Quantek QT1010: Difference between revisions

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==External Links==
==External Links==
[http://www.quantek-inc.com/qt1010.html QT1010 Product page at qantek-inc.com]
[http://www.quantek-inc.com/qt1010.html QT1010 Product page at qantek-inc.com]

==Tuner registers==

Indexed from 0.

{| class="wikitable"
|-
! Index
! Name
! Description
|-
| 1
| OP
| 0x00 = start tuner with programmed registers, 0x80 = set tuner to programming mode
|-
| 5
| VCOBAND
| This controls the frequency operating range of the tuner. Low 4 bits can be 0 or 4, High 4 bits can be 1,3,5,7,9.
|-
| 17
| LNA
| 0xF0 = disable LNA hardware power, used for sleep(), 0xF9 and 0xFD used to enable hardware with LNA on/off
|}

==Description of how to program the chip==



===Tuner context===

The tuner has a global context for some variables. They can be used anytime in the init and set methods.

* reg31
* reg32
* reg34
* reg34_1
* reg34_2
* reg34_3
* reg34_4
* reg34_5
* reg34_6
* reg34_7
* reg34_8
* reg37
* reg38

===Tuner Init===
This method has no arguments.

* write 0x80 to tuner register 1
* write 0x84 to tuner register 13
* write 0xB4 to tuner register 14* (or 0xB7 might work better on some older devices)
* write 0x23 to tuner register 42
* write 0xDC to tuner register 44
* write 0x40 to tuner register 37
* write 0x00 to tuner register 30
* write 0x81 to tuner register 30

* loop 30 times
** read tuner register 37 into reg37
** if reg37 bit 8 is set
*** break out of loop

* read tuner register 37 into reg37
* write 0x00 to tuner register 30
* write 0x23 to tuner register 42
* write 0x70 to tuner register 43
* write 0x08 to tuner register 38
* write 0x00 to tuner register 30
* write 0x82 to tuner register 30

* loop 30 times
** read tuner register 38 into reg38
** if reg38 bit 5 is set
*** break out of loop

* read tuner register 38 into reg38
* write 0x00 to tuner register 30
* write 0x14 to tuner register 5
* write 0x44 to tuner register 6
* write 0x28 to tuner register 7
* write 0x0B to tuner register 8
* write 0xFD to tuner register 17* (this can be 0x0D in some cases)
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x0D to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30

* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* write 0x40 to tuner register 6
* write 0xF0 to tuner register 22
* write 0x38 to tuner register 2
* write 0x19 to tuner register 3
* write 0x20 to tuner register 31
* write 0xE0 to tuner register 32
* write 0x00 to tuner register 30
* write 0x84 to tuner register 30

* loop 30 times
** read tuner register 31 into reg31
** if register 31 bit 7 is set
*** break out of loop

* read tuner register 31 into reg31
* read tuner register 32 into reg32
* write 0x00 to tuner register 30
* write 0x3F to tuner register 2
* write 0x53 to tuner register 33
* read tuner register 33 into reg33
* write 0xFD to tuner register 17* (this can be 0x0D in some cases)
* write 0x34 to tuner register 5
* write 0x44 to tuner register 6
* write 0x31 to tuner register 7
* write 0x08 to tuner register 8
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30

* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34_1
* write 0x32 to tuner register 7
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30

* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34_2
* write 0x33 to tuner register 7
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30


* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34_3
* write 0x34 to tuner register 7
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30

* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34_4
* write 0x35 to tuner register 7
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30


* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34_5
* write 0x36 to tuner register 7
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30

* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34_6
* write 0x37 to tuner register 7
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30


* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34_7
* write 0x38 to tuner register 7
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30

* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34_8
* write 0x39 to tuner register 7
* write 0xD0 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30

* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0xD0 to tuner register 30
* read tuner register 34 into reg34

=== Tuner set frequency ===

The frequency set method has one sub-method and one subsub-method.

==== set_frequency ====

This method has the frequency argument, called freq and in Hz.

