Toshiba A29019 Service Note
Publish Date: 99/05/26
M-FSA29019a(TF471-478).pdf
M-FSA29019a(TF610).pdf
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BSI No.: A29019
Subject:
Change the Service Manuals
Model: TF471, TF478, TF610
Category Field Application Unit
Modification/Correction of
Service Manual
Factory Application:
To be applied when necessary Operator's Manual/Service
CONTENT
1. Reason for Modification
To correct the information in the Service Manuals.
2. Details of Modification
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Manual
TF471/TF478
Refer to pages 7-8 to 7-15 attached.
TF610
Refer to pages 7-18 and 7-19 attached.
Attached Files
TF471/TF478
2.1 Facsimile Transmission Mode
2.1.1 Facsimile Memory Transmission Mode
7-02-01.eps
Fig. 7-2-1
(1) The CCD sensor mounted on the SCN PBA reads a document and converts it into analog data,
and then transfers the data to the DSC of the ENGINE (IC301).
(2) The DSC converts the analog data into digital 8-bit image data through the built-in A/D converter
and performs data correction processes such as background correction, ACC (Auto Contrast
Control), half-tone processing, and black and white (binary) processing. The HDMA of the MPU
transfers the corrected image data (digital/parallel) to the DRAM (IC307) in DMA mode.
(3) T o con vert the image data in the DRAM into the MMR compressed data which provides efficient
compression, the image data is transferred to the acceler ator of the TURBO by HDMA in DMA
mode.
(4) The image data is converted into the MMR compressed data by software processing and accu-
mulated in the SRAM (IC303).
(5) The MMR compressed data in the SRAM is transferred to the DRAM by software processing
and accumulated in the DRAM until the line is connected and the coding scheme of the destination is found out.
Chapter 7 7-8 SERVICE MANUAL
TF471/TF478
(6) When the coding scheme of the destination is found out, the MMR compressed data in the
SRAM is transferred to the SRAM by software processing so that it is converted to data which
corresponds with the coding scheme of the destination.
(7) The MMR compressed data in the SRAM is transferred to the accelerator by software process-
ing.
(8) The MMR compressed data is converted into image data by software processing and trans-
ferred to the DRAM by the HDMA.
(9) The image data in the DRAM is transferred to the accelerator by the HDMA in DMA mode.
(10) The image data is converted into the data which corresponds with the coding scheme (MMR,
MH, or MR) of the destination and accumulated in the SRAM (IC303).
(11) The µDMA transfers the compressed data (MMR, MH or MR) transferred in DMA mode to the
modem in DMA mode.
(12) The modem modulates the compressed data (MMR, MH or MR) transferred in DMA mode into
analog data for telephone lines and transfers it to the AFE (IC324).
(13) The transferred analog data (for telephone lines) is transferred to the NCU PBA through the
equalizer and attenuator of the AFE and then sent to the telephone line.
SERVICE MANUAL 7-9 Chapter 7
TF471/TF478
2.1.2 Facsimile Direct Transmission Mode
7-02-02.eps
Fig. 7-2-2
(1) The CCD sensor mounted on the SCN PBA reads a document and converts it into analog data,
and then transfers the data to the DSC of the ENGINE (IC301).
(2) The DSC converts the analog data into digital 8-bit image data through the built-in A/D converter
and performs data correction processes such as background correction, ACC (Auto Contrast
Control), half-tone processing, and black and white (binary) processing. The HDMA of the MPU
transfers the corrected image data (digital/parallel) to the DRAM (IC307) in DMA mode.
(3) The image data is then transferred to the accelerator by the HDMA in DMA mode.
(4) The image data is converted into the data which corresponds with the coding scheme (MMR,
MH, or MR) of the destination and accumulated in the SRAM (IC303).
(5) The compressed data in the SRAM is transferred to the MODEM by µDMA in DMA mode.
(6) The modem modulates the compressed data (MMR, MH or MR) transferred in DMA mode into
analog data for telephone lines and transfers it to the AFE (IC324).
(7) The transferred analog data (for telephone lines) is transferred to the NCU PBA through the
equalizer and attenuator of the AFE.
The transferred analog data (for telephone lines) is sent to the telephone line through the NCU
PBA.
Chapter 7 7-10 SERVICE MANUAL
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