EDMA_Handle hEdmaReloadRcvPing;
EDMA_Handle hEdmaReloadRcvPong;
MCBSP_Handle hMcbsp1; // McBSP1 (codec data) handle
Int16 gXmtChan; // TCC codes (see initEDMA())
Int16 gRcvChan;
/*
* EDMA Config data structure
*/
/* Transmit side EDMA configuration */
EDMA_Config gEdmaConfigXmt = {
EDMA_FMKS(OPT, PRI, HIGH) | // Priority
EDMA_FMKS(OPT, ESIZE, 16BIT) | // Element size
EDMA_FMKS(OPT, 2DS, NO) | // 2 dimensional source?
EDMA_FMKS(OPT, SUM, INC) | // Src update mode
EDMA_FMKS(OPT, 2DD, NO) | // 2 dimensional dest
EDMA_FMKS(OPT, DUM, NONE) | // Dest update mode
EDMA_FMKS(OPT, TCINT, YES) | // Cause EDMA interrupt?
EDMA_FMKS(OPT, TCC, OF(0)) | // Transfer complete code
EDMA_FMKS(OPT, LINK, YES) | // Enable link parameters?
EDMA_FMKS(OPT, FS, NO), // Use frame sync?
(Uint32)&gBufferXmtPing, // Src address
EDMA_FMK (CNT, FRMCNT, NULL) | // Frame count
EDMA_FMK (CNT, ELECNT, BUFFSIZE), // Element count
MCBSP_FMKS(PCR, FSXM, EXTERNAL) | // Framesync- Signal für Sender kommt von extern (Slave)
MCBSP_FMKS(PCR, FSRM, EXTERNAL) | // Framesync- Signal für Empfänger kommt von extern (Slave)
MCBSP_FMKS(PCR, CLKXM, INPUT) | // Takt für Sender kommt von extern (Slave)
MCBSP_FMKS(PCR, CLKRM, INPUT) | // Takt für Empfänger kommt von extern (Slave)
MCBSP_FMKS(PCR, CLKSSTAT, DEFAULT) | // unrelevant da PINS keine GPIOs
MCBSP_FMKS(PCR, DXSTAT, DEFAULT) | // unrelevant da PINS keine GPIOs
MCBSP_FMKS(PCR, FSXP, ACTIVEHIGH) | // Framesync senderseitig ist "activehigh"
MCBSP_FMKS(PCR, FSRP, ACTIVEHIGH) | // Framesync empfängerseitig ist "activehigh"
MCBSP_FMKS(PCR, CLKXP, FALLING) | // Datum wird bei fallender Flanke gesendet
MCBSP_FMKS(PCR, CLKRP, RISING) // Datum wird bei steigender Flanke übernommen
};
/* template for a EDMA configuration */
/* Empfangen */
EDMA_Config configEDMARcv = {
EDMA_FMKS(OPT, PRI, LOW) | // auf beide Queues verteilen
EDMA_FMKS(OPT, ESIZE, 16BIT) | // Element size
EDMA_FMKS(OPT, 2DS, NO) | // kein 2D-Transfer
EDMA_FMKS(OPT, SUM, NONE) | // Quell-update mode -> FEST (McBSP)!!!
EDMA_FMKS(OPT, 2DD, NO) | // 2kein 2D-Transfer
EDMA_FMKS(OPT, DUM, INC) | // Ziel-update mode -> inkrementieren (ping/pong in buffer)
EDMA_FMKS(OPT, TCINT,YES) | // EDMA interrupt erzeugen?
EDMA_FMKS(OPT, TCC, OF(0)) | // Transfer complete code (TCC)
EDMA_FMKS(OPT, LINK, YES) | // Link Parameter nutzen?
EDMA_FMKS(OPT, FS, NO), // Frame Sync nutzen?
EDMA_FMKS(SRC, SRC, OF(0)), // Quell-Adresse
EDMA_FMK(CNT, FRMCNT, NULL) | // Anzahl Frames
EDMA_FMK(CNT, ELECNT, BUFFER_LEN), // Anzahl Elemente
MCBSP_FMKS(PCR, FSXM, EXTERNAL) | // Framesync- Signal für Sender kommt von extern (Slave)
MCBSP_FMKS(PCR, FSRM, EXTERNAL) | // Framesync- Signal für Empfänger kommt von extern (Slave)
MCBSP_FMKS(PCR, CLKXM, INPUT) | // Takt für Sender kommt von extern (Slave)
MCBSP_FMKS(PCR, CLKRM, INPUT) | // Takt für Empfänger kommt von extern (Slave)
MCBSP_FMKS(PCR, CLKSSTAT, DEFAULT) | // unrelevant da PINS keine GPIOs
MCBSP_FMKS(PCR, DXSTAT, DEFAULT) | // unrelevant da PINS keine GPIOs
MCBSP_FMKS(PCR, FSXP, ACTIVEHIGH) | // Framesync senderseitig ist "activehigh"
MCBSP_FMKS(PCR, FSRP, ACTIVEHIGH) | // Framesync empfängerseitig ist "activehigh"
MCBSP_FMKS(PCR, CLKXP, FALLING) | // Datum wird bei fallender Flanke gesendet
MCBSP_FMKS(PCR, CLKRP, RISING) // Datum wird bei steigender Flanke übernommen
};
/* template for a EDMA configuration */
EDMA_Config configEDMARcv =
{
EDMA_FMKS(OPT, PRI, LOW) | // auf beide Queues verteilen
EDMA_FMKS(OPT, ESIZE, 16BIT) | // Element size EIGEN!!!: Im Foliensatz so gefunden, bin aber nicht sicher, hat das überhaupt große Auswirkung?
