eDMA with SPC560B
Hi all,
I try to get the eDMA Modul working. My starting point is an example code fromthe document ''Qorivva Simple Cookbook “Hello World�? Programs to Exercise Common Features on MPC5500 & MPC5600 Microcontrollers'' which can be found on the freescale homepage.
Their example is as follows:/* main.c - DMA-Block Move example */
/* Rev 0.1 Sept 30, 2004 S.Mihalik, Copyright Freescale, 2004. All Rights Reserved */
/* Rev 1.0 Jul 10 2007 SM - Changed from TCD18 to TCD0 to be MPC5510 compatible */
/* Notes: */
/* 1. MMU not initialized; must be done by debug scripts or BAM */
/* 2. L2SRAM not initialized; must be done by debug scripts */
#include ''mpc563m.h'' /* Use proper include file such as mpc5510.h or mpc5554.h */
const uint8_t SourceData[] = {''Hello World\r''}; /* Source data string */
uint8_t Destination = 0; /* Destination byte */
void initTCD0(void) {
EDMA.TCD[0].SADDR = (vuint32_t) &SourceData; /* Load address of source data */
EDMA.TCD[0].SSIZE = 0; /* Read 2**0 = 1 byte per transfer */
EDMA.TCD[0].SOFF = 1; /* After transfer, add 1 to src addr*/
EDMA.TCD[0].SLAST = -12; /* After major loop, reset src addr*/
EDMA.TCD[0].SMOD = 0; /* Source modulo feature not used */
EDMA.TCD[0].DADDR = (vuint32_t) &Destination; /* Load address of destination */
EDMA.TCD[0].DSIZE = 0; /* Write 2**0 = 1 byte per transfer */
EDMA.TCD[0].DOFF = 0; /* Do not increment destination addr*/
EDMA.TCD[0].DLAST_SGA = 0; /* After major loop, no dest addr change*/
EDMA.TCD[0].DMOD = 0; /* Destination modulo feature not used */
EDMA.TCD[0].NBYTES = 1; /* Transfer 1 byte per minor loop */
EDMA.TCD[0].BITER = 12; /* 12 minor loop iterations */
EDMA.TCD[0].CITER = 12; /* Initialize current iteraction count */
EDMA.TCD[0].D_REQ = 1; /* Disable channel when major loop is done*/
EDMA.TCD[0].INT_HALF = 0; /* Interrupts are not used */
EDMA.TCD[0].INT_MAJ = 0;
EDMA.TCD[0].CITERE_LINK = 0; /* Linking is not used */
EDMA.TCD[0].BITERE_LINK = 0;
EDMA.TCD[0].MAJORE_LINK = 0; /* Dynamic program is not used */
EDMA.TCD[0].E_SG = 0;
EDMA.TCD[0].BWC = 0; /* Default bandwidth control- no stalls */
EDMA.TCD[0].START = 0; /* Initialize status flags */
EDMA.TCD[0].DONE = 0;
EDMA.TCD[0].ACTIVE = 0;
}
void main (void) {
int i = 0; /* Dummy idle counter */
initTCD0(); /* Initialize DMA Transfer Control Descriptor 0 */
EDMA.CR.R = 0x0000E400; /* Use fixed priority arbitration for DMA groups and channels */
EDMA.CPR[0].R = 0x12; /* Channel 0 priorites: group priority = 1, channel priority = 2 */
EDMA.SERQR.R = 0; /* Enable EDMA channel 0 */
EDMA.SSBR.R = 0; /* Set channel 0 START bit to initiate first minor loop transfer */
/* Initate DMA service using software */
while (EDMA.TCD[0].CITER != 1) { /* while not on last minor loop */
/* wait for START=0 and ACTIVE=0 */
while ((EDMA.TCD[0].START == 1) | (EDMA.TCD[0].ACTIVE == 1)) {}
EDMA.SSBR.R = 0; /* Set channel 0 START bit again for next minor loop transfer */
}
while (1) { i++; } /* Loop forever */
}
I adapted it a little bit so that it is at least running. Now I have the problem, that I always get a source bus error. Are there steps, which have to be done before. Specially I have in mind the points:1. MMU not initialized; must be done by debug scripts or BAM
2. L2SRAM not initialized; must be done by debug scripts
Is there an example application for the spc and how do I get it? I have looked in the SPC5Studio but didn't found anything. Thanks for any help kind regards, Dominik