HD6433937 Datasheet, PDF (262/521 Pages) Hitachi Semiconductor – Hardware Manual

Bit 7: SCI1 module standby mode control (S1CKSTP)
Bit 7 controls setting and clearing of module standby mode for SCI1.
Bit 7
S1CKSTP Description
0
SCI1 is set to module standby mode*¹
1
SCI1 module standby mode is cleared
(initial value)
Note: * Setting to module standby mode resets SCR1, SCSR1, SDRU and SDRL.
10.2.3 Operation
Either 8-bit or 16-bit transfer data can be selected as the transfer format. Eight internal clocks can
be selected as the clock source.
1. Clock
The serial clock can be selected from 8 internal clocks. When an internal clock is selected, the
SCK₁ functions as the clock output. When continuous clock output mode is set (SNC1, SNC0 = 10
in SCR1), the clock selected by bits CKS2 to CKS0 (ø/1024 to ø_W/4) is output continuously from
the SCK₁.
2. Data transfer format
The SCI1 transfer format is shown in figure 10-2. LSB-first transfer is used (i.e. transmission and
reception are performed starting with the least significant bit of the transfer data). Transfer data is
output from one falling edge of the serial clock until the next falling edge. Receive data is latched
at the rising edge of the serial clock.
SCK₁
SO₁/SI₁
Bit 0 Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7
Figure 10-2 Transfer Format
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