Diff: main.cpp

Revision:

0:b847a1ffc64f

Child:

1:3c1ad60f5cf3

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Mon Apr 13 14:01:48 2020 +0000
@@ -0,0 +1,91 @@
+#include "mbed.h"
+//#include "SDFileSystem"
+//#include "FastIO.h"
+#include "MODDMA.h"
+
+
+void pllfeed() {
+    __disable_irq();
+    LPC_SC->PLL0FEED=0x000000aa;
+    LPC_SC->PLL0FEED=0x00000055;
+    __enable_irq();    
+}
+void setpll() {
+    // the MBED crystal oscillator is 12 MHz
+    // main oscillator frequency 300 MHz: M = (300 x N) / (2 x 12)
+    int n=2;
+    int m=25;
+    // processor clock 100 MHz = 300 MHz / D
+    int d=3;
+    // disconnect
+    LPC_SC->PLL0CON=0x00000001; pllfeed();
+    // disable
+    LPC_SC->PLL0CON=0x00000000; pllfeed();
+    // set new PLL values
+    LPC_SC->PLL0CFG=((n-1)<<16)|(m-1); pllfeed();
+    // enable
+    LPC_SC->PLL0CON=0x00000001; pllfeed();
+    // set cpu clock divider
+    LPC_SC->CCLKCFG=d-1;
+    // wait for lock
+    while (LPC_SC->PLL0STAT&0x04000000==0);
+    // connect
+    LPC_SC->PLL0CON=0x00000003; pllfeed();
+}
+
+
+DigitalOut led1(LED1);
+DigitalOut led2(LED2);
+
+MODDMA dma;
+
+void TC0_callback(void) {
+    led1 = 1;
+}
+
+Serial test(p13, p14);
+
+int main() {
+    setpll();
+    pllfeed();
+    
+    char s[] = "I2S CCLK/4 Verification Test";
+    
+    //turn on i2s periph
+    LPC_SC -> PCONP |= (1 << 27);
+    
+    //set PCLK_peripheral = CCLK/2; such that bitstream is CCLK/4
+    LPC_SC -> PCLKSEL1 |= (2 << 22);
+    
+    //monaural format; master mode
+    LPC_I2S -> I2SDAO |= (0x8);
+    
+    //connect i2s channel 0 tx to dma
+    LPC_I2S -> I2SDMA1 |= (0x80002);
+    
+    //select p5 pin for i2s tx
+    LPC_PINCON -> PINSEL0 |= (1 << 18);
+
+    
+    MODDMA_Config *config = new MODDMA_Config;
+    config
+     ->channelNum    ( MODDMA::Channel_0 )
+     ->srcMemAddr    ( (uint32_t) &s )
+     ->dstMemAddr    ( 0 )
+     ->transferSize  ( sizeof(s) )
+     ->transferType  ( MODDMA::m2p )
+     ->transferWidth ( 8 )
+     ->srcConn       ( 0 )
+     ->dstConn       ( MODDMA::I2S_Channel_0 )
+     ->dmaLLI        ( 0 )
+     ->attach_tc     ( &TC0_callback )
+    ;
+    
+    dma.Setup(config);
+    dma.Enable(config);
+    while(1) {
+        printf("%d ;", LPC_I2S -> I2SSTATE);
+        wait(0.5);
+    }
+}
+