EDMA_FMKS(OPT, 2DS, NO) | // kein 2D-Transfer
EDMA_FMKS(OPT, SUM, NONE) | // Quell-update mode -> FEST (McBSP)!!!
EDMA_FMKS(OPT, 2DD, NO) | // 2kein 2D-Transfer
EDMA_FMKS(OPT, DUM, INC) | // Ziel-update mode EIGEN!!!: Ziel-Adresse wird nicht aktualisiert, immer die selbe
EDMA_FMKS(OPT, TCINT, YES) | // EDMA interrupt erzeugen? EIGEN!!!: EDMA muss Interrupts erzeugen!
EDMA_FMKS(OPT, TCC, OF(0)) | // Transfer complete code (TCC)
EDMA_FMKS(OPT, LINK, YES) | // Link Parameter nutzen?
EDMA_FMKS(OPT, FS, NO), // Frame Sync nutzen?
EDMA_FMKS(SRC, SRC, OF(0)), // Quell-Adresse
EDMA_FMK (CNT, FRMCNT, NULL) | // Anzahl Frames
EDMA_FMK (CNT, ELECNT, BUFFER_LEN), // Anzahl Elemente
void conf_EDMA(){
/*
* Open EDMA channels to the REVT1 and XEVT1 interrupts
* issued from the MCBSP periphery. The channels still
* need to be configured properly with a parameterset
* and another parameterset that fills the pong Buffer.
*/
hEDMATrx = EDMA_open(EDMA_CHA_XEVT1, EDMA_OPEN_RESET);
/*
* Aquire EDMA tables that hold the reload tables for both,
* transmit and receive side bufferswitch.
*/
hEDMATrxPing = EDMA_allocTable(-1);
hEDMATrxPong = EDMA_allocTable(-1);
/*
* Set the EDMA source address. On the receive side we use
* the MCBSP source address and save it in the EDMA config
* handle. For the transmit side we will have a fixed
* destination but a variable source address, so we need to
* set the destination to a fixed address!
*/
conf_EDMA_oBuf.dst = MCBSP_getXmtAddr(hMcBsp);
/*
* The next step is to find free Transfer complete codes,
* save them to a variable so the EDMA hardware interrupt
* is able to distinguish between the RX and TX complete
* code. We *could* assign those as static codes, but it
* is better coding practice to make it variable to allow
* future expansion of the code.
*/
tccTrxPing = EDMA_intAlloc(-1);
conf_EDMA_oBuf.opt |= EDMA_FMK(OPT, TCC, tccTrxPing);
/*
* Configure the transmit and receive channel to write in the
* ping buffers. The function copies the struct into the
* EDMA parameter RAM. This allows us to reuse the configs
* to set up the reload configuration for the pong buffers.
*/
EDMA_config(hEDMATrx, &conf_EDMA_oBuf);
EDMA_config(hEDMATrxPing, &conf_EDMA_oBuf);
/*
* Now we are ready to configure the reload parametersets
* that will write to the pong buffers after the ping
* buffer is filled with data.
*/
/*
* First we need to set the destination and source of the
* corresponding pong buffers for both sides.
*/
conf_EDMA_oBuf.src = (uint32_t)oBufPong;
/*
* We also need a transfer complete code for the second
* configuration set to show that we indeed have finished
* the transfer to the pong buffers and switch to ping.
* To overwrite the ones written before we need to
* overwrite the whole 32 OPT bits
*/
tccTrxPong = EDMA_intAlloc(-1);
conf_EDMA_oBuf.opt = EDMA_FMKS(OPT, PRI, HIGH) |
EDMA_FMKS(OPT, ESIZE, 32BIT) |
EDMA_FMKS(OPT, 2DS, NO) |
EDMA_FMKS(OPT, SUM, INC) |
EDMA_FMKS(OPT, 2DD, NO) |
EDMA_FMKS(OPT, DUM, NONE) |
EDMA_FMKS(OPT, TCINT, YES) |
EDMA_FMKS(OPT, TCC, OF(0)) |
EDMA_FMKS(OPT, LINK, YES) |
EDMA_FMKS(OPT, FS, NO);
conf_EDMA_oBuf.opt |= EDMA_FMK(OPT, TCC, tccTrxPong);
/*
* Now we can write the pong buffer configs to the parameter RAM
* tables we aquired before by using EDMA_config()..
*/
EDMA_config(hEDMATrxPong, &conf_EDMA_oBuf);
/*
* We now need to link the transfers so the EDMA fires an interrupt
* whenever we finished a job and immediately starts to
* fill the other buffer (ping -> pong -> ping).
*/
EDMA_link(hEDMATrx, hEDMATrxPing);
EDMA_link(hEDMATrxPing, hEDMATrxPong);
EDMA_link(hEDMATrxPong, hEDMATrxPing);
/*
* Now we take precautions and clear all
* the interrupt sources so no interrupt
* can fire because of some wiggling bits
* caused by an unstable supply.
*/
EDMA_intClear(tccTrxPing);
EDMA_intClear(tccTrxPong);
/*
* Lets enable the interrupts, but we aren't
* done yet: There's still the global interrupt
* switch to be toggled by enable_INT() after
* we started the EDMA transfers.
*/
EDMA_intEnable(tccTrxPing);
EDMA_intEnable(tccTrxPong);
}