HD404449 Datasheet, PDF (80/123 Pages) Hitachi Semiconductor – HD404449 SERIES

HD404449 Series
Octal counter
(OC1, OC2)
SO₁ , SO₂
Idle control
logic
SCK₁ , SCK₂
I/O control
logic
Clock
SI₁ , SI ₂
1/2
1/2
Serial interrupt
request flag
(IFS1, IFS2)
Serial data
register (SR1L/U,
SR2L/U)
Transfer
control
Selector
System ^øPER
clock
Prescaler S (PSS)
3
Serial mode register
1A, 2A (SM1A,
SM2A)
Serial mode register
1B, 2B (SM1B,
SM2B)
Figure 66 Serial Interfaces 1 and 2 Block Diagram
Serial Interface Operation
Selecting and Changing the Operating Mode: Tables 28 (A) and 28 (B) list the serial interfaces’
operating modes. To select an operating mode, use one of these combinations of port mode register A
(PMRA: $004), serial mode register 1A (SM1A: $005), and serial mode register 2A (SM2A: $01B)
settings; to change the operating mode of serial interface 1, always initialize the serial interface internally
by writing data to serial mode register 1A; and to change the operating mode of serial interface 2, always
initialize the serial interface internally by writing data to serial mode register 2A. Note that serial interface
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