Renesas RL78/G13 Installation and operating instructions

APPLICATION NOTE
R01AN6883EJ0100 Rev.1.00 Page 1 of 38
June.15.23
RL78/G13
Handshake-based SPI Master Transmission/Reception
Introduction
This application note describes how the serial array unit (SAU) performs master transmission/reception by
the simple SPI (CSI). The SAU uses the chip select (CS) signal to select a slave device and perform single
transmission/reception. The SAU also performs handshake processing using the BUSY signal.
Target Device
RL78/G13
When applying the sample program covered in this application note to another microcomputer, modify the
program according to the specifications for the target microcomputer and conduct an extensive evaluation of
the modified program.

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Contents
1. Specifications ..........................................................................................................................4
1.1 Outline of CSI Communication ................................................................................................................ 4
1.2 Outline of Communication ....................................................................................................................... 5
1.3 Communication Format ........................................................................................................................... 7
1.4 Handshake .............................................................................................................................................. 7
1.5 Specification Details ................................................................................................................................ 8
2. Operation Confirmation Conditions ........................................................................................11
3. Related Application Notes......................................................................................................11
4. Hardware Descriptions ..........................................................................................................12
4.1 Example of Hardware Configuration ..................................................................................................... 12
4.2 List of Pins to be Used .......................................................................................................................... 13
5. Description of the Software....................................................................................................14
5.1 List of Option Byte Settings ................................................................................................................... 14
5.2 List of Constants.................................................................................................................................... 14
5.3 List of Variables ..................................................................................................................................... 15
5.4 List of Functions .................................................................................................................................... 16
5.5 Function Specifications ......................................................................................................................... 16
5.6 Flowcharts ............................................................................................................................................. 22
5.6.1 Initialization process ............................................................................................................................ 22
5.6.2 Reset source reading .......................................................................................................................... 22
5.6.3 CPU clock Configuration ..................................................................................................................... 23
5.6.4 Port Configuration ............................................................................................................................... 23
5.6.5 SAU Configuration............................................................................................................................... 24
5.6.6 CSI00 Configuration ............................................................................................................................ 25
5.6.7 TAU0 Configuration............................................................................................................................. 26
5.6.8 Flowchart of Main Processing ............................................................................................................. 27
5.6.9 User Main Initialization ........................................................................................................................ 28
5.6.10 TAU0 channel 3 upper 8 bits start operation....................................................................................... 29
5.6.11 CSI00 start operation .......................................................................................................................... 29
5.6.12 CSI00 Transmit/Receive Processing .................................................................................................. 30
5.6.13 INICSI00 interrupt processing ............................................................................................................. 31
5.6.14 Flowchart of CSI Status Check ........................................................................................................... 32
5.6.15 Flowchart of CSI Transmission/Reception .......................................................................................... 33
5.6.16 Flowchart of CSI Transmission ........................................................................................................... 34
5.6.17 Flowchart of CSI Reception................................................................................................................. 35
5.6.18 Flowchart of Wait for Slave Response ................................................................................................ 36
6. Sample Code.........................................................................................................................37
7. Reference Documents ...........................................................................................................37

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1. Specifications
The serial array unit (SAU) described in this application note performs CSI master transmission/reception.
The chip select (CS) signal uses the port.CS Handshake processing using the BUSY signal is also performed
for the slave device selected by the CS signal.
1.1 Outline of CSI Communication
CSI communication is clock-synchronous serial communication using three signal lines, namely, serial
clock (SCK), serial data input (SI), and serial data output (SO). SPI (Serial Peripheral Interface) uses an
additional chip select (CS) signal to select the slave device. The relationship among these signals is shown in
Figure 1-1.
Figure 1-1 Outline of CSI Communication
RL78/G13 RL78/G13
Master Slave 1
SCK
SO
SI
BUSY
RL78/G13
Slave 2
CS
Serial clock (output)
Serial data (output)
Serial data (input)
SCK
SI
SO
BUSY
CS
SCK
SI
SO
BUSY
CS
Simple SPI (CSI) signals
Additional signal for SPI
BUSY signals
SCK signal :Serial clock signal. Output by the master.
SO signal : Serial data output signal Connected to the SI signal pin of the target device.
SI signal : Serial data input signal. Connected to the SO signal pin of the target device.
CS signal : Used by the master device to select the target slave device.
BUSY signal : Handshake signal used in this application note.
Slave select signal (output)
The master first selects the slave with which it wants to communicate with the CS signal. Then, the master
outputs data to the SCK signal line and the SO signal line in synchronization with the SCK signal, and inputs
data from the SI signal line.
In SPI/CSI communication, the slave needs to become ready for communication by the time the master
starts communication (sending the SCK signals). In this application note, the BUSY signal is used to confirm
that the slave is ready for communication. The master detects a low-level BUSY signal and then initiates a
communication session.

