asynDriver: Asynchronous Driver Support - Release Notes

devEpics/devAsynInt32

Added support for link specification of

@asynMask(portName,addr,nbits,timeout)drvParams

@asyn(portName,addr,timeout)drvParams

nbits > 0  Device is unipolar with a range from 0 to 2^nbits-1 

nbits < 0  Device is bipolar with a range from -2^(abs(nbits)-1) to 2^((abs(nbits)-1)-1
           Values returned on the asynInt32 interface will be sign extended
           using the sign bit (e.g. bit abs(nbits)-1 starting at bit 0).

devEpics/devAsynInt32Array, devAsynFloat64Array

Added support for callbacks from driver to device support. This allows waveform records to have I/O Intr scanning, as already supported for other records in devEpics.

devEpics/asynEpicsUtils

Changed parser so it requires an exact match to "asyn(" or "asynMask(". Previously it tolerated other characters before the "(", and in particular it accepted "asynMask(" when "asyn(" was expected. Note that this change could cause problems with database files if they did not follow the documented syntax, which has no white space between "asyn" or "asynMask" and the "(" character.

asynManager

Fix errors in format strings for asynPrint.

Temporary fix to asynReport thread for Cygwin. If the amount of output is small the thread exists for a very short time, and this causes a crash. The fix is a short wait, but it should really be fixed in base/src/libCom/osi/os/posix/osdThread.c.

testIPServerApp

Fix problem with Makefile.

devGpib

Add more SCPI commands to devGpib template.

drvAsynIPPort

Close sockets on application exit. This is very important for vxWorks, otherwise sockets are not closed cleanly which often leads to problems when the IOC reboots.

drvGsIP488

Hold off SRQ callbacks until iocInit.

drvAsynSerialPort

Clean up operation on POSIX/termios systems (everything but vxWorks). The old mechanism was prone to polling during read operations rather than using the termios read timeout mechanism.

devGpib

asynRecord sets line-buffering on trace file.

Peter Mueller provided code to remove/restore a device from/to the SRQ polling list.

drvGsIP488.c

Clean up dangling 'default' statement.

devGpib

Fixed error in GPIBACMD operations.

linuxGpib

Patches from Gasper Jansa to improve option handling.

devEpics

Fixed null pointer dereference for all device support when SCAN=I/O Intr and asyn port could not be found.

asynRecord

Fixed buffer overflow error when NRRD>40 and IFMT=ASCII.

asynGpib

Read method now sets return status and *eomReason properly.

drvAsynIPPort/drvAsynSerialPort

*eomReason now set to ASYN_EOM_CNT when read count has been satisfied.

Fix timeout settings on RTEMS.

Add support for UDP broadcasts. Specify "UDP*" and the network broadcast address in the port configuration command:
drvAsynIPPortConfigure("L0", "192.168.1.255:1234 UDP*", 0, 0, 0)

drvAsynSerialPort

Full support for new timeout semantics (timeout<0 means "wait forever for characters to arrive", timeout=0 means "return characters immediately available", timeout>0 means "return a timeout status if no characters are received within the specified number of seconds").

drvAsynIPPort/drvAsynSerialPort

Fixed NULL pointer dereference.

drvAsynIPPort

1. Use an EPICS timer to time-out an I/O operation, such as send(), recv() and connect().
2. Periodically check (every 5 seconds) during a long I/O operation to see if the operation should be cancelled.

Item 1) above was not really implemented because there is no portable robust way to abort a pending I/O operation. So the timer set a flag which was checked after the poll() was complete to see if the timeout had occured. This was not robust, because there were competing timers (timeout timer and poll) which could fire in the wrong order.

Item 2) was not implemented, because asyn has no mechanism to issue a cancel request to a driver which is blocked on an I/O operation.

Since neither of these mechanisms was working as designed, the driver has been re-written to simplify it. If one or both of these are to be implemented in the future the code as of version 1.29 should be used as the starting point.

If pasynUser->timeout < 0 an infinite timeout is now used.

Fixed bug so that ports connected with a file descriptor in pasynUser->reason execute code to set timeouts.

Fixed bug to return error if pasynCommon->connect is called when port already connected.

asynTrace

Added two new functions which are related to pasynTrace->print and pasynTrace->printIO the way vprintf is related to printf.

• pasynTrace->vprint Same as pasynTrace->print except that instead of a variable of arguments it takes a va_list argument as its last parameter.
• pasynTrace->vprintIO Same as pasynTrace->printIO except that instead of a variable of arguments it takes a va_list argument as its last parameter.

asynManager

Changed pasynManager->connectDevice for ports which have the properties autoConnect=1 and isConnected=0. In this case a request is queued to call asynCommon->connect for that port. This ensures that ports that have a pasynUser connected to them will report being connected even if no I/O has yet been done. Previously such ports reported a disconnected state until the first I/O or operation such as setTraceMask. This was confusing.