* call set_parameters with freq and command equal to tune
* if reg35 equal to 0xE0
** call set_parameters with freq and command equal to tune_next
* if reg35 equal to 0xFF
** call set_parameters with freq and command equal to 3
* if reg34 equal to 0xFF
** call set_parameters with freq and command equal to 1

==== set_parameters ====
arguments freq and command

* call calculate_parameters with freq and command
* write 0x80 to tuner register 1
* write 0x3F to tuner register 2

* if command is equal to tune_next
** if reg5 is less then 0x74
*** set reg5_1 to reg_5 plus 0x20

* write reg5_1 to tuner register 5
* write 0x44 to tuner register 6
* write freq_slot2 to tuner register 7
* write freq_slot1 to tuner register 8
* write freq_slot4 to tuner register 9
* write freq_slot5 to tuner register 10
* write freq_slot6 to tuner register 11
* write 0xE1 to tuner register 12
* write freq_slot7 to tuner register 26
* write 0x00 to tuner register 27
* write freq_slot8 to tuner register 28
* write 0xFD to tuner register 17*
* write 0x91 to tuner register 18*

* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1
* write 0x80 to tuner register 1

* if reg5_1 is equal to 0x34
** if freq_slot12 is larger equal to 0xF0
*** if freq_slot12 is less equal to 0xFA
**** write freq_slot12 minus 0x20 into freq_slot12
*** else
**** write 0xDA into freq_slot12
** else
*** write 0xD0 into freq_slot12
** write freq_slot12 into tmp_var1
* else
** write 0xD0 into tmp_var1

* write tmp_var1 to tuner register 34
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 30

* loop 30 times
** read tuner register 34
** if register 34 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* read tuner register 34 into reg34
* if reg34 is less equal to 0xFE
** write reg34 plus 1 to tuner register 34
* read tuner register 5 into reg5
* read tuner register 34 into reg34
* write 0xD0 to tuner register 35
* write 0x00 to tuner register 30
* write 0xE0 to tuner register 30

* loop 30 times
** read tuner register 35
** if register 35 bit 6 is set
*** break out of loop

* read tuner register 35 into reg35
* write 0x00 to tuner register 30
* write 0xD0 to tuner register 36
* write 0x00 to tuner register 30
* write 0xF0 to tuner register 30

* loop 30 times
** read tuner register 36
** if register 36 bit 6 is set
*** break out of loop

* write 0x00 to tuner register 30
* write 0x7F to tuner register 20
* write 0x7F to tuner register 21

* if command is equal to tune_next
** if reg5 is less equalt to 0x74
*** write reg5 minus 4 into reg5_3
* write reg5_3 to tuner register 5
* write 0x00 to tuner register 6
* write 0x1F to tuner register 21
* write 0xFF to tuner register 22
* write 0xFF to tuner register 24

* if reg31 is greater equal to 0x50
** write 0x50 into reg31
* if reg32 is greater equal to 0x12
** write 0x12 into reg32

* write reg31 plus freq_slot10 to tuner register 31
* write reg32 plus freq_slot11 to tuner register 32
* write reg33 to tuner register 33
* write reg37 to tuner register 37
* write reg38 to tuner register 38

* write 0x96 to tuner register 0
* write 0x00 to tuner register 2
* write 0x00 to tuner register 1

==== calculate_parameters ====
Not complete yet*

arguments freq (in Hz) and command

* if freq is less then 60000000 or greater then 900000000
** return error

* if command is equal to tune_next
** write g_prev_command to cmd_tmp
* else
** write command to g_prev_command

* write 36125000 to IF
* write 1232000000 to X
* write 920000000 to Y
* write ((freq + X) divided by 4) plus 500000) to Z
* write (1000000 * Z) divided by 1000000 to T1
* write (4000000* Z) divided by 1000000 - Y - freq to T2
* write (4000000* Z) divided by 1000000 - Y - freq - IF to T3
* write T3 divided by 4000000 to T4
* write T3 divided by 4 to T5
* write T1 modulus 8000000 divided by 1000000 to T6
* write (((T5 plus 15777216 multiplied by T4) multiplied by 16) plus 500000) divided by 1000000 to T7

* write T4 to freq_slot5
* write T7 truncated to 8 bits to freq_slot7
* write 2 multiplied by (T7 shifted left 8) + 137 to freq_slot8

===Tuner On/Off===
This method has 1 argument, curr set to either 0 or 1

==== set_tuner_off ====

* write 0x80 to tuner register 1

* if curr is 1
** read tuner register 17 into tmp
** write tmp logical and 0xF0 into tmp
** write tmp to tuner register 17
* write 0x7F to tuner register 2
* read tuner register 5 into tmp
* write tmp logical or 0xF into tmp
* write tmp to tuner register 5
* write 0xFF to tuner register 6

* write 0x00 to tuner register 1

==== set_tuner_on ====

* write 0x80 to tuner register 1

* write 0x00 to tuner register 2
* read tuner register 5 into tmp
* write tmp logical and 0xF0 into tmp
* write tmp to tuner register 5
* write 0x00 to tuner register 6

* write 0x00 to tuner register 1
[[Category:Tuners]]
[[Category:Tuners]]

Latest revision as of 11:56, 2 March 2010

The Quantek QT1010 is a wideband tuner chip.

