Re: Re: write and read functions in asyn

[高振华 via Tech-talk <tech-talk@aps.anl.gov>]

Hi Mark,

Thanks,

Does the (* write) function in asynInt32.h inherit from the writeIt function in drvAsynSerialPort.c (when accessing a serial port)?

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

{
    ttyController_t *tty = (ttyController_t *)drvPvt;

    int thisWrite;

    int nleft = numchars;

    int timerStarted = 0;

    asynStatus status = asynSuccess;

    assert(tty);

    ...

Gao Zhenhua

-----原始邮件-----
发件人: "Mark Rivers" <rivers@cars.uchicago.edu>
发送时间: 2025-04-11 11:23:41 (星期五)
收件人: "tech-talk@aps.anl.gov" <tech-talk@aps.anl.gov>, 高振华 <gaozh@ihep.ac.cn>
主题: Re: write and read functions in asyn

Those functions are implemented by the asyn driver.  asynInt32.h defines the interface, but the implementation is done in each driver.

They are analogous to C++ pure virtual functions that each derived class must implement.

Mark

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From: Tech-talk <tech-talk-bounces@aps.anl.gov> on behalf of 高振华 via Tech-talk <tech-talk@aps.anl.gov>
Sent: Thursday, April 10, 2025 8:46 PM
To: tech-talk@aps.anl.gov <tech-talk@aps.anl.gov>
Subject: write and read functions in asyn

 

Hi all,

I saw the prototype declarations for the write and read functions in this. h file(asyn/asyn/interfaces/asynInt32.h),

But I couldn't find the bodies of the write and read functions,

Does anyone know where it is?

typedef struct asynInt32 {

    asynStatus (*write)(void *drvPvt, asynUser *pasynUser, epicsInt32 value);

    asynStatus (*read)(void *drvPvt, asynUser *pasynUser, epicsInt32 *value);

    asynStatus (*getBounds)(void *drvPvt, asynUser *pasynUser,

                           epicsInt32 *low, epicsInt32 *high);

    asynStatus (*registerInterruptUser)(void *drvPvt,asynUser *pasynUser,

                           interruptCallbackInt32 callback, void *userPvt,

                           void **registrarPvt);

    asynStatus (*cancelInterruptUser)(void *drvPvt, asynUser *pasynUser,

                           void *registrarPvt);

} asynInt32;

Thanks,

Gao Zhenhua

--

BSRF

Email:gaozh@ihep.ac.cn

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祝好！

高振华

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Email:gaozh@ihep.ac.cn