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Daewoo DSD-9255E Service Manual

Manual is about: Digital Satellite reciever

Summary of DSD-9255E

  • Page 1

    S/m no. : dsd9255m02 ✔ caution : in this manual, some parts can be changed for improving, their performance without notice in the parts list. So, if you need the latest parts information,please refer to ppl(parts price list) in service information center (http://svc.Dwe.Co.Kr). Daewoo electronics co...

  • Page 2

    General information............................................................................................2 circuit operation manual .............................................................................................7 fixing errors ........................................................

  • Page 3: General Information

    2 general information digital satellite receiver is easy to use, and allows you to watch digital programs broadcasted via satellite. This instruction manual will guide you through the initial installation of your receiver. It also describes how to take full advantage of a wide range of features that...

  • Page 4

    3 general information for your safety • allow clear space of more than 10 cm from the top, back and both sides for sufficient ventilation. • do not cover the digital satellite receiver nor place it on a unit that emits heat. • use a soft cloth and a mild solution of washing liquid to clean the casin...

  • Page 5

    4 general information remote control switches between the operational mode and stand-by mode of the receiver switches between tv and av mode used for various functions on some menu displays the menu on the screen change channel, or moves to the next higher or lower item in the menu adjusts the volum...

  • Page 6

    5 general information front panel rear panel to switch on the receiver or to switch standby. To access the programming menus. To display channel list in viewing mode or to enter the programming parameters. 100~240v power input (optional function) rf modulator (optional function) connect to tv and vc...

  • Page 7

    6 general information product specification transmission standards lnb/tuner input system resources video decoder audio decoder power supply rear panel interfaces remocon transmitter dvb, mpeg2 connector iec 169-24, female-type input frequency 950 ~ 2150mhz demodulation 2 msps ~ 35msps code rate qps...

  • Page 8

    7 circuit operation manual 1. Block diagram d s d- 9230 e block diagram d s d - 9280m block diagram cpu (sti5518) audio d/a flash rom (16mbit) sdram (64mbit) television satellite dish tuner a/d 6bit dual link ic qpsk fec tv scart rca r s -232 port video audio front smps +5v +3.3v +12v +30v + 22v + 1...

  • Page 9

    8 circuit operation manual 2. Interface (1) remote controller interface " power " custom code : e8 h data code : 15 h key no key name custom code(h) data code(h) custom code(b) data code(b) k01 1 e8 h 01 h 0001 0111 1000 0000 k02 2 e8 h 02 h 0001 0111 0100 0000 k03 3 e8 h 03 h 0001 0111 1100 0000 k0...

  • Page 10

    9 circuit operating manual key no key name custom code(h) data code(h) custom code(b) data code(b) k14 info e8 h 21 h 0001 0111 1000 0100 k15 pr e8 h 17 h 0001 0111 1110 1000 k16 pr e8 h 18 h 0001 0111 0001 1000 k17 0 e8 h 00 h 0001 0111 0000 0000 k18 9 e8 h 09 h 0001 0111 1001 0000 k19 e8 h 12 h 00...

  • Page 11

    10 circuit operation manual (1) structure sti5518 is a 1 chip including 32bit risc cpu, a/v demux, video encoder, multi pio and cache ram for the use o dvb and dss set top. Followings are summary of distinctive features of each block. Enhanced capability with 32bit vl-risc cpu core of 81mhz clock. S...

  • Page 12

    11 circuit operation manual (2) reset section. If the low signal is read by sti5518 reset pin, the register value of all sti5518 will be initialized. There must be at least of 8 clock (37nsec) of reset time. (3) clock section. Sti5518 has two pll inside. Operative clocks are made by external clock w...

  • Page 13

    12 circuit operation manual this section only provides summaries of individual function of each port. Further discussion will be followed in individual port section. I 2 c_data (pio1_0) i 2 c_clk (pio1_2) used for the transmission of serial and control of tuner, ci-max, av switch and rf modulator. C...

  • Page 14

    13 circuit operation manual notpgm_en (pio1_3) flash rom write protect/ program enable (low) or program disable (high) slow_s/w (pio1_4) checking the connection of external features with vcr scart such as vcr and general power on/off status. Connect power on(high), not connect or power off(low) rs23...

  • Page 15

    14 circuit operation manual following is the memory map table. Emi bank 3 (flash) emi bank 2 emi bank 1 emi bank 0 shared sdram peripheral configuration registers reglon 3 reglon 2 reglon 1 reglon 0 0x70000000 0x7fffffff 0x60000000 0x50000000 0x40000000 0x20040000 0x00000000 0xc0000000 0x80000800 mi...