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1.2 Outline of Communication
In this application note, a command and communication for the command are performed at intervals of
1 ms. A set of a command and communication for the command is defined as a slot. Figure 1-2 shows an
outline of slot processing and Table 1-1 lists the commands to be used.
Figure 1-2 Outline of Slots
Table 1-1 Commands to be Used
Command
Outline of Operation
Status check
Checks the number of data characters that the slave can transmit
or receive.
Receive
Receives data from the slave.
Transmit
Transmits data to the slave.
Transmit/receive
Transmits and receives data to and from the slave.
Table 1-2 lists the peripheral functions and their uses. Figure 1-3 and Figure 1-4 show the CSI
communication operations.
Table 1-2 Peripheral Functions and Their Uses
Peripheral Function
Use
Serial array unit 0
Performs CSI master communication using the SCK00 signal (clock
output), SI00 signal (receive data), and SO00 signal (transmit data).
Port
Uses P52 for CS1 signal, P53 for CS2 signal, and P54 for BUSY
signal.
Timer array unit 0
Channel 3
The upper 8 bits are used as a 1-ms interval timer.
The lower 8 bits are used as a 16-µs interval timer.
Slot #1
Slot #2
Slot #3
1 ms
1 ms
1 ms
Slot
Command Communication
for the command
Blank

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Figure 1-3 Timing chart for status check commands
SI00
SCK00
SO00
INTCSI00
CS1 / CS2
BUSY
Slave Selection
00H: Status Confirmation
48H
Status transmission
from the slave
Send/receive
completed
08H
Master-side operation
Slave-side operation
FFH: Dummy FFH: Dummy
Send/receive
completed
Send/receive
completed
Figure 1-4 Timing chart of commands sent and received
SI00
SCK00
SO00
INTCSI00
CS1 / CS2
BUSY
Slave Selection
Send/receive
commands
Status transmission
from the slave
Send/receive
completed
Master-side operation
Slave-side operation
Send/receive
completed
Send/receive
completed
1st received data
Final received data
Final transmission data
1st transmission data

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1.3 Communication Format
Table 1-3 lists the characteristics of the CSI communication format that is used in the sample code.
Table 1-3 Communication Format
Item Specification Remarks
Communication speed
1 Mbps
About 200 kbps at minimum
Data bit length
8 bits/character
Transfer order
MSB first
Communication type
Type 1
Communication mode
Single transfer
Communication
direction
Receive/transmit/transmit and
receive
Maximum number of
characters transferred
63 characters/slot 32 characters by default
1.4 Handshake
In this application note, handshaking using the BUSY signal is performed to secure the setup time required
for the communication operation on the slave side. A timeout of 16 µs is set up in case no response using
the BUSY signal is returned from the slave. If no response is returned from the slave within this period, the
master assumes that the slave cannot establish a communication (or does not exist) and terminates
communication processing.
Figure 1-5 shows an example of handshaking for status checking. The master measures the time from the
falling edge of the CS signal until the BUSY signal goes low. When detecting that the BUSY signal goes low
without the timeout, the master sends the command. After confirming that command transmission is
completed through the transfer completion interrupt, the master measures the time until the BUSY signal
goes low again. In this way, the master synchronizes with the slave by checking the BUSY signal each time
communication starts.
However, if the slave supports continuous reception or can secure enough time to prepare communication
data, synchronization using the BUSY signal is not necessary.
Figure 1-5 Handshaking Example
SCK
TSFmn
INTCSIp
CS1 / CS2
BUSY
Selection of slave
Command transmission
End of transmission End of reception
Status reception Status reception
Time measurement
to detect timeout
End of reception
Generally, the BUSY signal is not required for SPI communication-dedicated slave devices such as
EEPROM because they are always ready for communication. When connecting such SPI communication-
dedicated slave devices, pull down the BUSY signal input pin. Additionally, the timeout processing can be
removed by deleting the wait() function from the program. In such a case, perform communication according
to the commands that are defined for the SPI communication-dedicated slave devices and their
communication protocol.

