M J. / Mbed OS SPI_NUCLEO_SLAVE

SPI Master/Slave communication between two NUCLEO module. You can send objects ( float, text, ..etc) between them. These projects should be used together: SPI_NUCLEO_MASTER SPI_NUCLEO_SLAVE

main.cpp@1:d154278f2ca1, 2017-12-06 (annotated)

Committer:
mjm2016
Date:
Wed Dec 06 08:46:12 2017 +0000
Revision:
1:d154278f2ca1
Parent:
0:52f83e5addd7 
bug fixed

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mjm2016 0:52f83e5addd7 1 #include "mbed.h"
mjm2016 0:52f83e5addd7 2 /*
mjm2016 0:52f83e5addd7 3 AUTHOR Mariwan Jalal
mjm2016 0:52f83e5addd7 4 These projects try to make a communications channel between to NUCELO-L476RG
mjm2016 0:52f83e5addd7 5 using SPI protocol (Slave-Master).
mjm2016 0:52f83e5addd7 6 You can send any kind of object and reproduced between the two module
mjm2016 0:52f83e5addd7 7 USE IT AT YOUR OWN RESPONSIBILITY .. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND
mjm2016 0:52f83e5addd7 8
mjm2016 0:52f83e5addd7 9 */
mjm2016 0:52f83e5addd7 10
mjm2016 0:52f83e5addd7 11 /*
mjm2016 0:52f83e5addd7 12 These projects should be used together
mjm2016 0:52f83e5addd7 13 SPI_NUCLEO_MASTER
mjm2016 0:52f83e5addd7 14 SPI_NUCLEO_SLAVE
mjm2016 0:52f83e5addd7 15 */
mjm2016 0:52f83e5addd7 16
mjm2016 0:52f83e5addd7 17 /*
mjm2016 0:52f83e5addd7 18 Slave communication is shifted by one byte. To respond for ex for a START byte,
mjm2016 0:52f83e5addd7 19 you need to put the ACK byte prepared on the bus even before having the START
mjm2016 0:52f83e5addd7 20 byte received by the slave. As the Master write the SPI bus the START Command,
mjm2016 0:52f83e5addd7 21 the prepared byte on the slave SPI bus will be transferred to the Master
mjm2016 0:52f83e5addd7 22 immediately. So, you need to prepare the Slave device to shift the bytes by
mjm2016 0:52f83e5addd7 23 one byte as in the following example.
mjm2016 0:52f83e5addd7 24 */
mjm2016 0:52f83e5addd7 25
mjm2016 0:52f83e5addd7 26
mjm2016 0:52f83e5addd7 27
mjm2016 0:52f83e5addd7 28 Serial pc(USBTX,USBRX);
mjm2016 0:52f83e5addd7 29
mjm2016 0:52f83e5addd7 30
mjm2016 0:52f83e5addd7 31
mjm2016 1:d154278f2ca1 32 #define SPI_DUMMY 0X0000
mjm2016 0:52f83e5addd7 33 #define SPI_CMD 0XADAD //Anything as a CMD code.
mjm2016 1:d154278f2ca1 34 #define SPI_FAULT 0xDD00 //Anything as a part of 16 bit as control byte
mjm2016 0:52f83e5addd7 35
mjm2016 0:52f83e5addd7 36 #ifdef _DEBUG
mjm2016 0:52f83e5addd7 37 extern Serial pc;
mjm2016 0:52f83e5addd7 38 #define DEBUG_MESSAGE(...) pc.printf(__VA_ARGS__)
mjm2016 0:52f83e5addd7 39 #else
mjm2016 0:52f83e5addd7 40 #define DEBUG_MESSAGE(...)
mjm2016 0:52f83e5addd7 41 #endif
mjm2016 0:52f83e5addd7 42
mjm2016 0:52f83e5addd7 43 typedef unsigned char byte;
mjm2016 0:52f83e5addd7 44
mjm2016 0:52f83e5addd7 45 SPISlave slave(SPI_MOSI, SPI_MISO, SPI_SCK ,PA_4);
mjm2016 0:52f83e5addd7 46 int res=0;
mjm2016 0:52f83e5addd7 47 float d,c,e;
mjm2016 0:52f83e5addd7 48
