ASYN driver for National Instruments VISA. More...

#include <string.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <osiUnistd.h>
#include <cantProceed.h>
#include <errlog.h>
#include <iocsh.h>
#include <epicsAssert.h>
#include <epicsExit.h>
#include <epicsStdio.h>
#include <epicsString.h>
#include <epicsThread.h>
#include <epicsTime.h>
#include <iostream>
#include <string>
#include <visa.h>
#include "asynDriver.h"
#include "asynOctet.h"
#include "asynOption.h"
#include "asynInterposeCom.h"
#include "asynInterposeEos.h"
#include <epicsExport.h>
#include "drvAsynVISAPort.h"

Classes
struct	visaDriver_t
	driver private data structure More...

Macros
#define	VI_CHECK_ERROR(__command, __err)

Functions
static std::string	errMsg (ViSession vi, ViStatus err)
	translate VISA error code to readable string More...

static asynStatus	getOption (void drvPvt, asynUser pasynUser, const char key, char val, int valSize)
	asynOption interface - get options More...

static asynStatus	setOption (void drvPvt, asynUser pasynUser, const char key, const char val)
	asynOption interface - set options More...

static asynStatus	closeConnection (asynUser pasynUser, visaDriver_t driver, const char *reason)
	close a VISA session More...

static void	asynCommonReport (void drvPvt, FILE fp, int details)
	asynCommon interface - Report link parameters More...

static void	visaCleanup (void *arg)

static void	driverCleanup (visaDriver_t *driver)

static asynStatus	connectIt (void drvPvt, asynUser pasynUser)
	create a link More...

static asynStatus	asynCommonConnect (void drvPvt, asynUser pasynUser)

static asynStatus	asynCommonDisconnect (void drvPvt, asynUser pasynUser)

static asynStatus	writeIt (void drvPvt, asynUser pasynUser, const char data, size_t numchars, size_t nbytesTransfered)
	write values to device More...

static asynStatus	readIt (void drvPvt, asynUser pasynUser, char data, size_t maxchars, size_t nbytesTransfered, int *gotEom)
	read values from device More...

static asynStatus	flushIt (void drvPvt, asynUser pasynUser)
	flush device More...

epicsShareFunc int	drvAsynVISAPortConfigure (const char portName, const char resourceName, unsigned int priority, int noAutoConnect, int noProcessEos, int readIntTmoMs, const char *termCharIn, int deviceSendsEOM)
	Create a VISA device. More...

static void	drvAsynVISAPortConfigureCallFunc (const iocshArgBuf *args)

static void	drvAsynVISAPortConfigureRegister (void)

	epicsExportRegistrar (drvAsynVISAPortConfigureRegister)

Variables
static struct asynOption	asynOptionMethods = { setOption, getOption }

static asynOctet	asynOctetMethods = { writeIt, readIt, flushIt }

static struct asynCommon	asynCommonMethods

static const iocshArg	drvAsynVISAPortConfigureArg0 = { "portName",iocshArgString}
	A name for the asyn driver instance we will create e.g. "L0". More...

static const iocshArg	drvAsynVISAPortConfigureArg1 = { "resourceName",iocshArgString}
	VISA resource name to connect to e.g. "GPIB0::3::INSTR" or "COM10". More...

static const iocshArg	drvAsynVISAPortConfigureArg2 = { "priority",iocshArgInt}
	Driver priority. More...

static const iocshArg	drvAsynVISAPortConfigureArg3 = { "noAutoConnect",iocshArgInt}
	Should the driver automatically connect to the device (0=yes) More...

static const iocshArg	drvAsynVISAPortConfigureArg4 = { "noProcessEos",iocshArgInt}
	Should the driver interpose layer be called for EOS (termination) character processing (0=yes) If you have no termination character specified to asyn, then passing 1 (=no) may improve efficiency. More...

static const iocshArg	drvAsynVISAPortConfigureArg5 = { "readIntTmoMs",iocshArgInt}
	internal read timeout (ms) used instead of a zero timeout immediate read. More...

static const iocshArg	drvAsynVISAPortConfigureArg6 = { "termCharIn",iocshArgString}
	read termination character, this is purely to improve read efficiency and is independent of any characters specified at the asyn or stream device later. More...

static const iocshArg	drvAsynVISAPortConfigureArg7 = { "deviceSendsEOM",iocshArgInt}
	Indicates that the device signals an "end of message". More...

static const iocshArg *	drvAsynVISAPortConfigureArgs []

static const iocshFuncDef	drvAsynVISAPortConfigureFuncDef

Detailed Description

ASYN driver for National Instruments VISA.