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1.5 Specification Details
After completion of initialization, this sample code selects a slave, checks that slave’s status, and then
transmits and receives data, switches slaves, and repeats the same operation.
(1) Initialize the port.
<Conditions for setting the port>
Use P52 controlling the CS1 signal as an output port to output a high-level signal.
Use P53 controlling the CS2 signal as an output port to output a high-level signal.
Use P54 detecting the BUSY signal as an input port.
(2) Initialize the timer.
<Conditions for setting the timer>
Run Channel 3 as two 8-bit interval timers.
Set the operating clock frequency to 125 kHz (derived by dividing fCLK by 256).
Use the upper TM03H as a 1-ms interval timer.
Use the lower TM03 as a 16-µs interval timer.
Set the priority of the interrupts (INTTM03H, INTTM03) to the lowest level (3, by default).
(3) Initialize the CSI.
<Conditions for setting the CSI>
Use SAU0 channel 0 as CSI00.
Use CK00 as the transfer clock.
Assign the clock output to the P10/SCK00 pin, the data input to the P11/SI00 pin, and the data output
to the P12/SO00 pin.
Use single transfer mode as the transfer mode.
Set the data length to 8 bits.
Set the phase between the data and clock to type 1.
Set the order of data transfer mode to MSB first.
Set the transfer rate to 1 Mbps.
Use transmission end and reception end interrupts as the interrupt (INTCSI00).
Set the priority of the interrupt (INTCSI00) to the lowest level (3, by default).

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(4) After initialization is completed, the master performs communication with the slave as shown in the
following steps.
①The master waits in HALT mode for a 1-ms interval timer interrupt (INTTM03H).
②When the master is released from HALT mode by an INTTM03 interrupt, it issues the CS signal to
select the slave that is specified in the g_slave_select_flag flag, and then waits for a response from
the slave.
③When the BUSY signal goes low, the master proceeds to step 4. When a timeout is detected, the
master deselects the slave and proceeds to step 9.
④The master transmits a status check command and receives the slave status. When a timeout is
detected, or the slave status cannot be received, the master deselects the slave and proceeds to step
9. When the slave status is received, the master deselects the CS signal.
⑤The master again waits in HALT mode for a 1-ms interval timer interrupt (INTTM03H).
⑥When the master is released from HALT mode by an INTTM03 interrupt again, it issues the CS signal
to select the slave that is specified in the g_slave_select_flag flag, and then waits for a response from
the slave.
⑦When the master detects that the BUSY signal goes low, it proceeds to step 8. When a timeout is
detected, the master deselects the slave and proceeds to step 9.
⑧The master transmits and receives the number of data characters according to the status checked in
step 4. When a timeout is detected, the master deselects the slave.
⑨The master changes the g_slave_select_flag flag to switch the target slave. These steps are
subsequently repeated from step 1.
(5) Commands
Each communication operation begins with the transmission of a 1-byte command. Table 1-4 lists the
command formats. The master transmits a status check command and receives the response from the slave
in the first slot of a communication sequence. The master Confirm that the number of data characters that
the target slave can transmit or receive is equal to or greater than the specified number of data characters to
be transmitted or received. Then, the master transmits/receives data for the specified number of data
characters to/from the slave.
Table 1-4 Command Formats
Command Code
Command Outline
Status check
00000000B
Checks the number of data characters that the slave can
transmit or receive. The following responses can be made by
the slave:
01xxxxxxB: The number of characters that the slave can
transmit is xxxxxxB.
00xxxxxxB: The number of characters that the slave can
receive is xxxxxxB.
Reception
01xxxxxxB
The master receives xxxxxxB bytes of data.
Transmission
10xxxxxxB
The master transmits xxxxxxB bytes of data.
Transmission/reception
11xxxxxxB
The master transmits and receives xxxxxxB bytes of data.

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(6) Switching communication commands
Receive, transmit, and transmit/receive commands can be switched by changing the comment-out lines in
the r_main.c file. The transmit/receive command is set by default.

