Kyocera Mita FS-6750, Service Manual

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Operation theory
Logic controller system
4-38 FS-6750
Signals used for the engine interface
The following signals are used for the engine interface communication. Figure on
next page shows a simplified function diagram of the engine interface and the sig-
nals.
Table 4. 11 Engine interface signals
Signal Meaning Active Definition
SBSYN Status-
BuSY-sigNal Low Determines which direction for the engine system to
transfer the status data. If SBSYN is true, the control-
ler is unable to transfer the command data towards the
engine system. The controller can read in the status
data transferred from the engine system by forwading
SCLK to the engine.
SDIR Serial line
DIRection Low The engine system informs the controller of the direc-
tion of serial communication. If SDIR is high, the con-
troller can transmit command data to the engine
system, and if low, the engine system can transmit sta-
tus data to the controller.
SCLK Serial CLocK - This signal is a clock for synchronization of status data
and command data transmitted between the engine
system and the controller and is output from the con-
troller. The controller reads status data at the leading
edge of SCLK and also outputs command data in syn-
chronization with the trailing edge. Eight pulses of
SCLK are output in a cycle of communication.
SI Serial Input
data - This signal is 8-bit command data output from the con-
troller to the engine system and is output in synchroni-
zation with the trailing edge of SCLK. This signal is
enabled only if SDIR is low and SBSYN is high.
SO Serial Out-
put data - This signal is 8-bit status data output from the engine
system to the controller and is output in synchroniza-
tion with the trailing edge of SCLK. This signal is
enabled only if SDIR is high and SBSYN is low.
ENGIR ENGine
Interrupt
Request High When the status of the engine system changes and the
controller must be immediately informed of the
change, this signal will become low for certain period
and then return to the high level.