Toshiba ESTUDIO170F, Руководство по обслуживанию

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e-STUDIO170F Circuit Description January 2005 © TOSHIBA TEC
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(1) The CIS detects the LED’s light reflected by a document as an analog electric signal and sends it
to the DSC (IC27).
(2) The DSC converts the electric signal to a digital signal and subjects it to data correction, then
converts it to raster data. The raster data is serially transferred to the DSC interface of the ASIC
(IC15).
(3) The raster data is converted from serial to parallel data by the DSC interface and transferred to
the PIX area of the SDRAM (PIX-SDRAM: IC1) through the SDRAM controller of the ASIC. Dur-
ing this period, the system communicates with the destination to identify the coding for the data
to be transmitted.
For memory transmission, go to step (4).
For direct transmission, go to step (6).
(4) The raster data is transferred to the CODEC (IC16) through the CODEC interface of the ASIC
where it is coded to data in the JBIG format. Then the JBIG coded data is transferred to the SYS
area of the SDRAM (SYS-SDRAM: IC1) through the SDRAM controller. This allows the coded
data for the documents for transmission to be stored in the SYS-SDRAM.
(5) The JBIG coded data is transferred to the CODEC where it is decoded to raster data. Then the
raster data is transferred to the PIX-SDRAM.
(6) The raster data is transferred to the CODEC where it is coded in accord with the coding format
(MH, MR, MMR or JBIG) specified by the destination. Then the coded data is transferred to the
SYS-SDRAM. This allows one page of coded data to be stored in the SYS-SDRAM.
(7) The coded data is transferred to the MODEM (IC53) through the MODEM interface of the ASIC
where it is modulated to an analog signal for telephone lines. Then the modulated analog signal
is sent to the telephone line through the NCU PBA.