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2. Operation Confirmation Conditions
The operation of the sample code provided with this application note has been tested under the following
conditions.
Figure 2-1 Operation Confirmation Conditions
Item
Description
MCU used
RL78/G13 (R5F100LE)
Operating frequency

High-speed on-chip oscillator clock (fIH): 32 MHz
CPU/peripheral hardware clock: 32 MHz
Operating voltage
During VDD operation: 5.0 V
（
2.7V
～
5.5V
）
LVD detection voltage: Reset mode.
At rising edge TYP. 1.88V (1.84 V ～1.91 V)
At falling edge TYP. 1.84V (1.80 V
～
1.87 V)
Integrated development
environment (CS+)
CS+ V8.09.00 from Renesas Electronics Corp.
C compiler (CS+)
CC-RL V1.12.00 from Renesas Electronics Corp
Integrated development
environment (e2studio)
e2 studio Version: 2023-01 (23.1.0) from Renesas Electronics Corp.
C compiler (e2studio)
CC-RL V1.12.00 from Renesas Electronics Corp.
Integrated development
environment (IAR)
IAR Embedded Workbench for Renesas RL78 V4.21.2 from IAR
Systems Corp.
C compiler (IAR)
IAR C/C++ Compiler for Renesas RL78 V4.21.2.2420 from IAR Systems
Corp.
Board used
RL78/G13 (R5F100LE) Target Board
（
QB-R5F100LE-TB
）
3. Related Application Notes
See also the following application notes, which are related to this application note:
RL78/G13 Handshake-based SPI Slave Transmission/Reception (R01AN6884E) APPLICATION NOTE

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4. Hardware Descriptions
4.1 Example of Hardware Configuration
Figure 4-1shows an example of the hardware configuration used in the application note.
Figure 4-1 Hardware Configuration
RESET
P40/TOOL0
V
DD
OCD
RL78/G13
V
DD
/EV
DD
REGC
V
SS
/EV
SS
V
DD
P10/SCK00
P54
P11/SO00
P12/SI00
BUSY
P53
P52
CS1
CS2
RESET
V
DD
RL78/G13
V
DD
/EV
DD
REGC
V
SS
/EV
SS
P00
P137/INTP0
P10/SCK00
P11/SO00
P12/SI00
Master Slave1
RESET
V
DD
RL78/G13
V
DD
/EV
DD
REGC
V
SS
/EV
SS
P00
P137/INTP0
P10/SCK00
P11/SO00
P12/SI00
Slave2
Note 1. This schematic circuit diagram is simplified to show the outline of connections. When creating
circuits, design them so that they meet electrical characteristics by properly performing pin
processing. (Connect input-only ports to VDD or VSS individually through a resistor.)
Note 2. Connect pins (with a name beginning with EVSS), if any, to VSS, and connect pins (with a name
beginning with EVDD), if any, to VDD.

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4.2 List of Pins to be Used
Table 4-1 lists the pins to be used and their functions
Table 4-1 Pins to be Used and Their Functions
Pin Name
I/O
Description
P10/SCK00/SCL00/(TI07)/(TO07)
Output
Serial clock output pin
P11/SI00/RxD0/ TOOLRxD/SDA00/ (TI06)/(TO06)
Input
Data reception pin
P12/SO00/TxD0/ TOOLTxD/(INTP5)/(TI05)/(TO05)
Output
Data transmission pin
P54
Input
BUSY signal input from slaves
P53/(INTP11)
Output
Slave 2 select signal
P52/(INTP10)
Output
Slave 1 select signal
Caution In this application note, only the used pins are processed. When actually designing your circuit,
make sure the design includes sufficient pin processing and meets electrical characteristic
requirements.