Clarify documentation on meaning of pasynUser->timeout. Previously there was no documented method of specifying an "infinite" timeout to a driver, and the meaning of timeout=0.0 was not defined. The new definitions are:

> 0.0 Wait for up to timeout seconds for the I/O to complete

= 0.0 Peform any I/O that can be done without blocking. Return timeout error if no I/O can be done without blocking.

< 0.0 Infinite timeout. Wait forever for I/O to complete.

devEpics

Fixed bugs with asynFloat64Average device support. The wrong interrupt function was being called, and UDF was not being cleared.

memMalloc/memFree

memMalloc was allocating the amount of memory the caller requested rather than the amount required for the freeList. If memFree was called and the memory reallocated to a user requesting a larger size, memory corruption occured. This is fixed.

SyncIO routines

If the connect call fails the asynUser is no longer freed. Instead a message is put into asynUser.errorMessage. The caller must call disconnect in order to free the storage for the asynUser.

The SyncIO routines no longer call asynPrint if there is an error and there is a valid asynUser available. Rather they return an error message in pasynUser->errorMessage. The SyncIO*Once functions still call asynPrint for errors, because they do not have a way of returning an error message.

Serial, TCP/UDP/IP

Handle 0-length write requests.

TCP/UDP/IP

Added drvAsynIPServerPort to support TCP and UDP socket servers.

Added iocBoot/testIPServer to test TCP server support.

drvAsynIPPort now closes TCP sockets when remote system closes connection.

drvAsynIPPort connect function now uses pasynUser->reason as a file descriptor if it is > 0. This allows drvAsynIPServerPort to re-use asyn ports it creates.

Made drvAsynIPPort add null byte at end of input if there is room.

Made drvAsynIPPort:readRaw set eomReason to 0. It was not setting eomReason at all previously.

Serial

Made drvAsynSerialPort add null byte at end of input if there is room.

Made drvAsynSerialPort:readRaw set eomReason to 0. It was not setting eomReason at all previously.

Interfaces

Added asynCommonSyncIO for synchronous support of the asynCommon interface.

VME GPIB

Add delay loops to get these boards to work with faster VME CPU modules.

VXI11

Better support was provided for VXI-11.3 controllers, i.e. talking directly to an ethernet port on an instrument. In particular a TDS3054B was tested.

WARNING: The VXI-11.1 ansd VXI-11.3 standards do NOT allow access to GPIB lines, i.e. conmmands like Untalk/Unlisten are not possible. The previous support issued these commands after each read or write. Some really old GPIB devices may fail. If so the device specific code must be modified to sent these commands separately.

win32

Changes were made to allow asyn to build on native Windows (win32-x86) architecture.

There are two asyn components that do not yet work on win32-x86.

1. Local serial ports. The asyn uses the "termios" API for serial ports, and termios is not available for native Windows.
2. VXI-11. The asyn VXI-11 support uses the Sun XDR API, which is not available for native Windows.

Users who want to use local serial ports or VXI-11 on Windows can use the Cygwin EPICS build (cygwin-x86).

devGpib: devGpibConvertExample

An example of how to implement convert routines for devGpib support modules is available in asyn/devGpib/devGpibConvertExample.c

devAsynOctet.c

The UDF field is now set FALSE when the VAL field is updated.

asynManager

• lock/unlock renamed to blockProcessCallback/unblockProcessCallback

  The names have been changed and now these methods only work for asynchronous ports. An error is returned if blockProcessCallback is called for a synchronous port.

• lockPort/unlockPort

  These are new asynManager methods. They can be used in place of queueRequest if the caller can block. They have been added to make it easier to implement a driver with one addressing scheme that is a asynUser of a driver with a different addressing scheme. For example a multi-drop serial driver can be implemented that calls a standard serial driver.

• asynLockPortNotify

  This is a new interface for driver's that call other drivers.

cancelInterruptUser

The cancelInterruptUser methods of all interfaces has been changed from

    asynStatus (*cancelInterruptUser)(void *registrarPvt, asynUser *pasynUser);

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

asynTrace

The length and size arguments now have type size_t.

devGpib

Several improvements were made to devSupportGpib.c. All changes should be transparent to code that uses devGpib.

asynOctetBase

The maxchars argument to callInterruptUsers has been removed.

asynReport

The filename argument has been removed.

devAsynFloat64

For asynAoFloat64 it now uses oval instead of val.

asynFloat64Array, asynInt32Array, asynOctet, asynOctetSyncIO

All length and size arguments now have type size_t.

asynFloat64SyncIO, asynInt32SyncIO, asynOctetSyncIO, and asynUInt32DigitalSyncIO

These all use lockPort/unlockPort instead of queueRequest.

devAsynFloat64

Device support was not returning 2 (do not convert) for ai records when it should. This meant that the VAL field was being set back to 0 by the record after device support wrote to it. This bug is fixed.

asynRecord

The record sometimes did not read the current input and output EOS values from the driver when it connected. This bug is fixed.

