Sample program for CAN communication using RX microcontroller
A CAN bus transceiver has to be connected to the CAN port.
If there are multiple channels of CAN, the communication channel is switched.
The environment variable "MULTI" is enabled in "main.cpp".
- main.cpp
- RX62N/Makefile
- RX631/Makefile
- RX64M/Makefile
- RX65N/Makefile
- RX71M/Makefile
- RX72N/Makefile
- RX66T/Makefile
- RX72T/Makefile
- README.md
- READMEja.md
- The RXxxx/clock_profile.hpp declares a set frequency for each module.
- Connect the LED to the specified port.
- In the case of the RX72N Envision kit, it utilizes the blue LED on the board.
- Connect the CAN bus transceiver to the CAN port. (CTX0, CRX0)
- Connect the appropriate terminator resistor to the CAN bus transceiver.
- The CAN bus transceiver must be of the 3.3 V operating variety.
See the following sources for the ports to connect the CAN bus transceiver.
For actual connection, refer to the hardware manual for confirmation.
| microcontroller | file | CAN0 Alternate | CAN1 Alternate |
|---|---|---|---|
| RX62N | RX62x/port_map.hpp | FIRST | X |
| RX631 | RX63x/port_map.hpp | FIRST | - |
| RX64M | RX64M/port_map.hpp | FIRST | FIRST |
| RX65N | RX65x/port_map.hpp | FIRST | X |
| RX71M | RX64M/port_map.hpp | FIRST | FIRST |
| RX72N | RX72N/port_map.hpp | X | SECOND |
| RX66T | RX66T/port_map.hpp | FIRST | X |
| RX72T | RX72T/port_map.hpp | FIRST | X |
CAN0:
| microcontroller | FIRST/CRX0 | FIRST/CTX0 | | | SECOND/CRX0 | SECOND/CTX0 |
|---|---|---|---|---|---|
| RX62N | P33 | P32 | | | - | - |
| RX631 | P33 | P32 | | | PD2 | PD1 |
| RX64M | P33 | P32 | | | PD2 | PD1 |
| RX65N | P33 | P32 | | | PD2 | PD1 |
| RX71M | P33 | P32 | | | PD2 | PD1 |
| RX72N | P33 | P32 | | | PD2 | PD1 |
| RX66T | P22 | P23 | | | PA1 | PA0 |
| RX72T | P22 | P23 | | | PA1 | PA0 |
For RX64M (port_map.hpp FIRST candidate)
case peripheral::CAN0:
{
uint8_t sel = enable ? 0b010000 : 0;
PORT3::PMR.B2 = 0;
PORT3::PMR.B3 = 0;
MPC::P32PFS.PSEL = sel; // CTX0 (P32 LQFP176: 29)
MPC::P33PFS.PSEL = sel; // CRX0 (P33 LQFP176: 28)
PORT3::PMR.B2 = enable;
PORT3::PMR.B3 = enable;
}
break;- By changing the CAN port candidate in main.cpp, the assigned port can be changed.
- Basic port settings are prepared in port_map.hpp.
static const auto CAN0_PORT = device::port_map::option::FIRST;
static const auto CAN1_PORT = device::port_map::option::FIRST;- Candidate for operation at 3.3V
- 5V not possible
- Max. 1 Mbit/s
- Power 5V
- I/O 3.3V、5V selectable
- Max. 5 Mbit/s
- Use CAN0, single channel
- Operation check with FRK-RX62N(CQ 出版社)
- Use CAN0, single channel
- Operation check with GR-CITRUS
- Use CAN0/CAN1, Multi-channel support
- Operation check with DIY-board
- Use CAN0, single channel
- Operation check with DIY-board
- The program supports multiple channels, but it is a single channel because it does not have access to the CAN port.
- Use CAN0, single channel
- CN13 (2) P32 (CTX0)
- CN13 (3) P33 (CRX0)
- CN8 (2) 3.3V
- CN8 (4) GND
- CN8 (5) GND
- The program supports multiple channels, but it is a single channel because it does not have access to the CAN port.
- Use CAN1, single channel
- Pmod1 (1) P54_SS (CTX1)
- Pmod1 (7) P55/IRQ10 (CRX1)
- Pmod1 (6) 3.3V
- Pmod1 (12) 3.3V
- Pmod1 (5) GND
- Pmod1 (11) GND
The instance corresponding to CAN0 collects packets by "can_analize" class.
- Collection of arbitrary IDs and information about them.
- Collection of data sequence. (Only the last 8 bytes retrieved)
- Number of times received.
