MRMSPI Class Reference

#include <mrmspi.h>

Inheritance diagram for MRMSPI:

Collaboration diagram for MRMSPI:

Public Member Functions
	MRMSPI (volatile unsigned char *base)
virtual	~MRMSPI ()
virtual void	select (unsigned id) OVERRIDE FINAL
	Select numbered device. 0 clears selection. More...
virtual epicsUInt8	cycle (epicsUInt8 in) OVERRIDE FINAL
Public Member Functions inherited from mrf::SPIInterface
	SPIInterface ()
virtual	~SPIInterface ()
virtual void	cycles (size_t nops, const Operation *ops)
double	timeout () const
	timeout in seconds for an individual cycle() More...
void	setTimeout (double t)

Additional Inherited Members
Protected Attributes inherited from mrf::SPIInterface
epicsMutex	mutex

Detailed Description

Definition at line 20 of file mrmspi.h.

Constructor & Destructor Documentation

MRMSPI()

MRMSPI::MRMSPI

(

volatile unsigned char *

base

)

Definition at line 36 of file mrmspi.cpp.

    :base(base)
{}

~MRMSPI()

MRMSPI::~MRMSPI ( )

virtual

Definition at line 40 of file mrmspi.cpp.

{}

Member Function Documentation

cycle()

epicsUInt8 MRMSPI::cycle ( epicsUInt8  in )

virtual

Perform a single SPI transaction

Exceptions

std::runtime_error

on timeout

Implements mrf::SPIInterface.

Definition at line 65 of file mrmspi.cpp.

{
    double timeout = this->timeout();

    if(mrmSPIDebug)
        printf("SPI %02x ", int(in));

    // wait for send ready to be set
    {
        mrf::TimeoutCalculator T(timeout);
        while(T.ok() && !(READ32(base, SPIDCtrl)&SPIDCtrl_SendRdy))
            epicsThreadSleep(T.inc());
        if(!T.ok())
            throw std::runtime_error("SPI cycle timeout2");

        if(mrmSPIDebug)
            printf("(%f) ", T.sofar());
    }

    WRITE32(base, SPIDData, in);

    if(mrmSPIDebug)
        printf("-> ");

    // wait for recv ready to be set
    {
        mrf::TimeoutCalculator T(timeout);
        while(T.ok() && !(READ32(base, SPIDCtrl)&SPIDCtrl_RecvRdy))
            epicsThreadSleep(T.inc());
        if(!T.ok())
            throw std::runtime_error("SPI cycle timeout2");

        if(mrmSPIDebug)
            printf("(%f) ", T.sofar());
    }

    epicsUInt8 ret = READ32(base, SPIDData)&0xff;

    if(mrmSPIDebug) {
        printf("%02x\n", int(ret));
    }
    return ret;
}

select()

void MRMSPI::select ( unsigned  id )

virtual

Select numbered device. 0 clears selection.

Implements mrf::SPIInterface.

Definition at line 43 of file mrmspi.cpp.

{
    if(mrmSPIDebug)
        printf("SPI: select %u\n", id);

    if(id==0) {
        // deselect
        WRITE32(base, SPIDCtrl, SPIDCtrl_OE);
        // wait a bit to ensure the chip sees deselect
        epicsThreadSleep(0.001);
        // disable drivers
        WRITE32(base, SPIDCtrl, 0);
    } else {
        // drivers on w/ !SS
        WRITE32(base, SPIDCtrl, SPIDCtrl_OE);
        // wait a bit to ensure the chip sees deselect
        epicsThreadSleep(0.001);
        // select
        WRITE32(base, SPIDCtrl, SPIDCtrl_OE|SPIDCtrl_SS);
    }
}

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The documentation for this class was generated from the following files:

• mrmspi.h
• mrmspi.cpp