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5. Description of the Software
5.1 List of Option Byte Settings
Table 5-1 summarizes the settings of the option bytes.
Table 5-1 Option Byte Settings
5.2 List of Constants
Table 5-2 lists the constants that are used in the sample code.
Table 5-2 Constants Used in the Sample Code
Constant
Name
Definition
location
Setting Value
Description
CS1_pin
r_cg_userdefine.h
P5_bit.no2
Port register to control the
CS1
signal
CS2_pin
r_cg_userdefine.h
P5_bit.no3
Port register to control the
CS2
signal
BUSYIN
r_cg_userdefine.h
P5_bit.no4
Port register to detect the BUSY signal
TX_NUM
r_main.c
32
Number of data characters to be transmitted
RX_NUM
r_main.c
32
Number of data characters to be received
TX_RX_NUM
r_main.c
32
Number of data characters to be
transmitted/received
data_length
r_main.c
1
Data length
MODE[]
r_main.c
*1
Command format
TX_DATA[]
r_main.c
*2
Stores 63 characters of transmit data, the
maximum number of characters transferred.
Notes: 1. For details, see Table 1-4.
2. In this application note, ASCII codes from 0x20 to 0x5F are stored.
Address
Setting Value
Description
000C0H
1110 1111B (EFH)
Stops the watchdog timer operation.
(Stops counting after the release of the reset state.)
000C1H
0011 1111B (3FH)
LVD reset mode
Detection Voltage:
On the rising edge: TYP. 1.88 V
On the falling edge: TYP. 1.84 V
000C2H
11101000B (E8H)
HS mode, HOCO: 32 MHz
000C3H
10000101B (85H)
Enables the on-chip debugging function.

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5.3 List of Variables
Table 5-3 lists the global variables that are used in this sample code.
Table 5-3 Global Variables Used in the Sample Code
Type
Variable Name
Contents
Function Used
uint8_t
g_tx_data
Buffer for transmit data
r_main.c
uint8_t
g_rx_data
Buffer for receive data
r_main.c
uint8_t
g_slave_select_flag
Slave select flag
r_main.c
uint8_t
g_status_confirmation_flag
Status check flag
r_main.c
uint8_t
g_timeout_flag
Timeout flag
r_main.c
uint8_t g_num Number of data characters that
the slave can transmit
r_main.c
uint8_t
g_rx_data_stored[]
Stores receive data.
r_main.c

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5.4 List of Functions
Table 5-4 lists the functions that are used in the sample code.
Table 5-4 Functions
Function Name
Outline
Source file
R_Systeminit
Initialization process
r_systeminit.c
R_CGC_Get_ResetSource
Reset source reading
r_cg_cgc_user.c
R_CGC_Create
CPU clock Configuration
r_cg_cgc.c
R_PORT_Create
Port Configuration
r_cg_port.c
R_SAU0_Create
SAU Configuration
r_cg_serial.c
R_CSI00_Create
CSI00 Configuration
r_cg_serial.c
R_TAU0_Create
TAU0 Configuration
r_cg_timer.c
main
Main processing
r_main.c
R_MAIN_UserInit
User Main Initialization
r_main.c
R_TAU0_Channel3_Higher8bits_Start
TAU0 channel 3 upper 8 bits start operating
r_cg_timer.c
R_CSI00_Start
CSI00 start operating
r_cg_serial.c
CSI00_Status_check
CSI status check
r_main.c
CSI00_Send_Receive
CSI transmission/reception
r_main.c
CSI00_Send
CSI transmission
r_main.c
CSI00_Receive
CSI reception
r_main.c
R_CSI00_Send_Receive
CSI00 Transmit/Receive Processing
r_cg_serial.c
r_csi00_interrupt
INICSI00 interrupt processing
r_cg_serial_user.c
wait
Wait for slave response
r_main.c
5.5 Function Specifications
This section describes the specifications for the functions that are used in the sample code.
[Function Name] R_Systeminit
Synopsis
Initialization process
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_port.h
r_cg_serial.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void R_Systeminit (void)
Explanation
Initialize each peripheral function.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] R_CGC_Get_ResetSource
Synopsis
Reset source reading
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_userdefine.h
Declaration
void R_CGC_Get_ResetSource(void)
Explanation
Reads the reset source.
Arguments
•None
Return value
•None
Remarks
None

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[Function Name] R_CGC_Create
Synopsis
CPU clock Configuration
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_userdefine.h
Declaration
void R_CGC_Create (void)
Explanation
Set the CPU clock.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] R_PORT_Create
Synopsis
Port Configuration
Header
r_cg_macrodriver.h
r_cg_port.h
r_cg_userdefine.h
Declaration
void R_CGC_Create (void)
Explanation
Configure the port settings.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] R_SAU0_Create
Synopsis
SAU Configuration
Header
r_cg_macrodriver.h
r_cg_serial.h
r_cg_userdefine.h
Declaration
void R_SAU_Create (void)
Explanation
Configure SAU settings.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] R_CSI00_Create
Synopsis
CSI00 Configuration
Header
r_cg_macrodriver.h
r_cg_serial.h
r_cg_userdefine.h
Declaration
void R_CSI00_Create (void)
Explanation
Configure CSI00 settings.
Arguments
•None
Return value
•None
Remarks
None