  • Page 16

    15 circuit operation manual memwait wait signal is produced in external device when accessing sram and peripheral devices. Wait signal is maintained as order status in the high status motivated by processor clock. Not_oe read strobe readnotwrite the ability to read or write of processing cycle. Acce...

  • Page 17

    16 circuit operation manual emi interface timing.

  • Page 18

    17 circuit operation manual 4. Front-end interface (1) tuner module tuner and qpsk demodulator are combined into one module. Following feature shows the block diagram. 2-wire bus control direct conversion zif t uner 4mhz 4mhz tda8260 inside lpf matched filter matched filter 2-wire bus control agc co...

  • Page 19

    18 circuit operation manual data parity no error uncorrectible packet no error byte clk p a c k e t str out e r r o r by t e d a t a parallel data output timing ts output is made by the serial or parallel function. The relationship between ts output data and control signal is showing in the followin...

  • Page 20

    19 circuit operation manual sta r t bi t clk p a c k e t d7 e r r o r first bit of the packet data parity parity useful data 1 packet rs0 = 0 rs0 = 1 serial data output timing serial output timing (2) related with lnb. 1) lnb power and 22khz tone pulse the power supplied to lnb sends the 22khz tone ...

  • Page 21

    20 circuit operation manual 2) loop through supports loop through for the interface function of other satellite devices. That means, in other satellite device, the control of lnb related voltage and tone are possible. If the signal of aux/ird control is in high status, the lnb voltage is provided fr...

  • Page 22

    21 circuit operation manual 3) color bar cvbs, y, c, signals ma v 32.88 1.233 28.88 1.000 12.01 1.80 4.00 8.00 0.450 0.300 0.150 0.068 ma v 28.88 1.000 17.07 5.27 0.640 13.07 0.490 21.03 0.791 0.196 ma v 26.68 1.000 9.00 0.800 0.00 0.000 white yellow cyan green magenta red blue block 400 388 316 284...

  • Page 23

    22 circuit operation manual 1-4) video output there are 2 video output port in the dsd-9255mp products. (tv scart, rca jack) the output of r,g and b signals are sent to tv scart through video buffer and lpf (low pass filter) originated from the sti5518 output. There are two control signals as of fas...

  • Page 24

    23 circuit operation manual chart 81. Scart pinspec. 1) pcm audio audio related output of the sti5518 is made in the form of pcm format and ac3 interface format. Dsd-9255m uses the serial data of pcm format. Pcm data output format is in standard format and i2s compatible pcm format. Followings are t...

  • Page 25

    24 circuit operation manual pcm timing analogue audio signals that are modified at audio dac are amplified by three times after going through low pass filter. The output is made after the amplification through av switch or buffer. 2) digital audio(spdif format) use pcm1754/texas instruments which ar...

  • Page 26

    25 circuit operation manual a. Initialize multi-purpose pio port b. Sti5518 chip version detection c. Set dmt default multi-purpose pio port d. Initialize the os20 software scheduler e. Initialize the interrupt subsystem f. Flash vendor check g. Booting mode check(uart debugging mode / factory test ...

  • Page 27

    26 circuit operation manual --- develop driver configuration --- [uartio fitted] [unhosted not fitted] [streport fitted] --- mpeg driver configuration --- [b_on_the_fly fitted] [enable_avsync fitted] [dont_blow_up_half_size_pictures not fitted] [built_for_16mbit fitted] [decode_elementary_stream not...

  • Page 28

    27 circuit operation manual 7) teletext driver & process start teletext driver library v1.0 - version of apr 04 2000 at 01:34:03 creating teletext vbi task (priority=9) the teletext_data_transfer task is running creating teletext stb page filter task (priority=9) the ttx_stb_page_filter task is runn...

  • Page 29: Fixing Errors

    28 fixing errors (1) no response of display boot signal. 1. Booting led error start no display led signal. Yes yes no no no no no no no no yes yes yes yes yes yes yes a power on? Is reset ic working? Modify power status. Check reset circuit. Check 27mhz crystal and other peripheral circuit. Oscillat...

  • Page 30

    29 fixing errors (1) locking error 2. Poor quality screen check the power status of tuner(30v, vcc_tuner,3v3) 30v, 3v3 voltage ok? Tr(q808)ok?(vcc_tuner) replace the smps replace q808. Lnbp input control? Lnbp output ok?(ic27 pin3) eliminate problem causing factors. Replace lnbp check the power of l...