Definition in file drvAsynVISAPort.cpp.

Macro Definition Documentation

#define VI_CHECK_ERROR	(	__command,
		__err
	)

Value:

if (__err < 0) \
    { \
        epicsSnprintf(pasynUser->errorMessage,pasynUser->errorMessageSize, \
                              "%s: %s %s", driver->resourceName, __command, errMsg(driver->vi, err).c_str()); \
        return asynError; \
    }

Definition at line 67 of file drvAsynVISAPort.cpp.

Referenced by connectIt(), getOption(), readIt(), setOption(), and writeIt().

Function Documentation

static asynStatus asynCommonConnect	(	void *	drvPvt,
		asynUser *	pasynUser
	)

static

Definition at line 559 of file drvAsynVISAPort.cpp.

References connectIt().

static asynStatus asynCommonDisconnect	(	void *	drvPvt,
		asynUser *	pasynUser
	)

static

Definition at line 570 of file drvAsynVISAPort.cpp.

References closeConnection().

static void asynCommonReport	(	void *	drvPvt,
		FILE *	fp,
		int	details
	)

static

asynCommon interface - Report link parameters

Definition at line 396 of file drvAsynVISAPort.cpp.

References visaDriver_t::connected, visaDriver_t::deviceSendsEOM, visaDriver_t::isGPIB, visaDriver_t::isSerial, visaDriver_t::nReadBytes, visaDriver_t::nReadCalls, visaDriver_t::nWriteBytes, visaDriver_t::nWriteCalls, visaDriver_t::readIntTimeout, visaDriver_t::resourceName, and visaDriver_t::termCharIn.

static asynStatus closeConnection	(	asynUser *	pasynUser,
		visaDriver_t *	driver,
		const char *	reason
	)

static

close a VISA session

Definition at line 371 of file drvAsynVISAPort.cpp.

References visaDriver_t::connected, visaDriver_t::resourceName, and visaDriver_t::vi.

Referenced by asynCommonDisconnect(), readIt(), and writeIt().

static asynStatus connectIt	(	void *	drvPvt,
		asynUser *	pasynUser
	)

static

create a link

Definition at line 457 of file drvAsynVISAPort.cpp.

References visaDriver_t::connected, visaDriver_t::defaultRM, errMsg(), visaDriver_t::isGPIB, visaDriver_t::isSerial, visaDriver_t::resourceName, visaDriver_t::termCharIn, visaDriver_t::vi, and VI_CHECK_ERROR.

Referenced by asynCommonConnect().

static void driverCleanup ( visaDriver_t * driver )

static

Definition at line 445 of file drvAsynVISAPort.cpp.

References visaDriver_t::portName, and visaDriver_t::resourceName.

Referenced by drvAsynVISAPortConfigure().

epicsShareFunc int drvAsynVISAPortConfigure	(	const char *	portName,
		const char *	resourceName,
		unsigned int	priority,
		int	noAutoConnect,
		int	noProcessEos,
		int	readIntTmoMs,
		const char *	termCharIn,
		int	deviceSendsEOM
	)

Create a VISA device.

Parameters

[in]	portName	A name for the asyn driver instance we will create e.g. "L0".
[in]	resourceName	VISA resource name to connect to e.g. "GPIB0::3::INSTR" or "COM10".
[in]	priority	Driver priority.
[in]	noAutoConnect	Should the driver automatically connect to the device (0=yes)
[in]	noProcessEos	Should the driver interpose layer be called for EOS (termination) character processing (0=yes) If you have no termination character specified to asyn, then passing 1 (=no) may improve efficiency.
[in]	readIntTmoMs	internal read timeout (ms) used instead of a zero timeout immediate read. Stream device will use such a timeout to flush the input buffer prior to a write, also the driver may use it internally to check for bytes. If you get problems with 0 as this value, try either a small positive number, or if you set it to a negative number then any read call with zero timeout will be replaced with a viFlush() call to clear the input buffer. Such an assumption is valid for stream device, not necessarily for other drivers. Note that for GPIB/ENET we found that such zero timeout reads of no data took much longer than normal reads, hence the option to skip them via a negative timeout.
[in]	termCharIn	read termination character, this is purely to improve read efficiency and is independent of any characters specified at the asyn or stream device later. It allows a read to terminate early without waiting for a timeout, if the calling layer is stream device then it will still decide whether it has all the correct characters or not.
[in]	deviceSendsEOM	Indicates that the device signals an "end of message". If this is true, then the driver can assume that a VI_SUCCESS call translate to ASYN_EOM_END and this will stop a further call from Stream device if there are no termination characters to otherwise know all output has been received. GPIB devices usually signal END, RS232 serial devices do not and you need to look for a termination character instead etc.