Features

  • 48MHz-860MHz frequency range (bands I, II, III, IV).
  • 30MHz-60MHz IF output range.
  • NTSC, PAL, SECAM broadcast formats.
  • DVB-C, DVB-T, ATSC and ISDB-T support.

External Links

QT1010 Product page at qantek-inc.com

Tuner registers

Indexed from 0.

Index Name Description
1 OP 0x00 = start tuner with programmed registers, 0x80 = set tuner to programming mode
5 VCOBAND This controls the frequency operating range of the tuner. Low 4 bits can be 0 or 4, High 4 bits can be 1,3,5,7,9.
17 LNA 0xF0 = disable LNA hardware power, used for sleep(), 0xF9 and 0xFD used to enable hardware with LNA on/off

Description of how to program the chip

Tuner context

The tuner has a global context for some variables. They can be used anytime in the init and set methods.

  • reg31
  • reg32
  • reg34
  • reg34_1
  • reg34_2
  • reg34_3
  • reg34_4
  • reg34_5
  • reg34_6
  • reg34_7
  • reg34_8
  • reg37
  • reg38

Tuner Init

This method has no arguments.

  • write 0x80 to tuner register 1
  • write 0x84 to tuner register 13
  • write 0xB4 to tuner register 14* (or 0xB7 might work better on some older devices)
  • write 0x23 to tuner register 42
  • write 0xDC to tuner register 44
  • write 0x40 to tuner register 37
  • write 0x00 to tuner register 30
  • write 0x81 to tuner register 30
  • loop 30 times
    • read tuner register 37 into reg37
    • if reg37 bit 8 is set
      • break out of loop
  • read tuner register 37 into reg37
  • write 0x00 to tuner register 30
  • write 0x23 to tuner register 42
  • write 0x70 to tuner register 43
  • write 0x08 to tuner register 38
  • write 0x00 to tuner register 30
  • write 0x82 to tuner register 30
  • loop 30 times
    • read tuner register 38 into reg38
    • if reg38 bit 5 is set
      • break out of loop
  • read tuner register 38 into reg38
  • write 0x00 to tuner register 30
  • write 0x14 to tuner register 5
  • write 0x44 to tuner register 6
  • write 0x28 to tuner register 7
  • write 0x0B to tuner register 8
  • write 0xFD to tuner register 17* (this can be 0x0D in some cases)
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x0D to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30
  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • write 0x40 to tuner register 6
  • write 0xF0 to tuner register 22
  • write 0x38 to tuner register 2
  • write 0x19 to tuner register 3
  • write 0x20 to tuner register 31
  • write 0xE0 to tuner register 32
  • write 0x00 to tuner register 30
  • write 0x84 to tuner register 30
  • loop 30 times
    • read tuner register 31 into reg31
    • if register 31 bit 7 is set
      • break out of loop
  • read tuner register 31 into reg31
  • read tuner register 32 into reg32
  • write 0x00 to tuner register 30
  • write 0x3F to tuner register 2
  • write 0x53 to tuner register 33
  • read tuner register 33 into reg33
  • write 0xFD to tuner register 17* (this can be 0x0D in some cases)
  • write 0x34 to tuner register 5
  • write 0x44 to tuner register 6
  • write 0x31 to tuner register 7
  • write 0x08 to tuner register 8
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30
  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34_1
  • write 0x32 to tuner register 7
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30
  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34_2
  • write 0x33 to tuner register 7
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30


  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34_3
  • write 0x34 to tuner register 7
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30
  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34_4
  • write 0x35 to tuner register 7
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30


  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34_5
  • write 0x36 to tuner register 7
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30
  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34_6
  • write 0x37 to tuner register 7
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30


  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34_7
  • write 0x38 to tuner register 7
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30
  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34_8
  • write 0x39 to tuner register 7
  • write 0xD0 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30
  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0xD0 to tuner register 30
  • read tuner register 34 into reg34

Tuner set frequency

The frequency set method has one sub-method and one subsub-method.

set_frequency

This method has the frequency argument, called freq and in Hz.