mjm2016 0:52f83e5addd7 49 /*This will be the float number we wish to transfer.
mjm2016 0:52f83e5addd7 50 You can make a struct of multiple variable and send it in the same way*/
mjm2016 0:52f83e5addd7 51
mjm2016 1:d154278f2ca1 52 typedef union {
mjm2016 0:52f83e5addd7 53 float sensor;
mjm2016 0:52f83e5addd7 54 byte SPI_Packet[sizeof(float)];
mjm2016 1:d154278f2ca1 55 }SPI_Packet_t;
mjm2016 0:52f83e5addd7 56
mjm2016 0:52f83e5addd7 57 SPI_Packet_t packet;
mjm2016 0:52f83e5addd7 58 int main()
mjm2016 0:52f83e5addd7 59 {
mjm2016 0:52f83e5addd7 60 pc.printf("Testing is started from slave side\n");
mjm2016 0:52f83e5addd7 61 slave.format(16,0);
mjm2016 0:52f83e5addd7 62 slave.frequency(1000000);
mjm2016 0:52f83e5addd7 63 unsigned short vs=0;
mjm2016 0:52f83e5addd7 64 slave.reply(SPI_DUMMY); // Prime reply
mjm2016 0:52f83e5addd7 65 unsigned short tempVal=0;
mjm2016 0:52f83e5addd7 66 packet.sensor=1000.02; //Value of the float number we wish to communicate
mjm2016 0:52f83e5addd7 67 while(1) {
mjm2016 0:52f83e5addd7 68 if(slave.receive()) {
mjm2016 0:52f83e5addd7 69 tempVal=(unsigned short) slave.read(); //Real command
mjm2016 0:52f83e5addd7 70 printf("----------------\n%x\n",tempVal);
mjm2016 0:52f83e5addd7 71 /*
mjm2016 0:52f83e5addd7 72 The switch is not necessary if you have only one command between
mjm2016 0:52f83e5addd7 73 master-slave. This is useful if you wish to send different
mjm2016 0:52f83e5addd7 74 object depending on the command.
mjm2016 0:52f83e5addd7 75 */
mjm2016 0:52f83e5addd7 76 switch(tempVal){
mjm2016 0:52f83e5addd7 77 case SPI_CMD: { /*Use this if you have different commands
mjm2016 0:52f83e5addd7 78 for sending different objects to the master.*/
mjm2016 0:52f83e5addd7 79 tempVal=(sizeof(float))<<8| packet.SPI_Packet[0];
mjm2016 0:52f83e5addd7 80 pc.printf("Packet=%x\n",tempVal);
mjm2016 0:52f83e5addd7 81 slave.reply(tempVal);
mjm2016 0:52f83e5addd7 82 for(unsigned int i=1; i<sizeof(float); i++){
mjm2016 0:52f83e5addd7 83 while(!(slave.receive()))
mjm2016 0:52f83e5addd7 84 wait_ms(1);
mjm2016 0:52f83e5addd7 85 vs=slave.read(); //Real command
mjm2016 0:52f83e5addd7 86 if (vs==SPI_DUMMY){
mjm2016 0:52f83e5addd7 87 //Continue sending bytes
mjm2016 0:52f83e5addd7 88 {
mjm2016 0:52f83e5addd7 89 tempVal=0x00FF & packet.SPI_Packet[i];
mjm2016 0:52f83e5addd7 90 pc.printf("Packet=%x\n",tempVal);
mjm2016 0:52f83e5addd7 91 slave.reply(tempVal);
mjm2016 0:52f83e5addd7 92 }
mjm2016 0:52f83e5addd7 93 }
mjm2016 0:52f83e5addd7 94 else {
mjm2016 0:52f83e5addd7 95 slave.reply(SPI_FAULT); //ERROR CODE
mjm2016 1:d154278f2ca1 96 break;
mjm2016 0:52f83e5addd7 97 }
mjm2016 0:52f83e5addd7 98 }
mjm2016 0:52f83e5addd7 99 }
mjm2016 0:52f83e5addd7 100
mjm2016 0:52f83e5addd7 101 break;
mjm2016 0:52f83e5addd7 102 }
mjm2016 0:52f83e5addd7 103
mjm2016 0:52f83e5addd7 104 }
mjm2016 0:52f83e5addd7 105
mjm2016 0:52f83e5addd7 106 }
mjm2016 0:52f83e5addd7 107 }