Definition at line 893 of file drvAsynVISAPort.cpp.

References asynCommonMethods, asynOctetMethods, asynOptionMethods, visaDriver_t::common, visaDriver_t::connected, visaDriver_t::defaultRM, visaDriver_t::deviceSendsEOM, driverCleanup(), visaDriver_t::flush_on_write, visaDriver_t::isGPIB, visaDriver_t::isSerial, visaDriver_t::octet, visaDriver_t::option, visaDriver_t::pasynUser, visaDriver_t::portName, visaDriver_t::readIntTimeout, visaDriver_t::resourceName, visaDriver_t::termCharIn, visaDriver_t::timeout, and visaCleanup().

Referenced by drvAsynVISAPortConfigureCallFunc().

static void drvAsynVISAPortConfigureCallFunc ( const iocshArgBuf * args )

static

Definition at line 1069 of file drvAsynVISAPort.cpp.

References drvAsynVISAPortConfigure().

Referenced by drvAsynVISAPortConfigureRegister().

static void drvAsynVISAPortConfigureRegister ( void )

static

Definition at line 1079 of file drvAsynVISAPort.cpp.

References drvAsynVISAPortConfigureCallFunc(), and drvAsynVISAPortConfigureFuncDef.

epicsExportRegistrar ( drvAsynVISAPortConfigureRegister )

static std::string errMsg	(	ViSession	vi,
		ViStatus	err
	)

static

translate VISA error code to readable string

Definition at line 60 of file drvAsynVISAPort.cpp.

Referenced by connectIt(), readIt(), and writeIt().

static asynStatus flushIt	(	void *	drvPvt,
		asynUser *	pasynUser
	)

static

flush device

Definition at line 849 of file drvAsynVISAPort.cpp.

References visaDriver_t::connected, and visaDriver_t::resourceName.

static asynStatus getOption	(	void *	drvPvt,
		asynUser *	pasynUser,
		const char *	key,
		char *	val,
		int	valSize
	)

static

asynOption interface - get options

Definition at line 79 of file drvAsynVISAPort.cpp.

References visaDriver_t::connected, visaDriver_t::isSerial, visaDriver_t::pasynUser, visaDriver_t::portName, visaDriver_t::resourceName, visaDriver_t::vi, and VI_CHECK_ERROR.

static asynStatus readIt	(	void *	drvPvt,
		asynUser *	pasynUser,
		char *	data,
		size_t	maxchars,
		size_t *	nbytesTransfered,
		int *	gotEom
	)

static

read values from device

Definition at line 662 of file drvAsynVISAPort.cpp.

References closeConnection(), visaDriver_t::connected, visaDriver_t::deviceSendsEOM, errMsg(), visaDriver_t::nReadBytes, visaDriver_t::nReadCalls, visaDriver_t::readIntTimeout, visaDriver_t::resourceName, visaDriver_t::timeout, visaDriver_t::vi, and VI_CHECK_ERROR.

static asynStatus setOption	(	void *	drvPvt,
		asynUser *	pasynUser,
		const char *	key,
		const char *	val
	)

static

asynOption interface - set options

Definition at line 198 of file drvAsynVISAPort.cpp.

References visaDriver_t::connected, visaDriver_t::flush_on_write, visaDriver_t::isSerial, visaDriver_t::pasynUser, visaDriver_t::portName, visaDriver_t::resourceName, visaDriver_t::vi, and VI_CHECK_ERROR.

static void visaCleanup ( void * arg )

static

Definition at line 428 of file drvAsynVISAPort.cpp.

References visaDriver_t::defaultRM, visaDriver_t::pasynUser, and visaDriver_t::portName.

Referenced by drvAsynVISAPortConfigure().

static asynStatus writeIt	(	void *	drvPvt,
		asynUser *	pasynUser,
		const char *	data,
		size_t	numchars,
		size_t *	nbytesTransfered
	)

static

write values to device

Definition at line 579 of file drvAsynVISAPort.cpp.

