Renesas M32R/ECU Series

12
12-33
Serial I/O
12.4 Receive Operation in CSIO Mode
32180 Group User's Manual (Rev.1.0)
Figure 12.4.1 Procedure for Initializing CSIO Reception
Initialize CSIO reception
Note 1: Necessary when the internal clock is selected.
Note 2: If the internal clock and a divide-by ratio = 1 are selected, caution must be used when setting the baud rate
register so that the transfer rate will not exceed 2 Mbps.
•
Set the register to CSIO mode
•
Select the internal or external clock
Set SIO Transmit/Receive Mode Register
(When using the DMAC)
Set DMAC
(When using interrupts)
Set Interrupt Controller
•
Select the source of receive interrupt request
Set SIO interrupt related registers
•
Divide-by ratio = H'00 to H'FF
(Note 2)
Set SIO Baud Rate Register
•
Select the clock divider divide-by ratio
(Note 1)
Set SIO Transmit Control Register
Set Input/Output Port
Operation Mode Register
Serial I/O
related registers
Set SIO Receive Control Register
•
Set the receive enable bit
End of CSIO receive initialization
•
Enable or disable receive interrupt requests
(8) Selecting pin functions
Because the serial I/O related pins serve dual purposes, set the pin functions for use as SIO pins or input/
output ports. (See Chapter 8, “Input/Output Ports and Pin Functions.”)