main.cpp

00001 
00002 #include <mbed.h>
00003 #include "smbus.h"
00004 
00005 #define IRQ_OUT_PIN     D6
00006 
00007 const int SLAVE_ADDRESS = 0xA0;
00008 
00009 RawSerial pc(USBTX, USBRX);
00010 
00011 DigitalOut irqOutPin(IRQ_OUT_PIN);
00012 irq_t irq;
00013 
00014 DigitalIn button(USER_BUTTON);
00015 
00016 uint8_t test_buf[32];
00017 
00018 void fill_tx_buf(uint8_t cmd)
00019 {
00020     static uint8_t cnt = 0;
00021     unsigned i;
00022 
00023     /* answering (master read) request here */
00024 
00025     switch (cmd) {
00026         case CMD_TEST3:
00027         case CMD_TEST12:
00028         case CMD_TEST32:
00029             for (i = 0; i < cmd_to_length[cmd]; i++)
00030                 i2c.tx_buf[i] = i + cnt;
00031             cnt++;
00032             break;
00033         case CMD_BUFFER:
00034             memcpy(i2c.tx_buf, test_buf, sizeof(test_buf));
00035             break;
00036         case CMD_IRQ:
00037             for (i = 0; i < cmd_to_length[CMD_IRQ]; i++)
00038                 i2c.tx_buf[i] = irq.buf[i];
00039 
00040             /* interrupt was (is being) read, clear it */
00041             irq.fields.flags.button = 0;
00042             if (irq.buf[0] == 0)
00043                 irqOutPin = 0;
00044 
00045             break;
00046     }
00047 }
00048 
00049 bool cmd_allowed(uint8_t)
00050 {
00051     /* return false if slave cannot take this cmd now */
00052     return true;
00053 }
00054 
00055 void service_i2c_write(uint8_t cmd, uint8_t len, const uint8_t* req)
00056 {
00057     uint8_t s8;
00058 
00059     /* taking master write here */
00060 
00061     switch (cmd) {
00062         case CMD_TEST3:
00063         case CMD_TEST12:
00064         case CMD_TEST32:
00065             for (s8 = 0; s8 < cmd_to_length[cmd]; s8++)
00066                 pc.printf("%02x ", req[s8]);
00067             pc.printf("\r\n");
00068             break;
00069         case CMD_BUFFER:
00070             memcpy(test_buf, req, sizeof(test_buf));
00071             break;
00072         /* failures: */
00073         case CMD_BUSERR:
00074             pc.printf("BUSERR%u\r\n", req[0]);
00075             break;
00076         case CMD_ARLO:
00077             pc.printf("ARLO%u\r\n", req[0]); // req[0] tx_cndtr
00078             break;
00079         case CMD_TIMEOUT:
00080             pc.printf("TIMEOUT%u\r\n", req[0]);    // req[0] tx_cndtr
00081             break;
00082         default:
00083             pc.printf("??%02x??\r\n", cmd);
00084             break;
00085     } // ..switch (cmd)
00086 }
00087 
00088 int main()
00089 {
00090     int res;
00091     bool but;
00092     uint8_t cnt = 0;
00093 
00094     pc.baud(115200);
00095     pc.printf("\r\nreset\r\n");
00096 
00097     res = smbus_init(I2C_SDA, I2C_SCL, SLAVE_ADDRESS);
00098     pc.printf("%d = smbus_init()\r\n", res);
00099 
00100     but = button.read();
00101     while (1) {
00102         service_i2c();
00103 
00104         if (but != button.read()) {
00105             irq.fields.cnt = cnt++;
00106             irq.fields.flags.button = 1;
00107             irqOutPin = 1;
00108 
00109             but = button.read();
00110         }
00111 
00112     } // ..while (1)
00113 }
00114