4

4551B–4BMCU–02/03

Combination Mode 3:
Manchester Modulation 1

SSI mode 1:

8-bit shift register internal data output (SO) to the Timer 2
modulator stage

Timer 2 mode 1, 2, 3 or 4:

8-bit compare counter with 4-bit programmable prescaler

Timer 2 output mode 5:

The modulator 2 of Timer 2 modulates the SSI internal
data output to Manchester code

Figure 76.

Manchester Modulation 1

Combination Mode 4:
Manchester Modulation 2

SSI mode 1:

8-bit shift register internal data output (SO) to the Timer 2
modulator stage

Timer 2 mode 3:

8-bit compare counter and 4-bit prescaler

Timer 2 output mode 5:

The modulator 2 of Timer 2 modulates the SSI data output
to Manchester code

The 4-bit stage can be used as prescaler for the SSI to generate the stop signal for mod-
ulator 2. The SSI has a special mode to supply the prescaler with the shift clock.
The control output signal (OMSK) of the SSI is used as stop signal for the modulator.
Figure 72 shows an example for a 12-bit Manchester telegram.

Figure 77.

Manchester Modulation 2

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

0

0

0

0

0

0

0

0

1

2

3

4

0

1

2

0

Counter 2/1 = Compare Register 2/1 (= 4)

Bit 7 Bit 6

Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

SCLI

Buffer full

SIR

SO

SC

MSM

Timer 2

Mode 3

SCL

Counter 2/1

OMSK

T2O

3