References closeConnection(), visaDriver_t::connected, errMsg(), visaDriver_t::flush_on_write, visaDriver_t::nWriteBytes, visaDriver_t::nWriteCalls, visaDriver_t::resourceName, visaDriver_t::timeout, visaDriver_t::vi, and VI_CHECK_ERROR.

Variable Documentation

struct asynCommon asynCommonMethods

static

Initial value:

= {
    asynCommonReport,
    asynCommonConnect,
    asynCommonDisconnect
}

Definition at line 876 of file drvAsynVISAPort.cpp.

Referenced by drvAsynVISAPortConfigure().

asynOctet asynOctetMethods = { writeIt, readIt, flushIt }

static

Definition at line 871 of file drvAsynVISAPort.cpp.

Referenced by drvAsynVISAPortConfigure().

struct asynOption asynOptionMethods = { setOption, getOption }

static

Definition at line 367 of file drvAsynVISAPort.cpp.

Referenced by drvAsynVISAPortConfigure().

const iocshArg drvAsynVISAPortConfigureArg0 = { "portName",iocshArgString}

static

A name for the asyn driver instance we will create e.g. "L0".

Definition at line 1031 of file drvAsynVISAPort.cpp.

const iocshArg drvAsynVISAPortConfigureArg1 = { "resourceName",iocshArgString}

static

VISA resource name to connect to e.g. "GPIB0::3::INSTR" or "COM10".

Definition at line 1033 of file drvAsynVISAPort.cpp.

const iocshArg drvAsynVISAPortConfigureArg2 = { "priority",iocshArgInt}

static

Driver priority.

Definition at line 1035 of file drvAsynVISAPort.cpp.

const iocshArg drvAsynVISAPortConfigureArg3 = { "noAutoConnect",iocshArgInt}

static

Should the driver automatically connect to the device (0=yes)

Definition at line 1037 of file drvAsynVISAPort.cpp.

const iocshArg drvAsynVISAPortConfigureArg4 = { "noProcessEos",iocshArgInt}

static

Should the driver interpose layer be called for EOS (termination) character processing (0=yes) If you have no termination character specified to asyn, then passing 1 (=no) may improve efficiency.

Definition at line 1040 of file drvAsynVISAPort.cpp.

const iocshArg drvAsynVISAPortConfigureArg5 = { "readIntTmoMs",iocshArgInt}

static

internal read timeout (ms) used instead of a zero timeout immediate read.

Stream device will use such a timeout to flush the input buffer prior to a write, also the driver may use it internally to check for bytes. If you get problems with 0 as this value, try either a small positive number, or if you set it to a negative number then any read call with zero timeout will be replaced with a viFlush() call to clear the input buffer. Such an assumption is valid for stream device, not necessarily for other drivers. Note that for GPIB/ENET we found that such zero timeout reads of no data took much longer than normal reads, hence the option to skip them via a negative timeout.

Definition at line 1048 of file drvAsynVISAPort.cpp.

const iocshArg drvAsynVISAPortConfigureArg6 = { "termCharIn",iocshArgString}

static

read termination character, this is purely to improve read efficiency and is independent of any characters specified at the asyn or stream device later.

It allows a read to terminate early without waiting for a timeout, if the calling layer is stream device then it will still decide whether it has all the correct characters or not.

Definition at line 1052 of file drvAsynVISAPort.cpp.

const iocshArg drvAsynVISAPortConfigureArg7 = { "deviceSendsEOM",iocshArgInt}

static

Indicates that the device signals an "end of message".

If this is true, then the driver can assume that a VI_SUCCESS call translate to ASYN_EOM_END and this will stop a further call from Stream device if there are no termination characters to otherwise know all output has been received. GPIB devices usually signal END, RS232 serial devices do not and you need to look for a termination character instead etc.

Definition at line 1057 of file drvAsynVISAPort.cpp.

const iocshArg* drvAsynVISAPortConfigureArgs[]

static

Initial value:

= {
    &drvAsynVISAPortConfigureArg0, &drvAsynVISAPortConfigureArg1, &drvAsynVISAPortConfigureArg2,
    &drvAsynVISAPortConfigureArg3, &drvAsynVISAPortConfigureArg4, &drvAsynVISAPortConfigureArg5,
    &drvAsynVISAPortConfigureArg6, &drvAsynVISAPortConfigureArg7
}