Acknowledgement

Yevgeny A. Gusev has again reported some hard to recognize bugs. He must have spent many hours looking at the code. His extra set of very good eyes are much appreciated!!. He also thought of the way to handle support that uses one addressing scheme but wants to use support that has a different addressing scheme. For example support for mult-drop serial that wants to use the standard serial support

asynInterposeEos

If read reads maxchars, it forced the last character to be 0 and returned asynOverflow if it wasn't. This is fixed.

drvAsynSerialPort,drvAsynIPPort - Error reporting

These did not properly set an error message in asynUser.errorMessage when they returned asynError. This is fixed.

drvAsynSerialPort - serial port options

Changes were made to the way serial port options are handled.

• initial values

  Previosly defaults were assigned for all options. Now the initial values are fetched from either the termios (POSIX) or sioLib (vxWorks).

• vxWorks clocal and crtscts

  The vxWorks sioLib uses clocal for what POSIX calls crtscts. The new serial support for vxWorks accepts both clocal and crtscts to specify RTSCTS (Request to send, Clear to send).

asynRecord - Serial Port Options

This has a new option to set Modem Control.

The only code change was to fix the drvAsynIPPort and drvAsynSerialPort segmentation faults on cygwin-x86.

Incompatible Changes.

APOLOGY: Many interfaces have changed since release 3-3. This is the reason this release is called 4-0.

• asynManager - Only report has changed. Many new methods have been added. asynManager:report takes an additional parameter, portName.
• asynOctet - The read/write methods are similar to before. The new version has sepearate end of string methods for input and output.
• register based interfaces - Extensive changes have occured.
• devGpib - Unless special conversion routines call low level drivers, debGpib support should work without any changes.
• devEpics -
  • Extensive changes have occured. The support naming now follows the names of asyn interfaces. For example devAsynInt32 contains device support for interface asynInt32.
  • device definitions have changed.

    Blanks no longer appear in the menu choices. For example.

        device(ai,INST_IO,devAiAsynInt32,"asyn Int32")
           

    is now

        device(ai,INST_IO,asynAiInt32,"asynInt32")
           

• asynOctetSyncIO
  • All read and write methods now return asynStatus and have additional args to return the number of bytes sent/received.
• asynRecord
  • The IEOS and OEOS fields are set to the current values for the port when the record connects to the port. If they are modified after the record connects to the port, then the EOS strings will be changed using asynOctet->setOutputEos or asynOctet->setIbputEos. IMPORTANT: The values of IEOS and OEOS in the database file are never used, because they are modified when the record connects to the port.

New Features

• interrupt support -A major new feature is support for interrupts. See asynDriver.html for details.
• linuxGpib - This is support for the linuxGpib open source project. It contains support for many linux gpib kernel drivers. The asyn support was provided by Rok Sabjan (cosyLab).
• cancelRequest - If cancelRequest is called while either the process or timeout callback is active, it now waits until the callback completes.
• asynRecord
  • Added PCNCT field to connect/disconnect from port, and to indicate if port is currently connected.
  • Added DRVINFO and REASON fields to provide control for the drvUser interface.
  • Added support for register interfaces (asynInt32, asynUInt32Digital, and asynFloat64). New I/O fields for this support are I32INP, I32OUT, UI32INP, UI32OUT, UI32MASK, F64INP, and F64OUT. The new IFACE field is used to select the currently active interface.
  • Added new fields to indicate if a particular interface is supported by the driver. These fields are OCTETIV, I32IV, UI32IV, F64IV, OPTIONIV, and GPIBIV.
  • Added support for I/O Intr scanning for any driver/interface that supports callbacks. asynOctet does not yet support callbacks.

Incompatible Changes.

• MAY BE MORE - This release has major new features. Implementing the new features may have caused some imcompatibilities, This list is likely to grow as existing users report problems.
• queueRequest - If the portDriver does not block then the queue callback is called by queueRequest rather than by a separate thread. User code can call canBlock to find out how the callback is called.
• registerPort - The argument multiDevice has been replaced by attributes. Attributes currently has two bits ASYN_MULTIDEVICE and ASYN_CANBLOCK. The port driver is responsible for setting both bits correctly.
• setOption/getOption have been moved from asynCommon to a new interface asynOption.