  • Page 31

    30 fixing errors (2)disabled screen after locking yes yes no no no no yes yes no yes yes yes no check the 3.3v power of tuner(ripple, voltage) fix the problem check error pin.(whether the output is in high status.) replace tuner tuner interface signal check? (ts_data, f_packet_clk, f_strt, f_b_clk) ...

  • Page 32

    31 fixing errors (1) audio error 3. Errors in audio and video check the power status of audio dac eliminate problems check the input signal pcm data, sclk, lrclk, pcmclk) yes no yes no no check the sti 5518 check the interface of audio amp ic. Replace sti5518 replace audio dac eliminate problems rep...

  • Page 33

    32 fixing errors (2) video error led booting ok sti5518 cvbs out check pin34 video buffer, low pass filter check confirm and execute the fixing process confirm the connection status of tracking port and execute the fixing process check the power status of sit5518 video (pin 23, pin30) check related ...

  • Page 34

    Bom list ✐ caution : in this service manual, some parts can be changed for improving their performance without notice in the parts list. So, if you need the latest parts information, please refer to ppl(parts price list)in service information center(http://svc.Dwe.Co.Kr) 33 loc parts_code parts_name...

  • Page 35

    34 bom list loc parts_code parts_name parts_descr remark c314 hcbk104kba c chip cera 50v x7r 0.1mf k 1608 c359 hcbk104kba c chip cera 50v x7r 0.1mf k 1608 c360 hcbk104kba c chip cera 50v x7r 0.1mf k 1608 c361 hcbk104kba c chip cera 50v x7r 0.1mf k 1608 c362 hcbk104kba c chip cera 50v x7r 0.1mf k 160...

  • Page 36

    35 bom list loc parts_code parts_name parts_descr remark q912 t2sa1980sf tr chip 2sa1980sfg-cag q913 t2sa1980sf tr chip 2sa1980sfg-cag r101 hrfs101jba r chip 1/16 100 ohm j 1608 r102 hrfs101jba r chip 1/16 100 ohm j 1608 r103 hrfs560jba r chip 1/16 56 ohm j 1608 r104 hrfs101jba r chip 1/16 100 ohm j...

  • Page 37

    36 bom list loc parts_code parts_name parts_descr remark r308 hrfs103jba r chip 1/16 10k ohm j 1608 r309 hrfs682jba r chip 1/16 6.8k ohm j 1608 r310 hrfs682jba r chip 1/16 6.8k ohm j 1608 r311 hrfs682jba r chip 1/16 6.8k ohm j 1608 r312 hrfs682jba r chip 1/16 6.8k ohm j 1608 r313 hrfs223jba r chip 1...

  • Page 38

    Loc parts_code parts_name parts_descr remark c272 cexf1c470a c electro 16v rsm 47mf (5x7) tp c273 cexe1c101e c electro 16v rm 100mf 5x11 c351 cexf1c220a c electro 16v rsm 22mf (5x7) c352 cexf1c100a c electro 16v rsm 10mf 5x7 c353 cexf1c100a c electro 16v rsm 10mf 5x7 c354 cexf1c100a c electro 16v rs...

  • Page 39

    38 bom list loc parts_code parts_name parts_descr remark ic802 1ka431az ic regulator ka431az 1% to-92 l803 56c220k695 coil choke(cap type) 22uh k 9x11.1 (cap type) l804 56c220k695 coil choke(cap type) 22uh k 9x11.1 (cap type) l805 56c220k695 coil choke(cap type) 22uh k 9x11.1 (cap type) l806 56c220k...

  • Page 40: Schematic Diagram

    39 schematic diagram.

  • Page 41

    40 schematic diagram.

  • Page 42

    41 schematic diagram.

  • Page 43

    42 schematic diagram.

  • Page 44

    43 schematic diagram.

  • Page 45

    44 schematic diagram.

  • Page 46: Parts Placement(Arrangement)

    45 parts placement(arrangement).

  • Page 47

    46 parts placement(arrangement).

  • Page 48

    47 parts placement(arrangement) dsd-9255 front dsd-9256 front.

  • Page 49

    48 parts placement(arrangement).

  • Page 50

    686, ahyeon-dong mapo-gu seoul, korea c.P.O. Box 8003 seoul, korea daewoo electronics corp..