- Mapping of different IDs by std::map.
- Mapping by ID difference by std::map. (The order of display is displayed in an aligned manner.)
- You can also use boost::unordered_map. (In this case, the display order of CAN-IDs is unordered.)
- The execution binary is slightly smaller when using boost::unordered_map. (In that case, the memory allocation is also smaller.)
| Project | RX62N | RX631 | RX64M | RX65N | RX71M | RX72N | RX66T | RX72T |
|---|---|---|---|---|---|---|---|---|
| Operation check | 〇 | 〇 | 〇 | － | － | － | － | 〇 |
Operation check:
Verified communication by actually connecting the CAN bus and communicating with each other.
If the implementation of the port_map class, which depends on the hardware, is appropriate and the compilation passes, there should be no problem.
CAN data can be sent and received interactively.
- Whenever the program is started, all IDs are received.
- IDs are collected in the "can_analizer" class, which uses boost::unoderd_map.
- If the collection of IDs exceeds the memory limit, an eception will be thrown due to lack of memory and a crash is expected.
- The send_loop command sends IDs and data generated by random numbers in succession.
- The function to supplement ID (map) is provided only for channel 0.
- On the RX64M/RX71M, two CAN channels are enabled.
- For CAN1 reception, the received data is always displayed.
- MB-no is the mailbox number.
- Mailbox-related commands are for debugging.
- Received CAN frames are stored in memory and can be checked with the "dump" command.
- When a new data frame arrives with the same ID, it is overwritten and the counter is advanced.
CAN command version: 1.00
ext set ext-id mode
std set std-id mode
send CAN-ID [data...] send data frame
stat MB-no stat MCTLx register (MB-no: 0 to 31)
list MB-no list MBx register (MB-no: 0 to 31)
status list recv/send error count
clear [CAN-ID] clear map
map [CAN-ID] Display all collected IDs
dump CAN-ID dump frame data
send_loop NUM [-rtr] random ID, random DATA, send loop (RTR)
help command list (this)
Input number: nnn decimal, xnnn hexa-decimal, bnnn binary
- If "#define MULTI" is enabled and there is an instance of CAN1, change the current channel.
- Enables or disables the VALID filter.
- Displays a list of valid IDs.
- Enter standard ID mode. (11 bits)
- Enables or disables the extended ID mode. (29 bits)
- Sends a sequence of data with ID.
- If ID only, send remote frame.
- Send a data string of up to 8 bytes.
- Numerical values can be entered in decimal, hexadecimal (prefixed with x), or binary (prefixed with b).
- Display of CAN MCTLx register.
- MB-no is from 0 to 31.
- Display of CAN MBx registers.
- MB-no is 0 to 31.
- Clear the individual ID information of the can_analizer class.
- Clear all collection history of can_analizer class.
- Displays the IDs collected by the can_analizer class.
- Displays the details of individual IDs.
- Displays frame data related to the individual IDs of the can_analizer class.
- The frame data is the last one obtained by the ID.
- Generates an ID with a random number and sends data.
- Specify the number of repeating data transmission.
- Displays a brief description of the command.
main.cpp contains sample code for a filter with a list of IDs that can be passed through.
- This feature is used when the "MULTI" channel is enabled.
- It is applied to instances of CAN1 with multiple channels.
- The filter uses "boost/unordered_set".
- At the beginning of main.cpp, comment out "#define VALID_FILTER" to disable the filter.
- The valid ID table is as follows
- boost::unordered_set.
- IDs can be added, deleted, etc. dynamically.
#include <boost/unordered_set.hpp>
// 有効な ID だけ通すフィルター
typedef boost::unordered_set<uint32_t> VALID;
// typedef const boost::unordered_set<uint32_t> VALID;
VALID valid_{ 0x123, 0x200, 0x300, 0xaaa, 15, 21, 33 };In the main loop, when dispatching the incoming frame of CAN1, check if the ID is valid and ignore invalid IDs.
while(can1_.get_recv_num() > 0) {
auto frm = can1_.get_recv_frame();
#ifdef VALID_FILTER
if(valid_.find(frm.get_id()) != valid_.end()) {
#else
{
#endif
utils::format("\nCAN1:\n");
CAN::list(frm, " ");
}
}- Connect an appropriate CAN bus transceiver to the CAN bus.
- Connect a terminator resistor to the CAN bus.
CAN bus transport SN65HVD230 sample circuit：
- Move to each platform directory and make it.
- Write the led_sample.mot file.
- The LED flashes every 0.25 seconds.
- The terminal makes a serial connection and communicates with interactive commands.