MT312C ZARLINK [Zarlink Semiconductor Inc], MT312C Datasheet - Page 31

• Manufacturer Part Number: MT312C
• Description: Satellite Channel Decoder
• Manufacturer: ZARLINK [Zarlink Semiconductor Inc]

For this example, the DiSEqC™ frequency =
For a 10MHz crystal, the tone frequency range is from 9.8kHz with DISEQC RATIO = 255 to 250kHz with
DISEQC RATIO = 10. A lower value than 10 causes the tone frequency to become unstable, until the DISEQC
RATIO = 0, the default, value giving a 22kHz tone frequency. This range is not guaranteed, the maximum tone
frequency should be used with caution.
5.2.3 DiSEqC™ Instruction (R/W). Register 36 (R/W)
Up to eight instruction data bytes are first loaded into a bank of registers through this register. The 2-wire
automatic register address incrementing is turned off during this loading by setting B7: IAI = 1 in RADD,
(register address). The number of bytes (less one) must be defined in the DiSEqC™ instruction register
DISEQC MODE[5:3].
When the DiSEqCTM instruction data bytes have been loaded, set DISEQC MODE[2:0] = 4. At the same time
program DISEQC MODE[5:3] as required. The instruction data is modulated onto the 22kHz signal and output
from the DISEQC[0] pin.
An interrupt is generated 16ms after all the data bytes have been sent and the MT312 then resets DISEQC
MODE[5:0] to zero, see Figure 19 on page 33.
5.2.4 DiSEqC™ 2 Control 1. Registers 121 (R/W)
B7-6:
B7:6
B5:
B4:
DISEQC INSTR
DISEQC2
CTRL1
NAME
NAME
i.e. DISEQC MODE[5:3] = (number of bytes in the DiSEqC™ instruction) - 1
MIN TONE PER
are for controlling (or fine tuning) the DiSEqC™ 2 receive algorithm.
Send extended pulse to the Status pin 52. This is a test or diagnostics bit. If it is set to 1, then the
cleaned up and extended pulse stream is sent to the status pin so that it can be recorded or observed.
DiSEqC™ 2 Reset only the DiSEqCTM 2 receive module. Automatically set low again after use.
ADR
ADR
121
36
Minimum Tone Period.
B7
B7
B7-6:
00
01
10
11
B6
B6
-------------- -
4*125
11E6
DISEQC Instruction [7:0]
DISEQC2 CTRL1[7:0]
B5
B5
3.125 * DISEQC RATIO
2.875 * DISEQC RATIO
2.75 * DISEQC RATIO
3.0 * DISEQC RATIO
= 22kHz.
MIN TONE PER
B4
B4
B3
B3
DiSEqC Control
B2
B2
B1
B1
B0
B0
R/W
R/W
MT312
hex
hex
Def
Def
00
00
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