MITSUBISHI MICROCOMPUTERS
M37274EFSP
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER
and ON-SCREEN DISPLAY CONTROLLER
For the main data slice line, the count value of pulses in the window
For the main data slice line, reference clock is counted in the period
from a falling of the clock pulse set in bits 0 to 2 of clock run-in detect
register 2 (address 00E916) to the next falling. The count value is
stored in bits 3 to 7 of clock run-in detect register 1 (address 00E816)
(When the count value exceeds “1F16,” “1F16” is held). For the sub-
data slice line, the count value is stored in bits 3 to 7 of clock run-in
detect register 3 (address 020816). Read out these bits after the
occurence of a data slicer interrupt (refer to (11) Interrupt Request
Generating Circuit).
is stored in clock run-in register 1 (address 00E616; refer to Figure
44). For the sub-data slice line, the count value of pulses in the window
is stored in clock run-in register (address 020916; refer to Figure 45).
When this count value is 4 to 6, it is determined as a clock run-in.
Accordingly, set the count value so that the window may start after
the first pulse of the clock run-in (refer to Figure 46).
The contents to be set in the window register are written at a falling
of the horizontal synchronous signal. For this reason, even if an
instruction for setting is executed, the contents of the register cannot
be rewritten until a falling of the horizontal synchronous signal.
Figure 48 shows the structure of clock run-in detect registers 1 and
3.
Clock Run-in Register 1
b7 b6 b5 b4 b3 b2 b1 b0
0
1
0
1
Clock run-in register 1 (CR1) [Address 00E616
]
R
R
W
W
B
Name
Functions
After reset
0
0
to
3
Clock run-in count value
of main-data slice line
(CR10 to CR13)
4, 6
0
0
R
R
W
W
Fix these bits to “1.”
5, 7
Fix these bits to “0.”
Fig. 44. Clock Run-in Register 1
48
RENESAS [ RENESAS TECHNOLOGY CORP ]