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[Function Name] R_TAU0_Create
Synopsis
TAU0 Configuration
Header
r_cg_macrodriver.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void R_CSI00_Create (void)
Explanation
Configure TAU0 settings.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] main
Synopsis
Main processing
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_port.h
r_cg_serial.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void main(void)
Explanation
Starts the operation of CSI00 and TAU03H.
Selects a slave.
Switches the slave select flag, g_slave_select_flag.
When slave 1 is selected: g_slave_select_flag = 0
When slave 2 is selected: g_slave_select_flag = 1
Sets the status check flag, g_status_confirmation_flag, to 0 (initial value) after
detection of a timeout or completion of transmission/reception.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] R_MAIN_UserInit
Synopsis
User Main Initialization
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_port.h
r_cg_serial.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void R_MAIN_UserInit(void)
Explanation
Main user initial settings.
Arguments
•None
Return value
•None
Remarks
None

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[Function Name] R_TAU0_Channel3_Higher8bits_Start
Synopsis
TAU0 channel 3 upper 8 bits start operating
Header
r_cg_macrodriver.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void R_TAU0_Channel3_Higher8bits_Start (void)
Explanation
Starts operation of the upper 8 bits of TAU0 channel 3.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] R_CSI00_Start
Synopsis
CSI00 start operating
Header
r_cg_macrodriver.h
r_cg_serial.h
r_cg_userdefine.h
Declaration
void R_CSI00_Start (void)
Explanation
Starts the operation of CSI00.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] CSI00_Status_check
Synopsis
CSI status check
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_port.h
r_cg_serial.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void CSI00_Status_check (void)
Explanation
Checks the status of the slave.
Sets the status check flag, g_status_confirmation_flag, to 1 when the slave status
check ends normally.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] CSI00_Send_Receive
Synopsis
CSI transmission/reception
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_port.h
r_cg_serial.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void CSI00_Send_Receive (void)
Explanation
Performs the master transmission/reception processing.
Arguments
•None
Return value
•None
Remarks
None

RL78/G13 Handshake-based SPI Master Transmission/Reception
R01AN6883EJ0100 Rev.1.00 Page 20 of 38
June.15.23
[Function Name] CSI00_Send
Synopsis
CSI transmission
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_port.h
r_cg_serial.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void CSI00_Send (void)
Explanation
Performs the master transmission processing.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] CSI00_Receive
Synopsis
CSI reception
Header
r_cg_macrodriver.h
r_cg_cgc.h
r_cg_port.h
r_cg_serial.h
r_cg_timer.h
r_cg_userdefine.h
Declaration
void CSI00_Receive (void)
Explanation
Performs the master reception processing.
Arguments
•None
Return value
•None
Remarks
None
[Function Name] R_CSI00_Send_Receive
Synopsis
CSI00 Transmit/Receive Processing
Header
r_cg_macrodriver.h
、
r_cg_serial.h
、
r_cg_userdefine.h
Declaration
MD_STATUS R_CSI00_Send_Receive(uint8_t * const tx_buf
、
uint16_t tx_num
、
uint8_t * const rx_buf)
Explanation
Configure CSI00 data sending/receiving settings.
Arguments
•uint8_t * const tx_buf
: [Address of sent data buffer]
•uint16_t tx_num
: [Sent data buffer size]
•uint8_t * const rx_buf
: [Address of received data buffer]
Return value
•[MD_OK]
：
Sending/receiving settings complete
•
[MD_ARGERROR]：Sending/receiving settings failure
Remarks
None
[Function Name] r_csi00_interrupt
Synopsis
INICSI00 interrupt processing
Header
r_cg_macrodriver.h
、
r_cg_serial.h
、
r_cg_userdefine.h
Declaration
static void __near r_csi00_interrupt(void)
Explanation
If there is unsent data, reads the received data and starts sending the unsent data. If
there is no unsent data, reads the received data.
Arguments
•None
Return value
•None
Remarks
None