  • call set_parameters with freq and command equal to tune
  • if reg35 equal to 0xE0
    • call set_parameters with freq and command equal to tune_next
  • if reg35 equal to 0xFF
    • call set_parameters with freq and command equal to 3
  • if reg34 equal to 0xFF
    • call set_parameters with freq and command equal to 1

set_parameters

arguments freq and command

  • call calculate_parameters with freq and command
  • write 0x80 to tuner register 1
  • write 0x3F to tuner register 2
  • if command is equal to tune_next
    • if reg5 is less then 0x74
      • set reg5_1 to reg_5 plus 0x20
  • write reg5_1 to tuner register 5
  • write 0x44 to tuner register 6
  • write freq_slot2 to tuner register 7
  • write freq_slot1 to tuner register 8
  • write freq_slot4 to tuner register 9
  • write freq_slot5 to tuner register 10
  • write freq_slot6 to tuner register 11
  • write 0xE1 to tuner register 12
  • write freq_slot7 to tuner register 26
  • write 0x00 to tuner register 27
  • write freq_slot8 to tuner register 28
  • write 0xFD to tuner register 17*
  • write 0x91 to tuner register 18*
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • write 0x80 to tuner register 1
  • if reg5_1 is equal to 0x34
    • if freq_slot12 is larger equal to 0xF0
      • if freq_slot12 is less equal to 0xFA
        • write freq_slot12 minus 0x20 into freq_slot12
      • else
        • write 0xDA into freq_slot12
    • else
      • write 0xD0 into freq_slot12
    • write freq_slot12 into tmp_var1
  • else
    • write 0xD0 into tmp_var1
  • write tmp_var1 to tuner register 34
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 30
  • loop 30 times
    • read tuner register 34
    • if register 34 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • read tuner register 34 into reg34
  • if reg34 is less equal to 0xFE
    • write reg34 plus 1 to tuner register 34
  • read tuner register 5 into reg5
  • read tuner register 34 into reg34
  • write 0xD0 to tuner register 35
  • write 0x00 to tuner register 30
  • write 0xE0 to tuner register 30
  • loop 30 times
    • read tuner register 35
    • if register 35 bit 6 is set
      • break out of loop
  • read tuner register 35 into reg35
  • write 0x00 to tuner register 30
  • write 0xD0 to tuner register 36
  • write 0x00 to tuner register 30
  • write 0xF0 to tuner register 30
  • loop 30 times
    • read tuner register 36
    • if register 36 bit 6 is set
      • break out of loop
  • write 0x00 to tuner register 30
  • write 0x7F to tuner register 20
  • write 0x7F to tuner register 21
  • if command is equal to tune_next
    • if reg5 is less equalt to 0x74
      • write reg5 minus 4 into reg5_3
  • write reg5_3 to tuner register 5
  • write 0x00 to tuner register 6
  • write 0x1F to tuner register 21
  • write 0xFF to tuner register 22
  • write 0xFF to tuner register 24
  • if reg31 is greater equal to 0x50
    • write 0x50 into reg31
  • if reg32 is greater equal to 0x12
    • write 0x12 into reg32
  • write reg31 plus freq_slot10 to tuner register 31
  • write reg32 plus freq_slot11 to tuner register 32
  • write reg33 to tuner register 33
  • write reg37 to tuner register 37
  • write reg38 to tuner register 38
  • write 0x96 to tuner register 0
  • write 0x00 to tuner register 2
  • write 0x00 to tuner register 1

calculate_parameters

Not complete yet*

arguments freq (in Hz) and command

  • if freq is less then 60000000 or greater then 900000000
    • return error
  • if command is equal to tune_next
    • write g_prev_command to cmd_tmp
  • else
    • write command to g_prev_command
  • write 36125000 to IF
  • write 1232000000 to X
  • write 920000000 to Y
  • write ((freq + X) divided by 4) plus 500000) to Z
  • write (1000000 * Z) divided by 1000000 to T1
  • write (4000000* Z) divided by 1000000 - Y - freq to T2
  • write (4000000* Z) divided by 1000000 - Y - freq - IF to T3
  • write T3 divided by 4000000 to T4
  • write T3 divided by 4 to T5
  • write T1 modulus 8000000 divided by 1000000 to T6
  • write (((T5 plus 15777216 multiplied by T4) multiplied by 16) plus 500000) divided by 1000000 to T7
  • write T4 to freq_slot5
  • write T7 truncated to 8 bits to freq_slot7
  • write 2 multiplied by (T7 shifted left 8) + 137 to freq_slot8

Tuner On/Off

This method has 1 argument, curr set to either 0 or 1

set_tuner_off

  • write 0x80 to tuner register 1
  • if curr is 1
    • read tuner register 17 into tmp
    • write tmp logical and 0xF0 into tmp
    • write tmp to tuner register 17
  • write 0x7F to tuner register 2
  • read tuner register 5 into tmp
  • write tmp logical or 0xF into tmp
  • write tmp to tuner register 5
  • write 0xFF to tuner register 6
  • write 0x00 to tuner register 1

set_tuner_on

  • write 0x80 to tuner register 1
  • write 0x00 to tuner register 2
  • read tuner register 5 into tmp
  • write tmp logical and 0xF0 into tmp
  • write tmp to tuner register 5
  • write 0x00 to tuner register 6
  • write 0x00 to tuner register 1