Rohm LAPIS SEMICONDUCTOR ML620Q503, User Manual

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ML620Q503/Q504 User's Manual
Chapter 11 Synchronous Serial Port (SSIO)
FEUL620Q504 11–11
11.3.3 Transmit/Receive Operation
When “1” is written to the S0MD1 bit and “1” is written to the S0MD0 bit of the serial mode register (SIO0MOD), this
LSI is set to a transmit/receive mode.
When the S0EN bit of the serial port control register (SIO0CON) is set to “1”, transmission/reception starts. When
transmission/reception of 8/16-bit data terminates, a synchronous serial port interrupt (SIO0INT) occurs and the S0EN
bit is set to “0”.
Receive data is input from the SIN0 pin, and transmit data is output from the SOUT0 pin.
When an internal clock is selected in the serial port mode register (SIO0MD), the LSI is set to a master mode and when
an external clock (SCK0) is selected, the LSI is set to a slave mode.
The serial port mode register (SIO0MOD) enables selection of MSB first or LSB first.
The receive data input pin (SIN0), the transmit data output pin (SOUT0), and transfer clock input/output pin (SCK0)
must be set to the tertiary function.
Figure 11-10 shows the transmit/receive operation waveforms of the synchronous serial port (16-bit length, LSB first,
clock types 0 and positive-logic).
Figure 11-10 Transmit/Receive Operation Waveforms of Synchronous Serial Port
(16-bit Length, LSB first, Clock Type 0 and positive-logic)
11.3.4 Pin Settings
To enable the SSIO function, the applicable bit of each related port register needs to be set. See Chapter 17, “Port 0”,
Chapter 20, “Port 3”, Chapter 21, “Port 4”, and Chapter 22, “Port 5” for details about the port registers.
For SIN0, SCK0 and SOUT0, the ports can be selected from several possibilities.
Be sure to select one of the following combinations of ports for SIN0/SCK0/SOUT0.
SSIO pin Combination 1 Combination 2 Combination 3 Combination 4
SSIO SIN0,SCK0,
SOUT0
P01,P02,
P00
P31,P32,
P30
P41,P42,
P40
P51,P52,
P50
Note that only one port can be selected as port.
If using P02 as SCK0 in master mode, SCK0 Max clock output frequency is 2MHz.
15
S0EN
0 1 2 3 12 13 15 14
Receive data
SCK0
SIN0
Shift register
SIO0INT
0 1 2 3 13 14
SIO0RCH, L
15
SOUT0
0 1 2 3 12 13 14
Transmit data
SIO0TRH,L
12