RL78/G14, RL78/G1C, RL78/L12, RL78/L13, RL78/L1C Group Clock Synchronous Single Master Control Software Using CSI Mode of Serial Array Unit

RL78/G14, RL78/G1C, RL78/L12, RL78/L13, RL78/L1C Group

Clock Synchronous Single Master Control Software Using CSI Mode of Serial Array Unit

1. Specifications

This software program uses the 3-wire serial I/O communications (CSI mode) of the serial array unit (SAU) of the

RL78 Family microcontroller to control clock synchronous communication. The SPI mode single master can be controlled by adding control of SPI slave device selection through port control.

Table 1-1 summarizes the peripheral devices to be used and their uses. Figure 1.1 illustrates a sample configuration.

The major functions are summarized below.



This software is a block-type device driver that uses the 3-wire serial I/O communications (CSI mode) of the SAU of the RL78 Family microcontroller as the master device in clock synchronous single master communication.



The MCU’s internal clock synchronous (3-wire) serial communication function is used. It can only be used with a single user-configured channel; that is, it cannot be used with multiple channels.



The sample code does not support chip-select control. To control the SPI device, the chip-select control must be separately embedded.



This software supports MSB-first transfer.



The software supports transfer by the CPU but not by the DMAC.



It does not support using an interrupt to start the transfer.

Table 1-1 Peripheral Devices Used and their Uses

Peripheral Device

SAU

Port

Use

Clock synchronous (3-wire method) serial

1 channel (required)

For SPI slave device select control signals. As many ports as there are SPI slave devices in use are necessary (required).

Not used by this sample code.

RL78

Port

SAU

Slave device select control signal

Clock synchronous

(3-wire method) serial

Slave Device

Figure 1.1 Sample Configuration

R01AN1195EJ0105 Rev.1.05

Mar 31, 2016

Page 4 of 54