Major New Features

• Support for synchronous drivers.
• Support for register based drivers.
  • Generic register based device support for EPICS records.
  • Additional fields have been added to asynUser.
  • Added pasynManager->memMalloc() and pasynManager->memFree() for allocating and freeing memory with a freelist. This is primarily meant to be used with pasynManager->duplicateAsynUser() and the new pasynUser->userData field.

asynDriver.h

The following changes have been made

• userData - this is a new field in asynUser.
• registerPort - Field multiDevice is replaced by attributes. Currently two attributes are defined: ASYN_MULTIDEVICE and ASYN_CANBLOCK.
• duplicateAsynUser - This is a new method that creates a new asynUser and initializes it with values from an existing asynUser. freeAsynUser now puts the asynUser of a free list rather than calling free.
• memMalloc/memFree - New methods that manage storage. It uses a set of free lists of different sizes.
• asynCommon no longer has methods setOption/getOption.
• asynOctet is now defined in a separate header file.

asynRecord

Removed the GOPT field. This is no longer necessary because the port options are automatically read whenever connecting to a port. "special" requests are now queued without changing the state of the record, using the new duplicateAsynUser, memMalloc(), and memFree() methods. This means that there is no longer a possibility of a special request being rejected because the record is busy. It is no longer possible to cancel a special request.

asynGpib

• asynGpibPort:srqStatus returns asynStatus
• asynGpibPort:serialPoll returns asynStatus. It now only calls a registered callback only if statusByte&0x40 is non zero.

devSupportGpib

• setEos is now a method.
• completeProcess is a new method. This was added to support synchronous drivers.
• Failures for GPIBREADW|GPIBEFASTIW were not handled properly. This could cause and assert failure. This is fixed.

drvAsynSerialPortFlush

Flushes input only.

asynInterposeEOS

The EOS read method now calls the low-level read method only once and returns as many characters as the low-level method supplies. This makes the EOS read semantics match those of the low-level serial and IP drivers.

drvVxi11

vxi11SetRpcTimeout - now handles fractions of a second properly

asynRecord

A new field has beem added, AQR (Abort Queue Request)

The semantics have been changed as follows: process is responsible for all and only for I/O operations. Only I/O operations cause the alarm status and severity to change. Special is responsible for all other operations performed by asynRecord.

Changed and obsolete features

• INCOMPATIBLE CHANGE -- The units of the respond2Writes field, if greater than 0, are now seconds rather than milliseconds. This change was made so that all time values set in the instrument support initialization routine are specified uniformly in units of seconds. Very few instrument support files are likely to be affected by this change
• The contents of asynRecDevDrv.dbd have been placed in asyn.dbd and asynRecDevDrv.dbd has been removed. This allows applications to get correct dbior reports and access to asynRecords by including any low-level driver .dbd file.
• The drvAsynTCPPort driver has been renamed drvAsynIPPort since it now supports both UDP and TCP protocols. The protocol is selected by adding a "UDP" or "TCP" after the "hostname:port" in the drvAsynIPPortConfigure command. A missing protocol is taken to be "TCP".
• Work around 'missing SPD' bug in HP E2050 GPIB/LAN adapter. SRQ handling is much more robust on all supported hardware.

Major New Features

• National Instruments NI1014 VME GPIB interface is now supported.
• GPIB - All low level GPIB support (vxi11, gsip488, and ni1014) now fully support the GPIB specific features defined by asynGpibDriver.h
• Implementation of asynTrace is more consistent across the low level drivers.
• Added makeSupport script and template instrument support. Updated tutorials to reflect these additions.

Major New Features

Changed and obsolete features

• The drvGenericSerial driver has been split into drvAsynSerialPort and drvAsynTCPPort drivers for local and remote serial ports, respectively. End-of-string processing has been moved to an interposed interface.
• The diagnostic facilities previously provided by asynTrace.db have been replaced with the much more general asynRecord.db
• All asynManager,asynCommon, and asynOctet methods except report now return asynStatus. Methods that previously returned a different value now have an additional argument for this value.
• Low-level driver read and write methods now return asynStatus and are passed an additional argument through which they store the actual number of characters read or written.
• The createSocket method in the asynSyncIO interface has been replaced by openSocket.  openSocket does not call asynSyncIO->connect(), that must now be done by the caller.
• Removed code for "flush" from gpib drivers.  The implementation caused infinite loops on devices that speak when not spoken to.
• asynRecord
  • asynOctetRecord has been renamed to asynRecord
  • TIOM, TMSK, TSIZ, TFIL, AUCT, ENBL, CNCT, ERRS, TINP, NAWT fields have been added
  • Default values of OMAX and IMAX decreased from 512 to 80
  • Options that are unknown for a device (e.g. baud on a Moxa terminal server) are shown as Unknown.
  • Many bug fixes and improvements in logic and functionality

Major New Features

• Connection Management - A framework for connection management is provided. It provides the ability to connect/disconnect to/from a port or port,addr. It also provides enable/disable and autoConnect/noAutoConnect. See the asynDriver for details.
• devAsyn - Generic device support for connect management for a specific device.
• devAsynGeneric - Generic support for connection management and traceing. This support dynamically attaches to a port,addr. Thus one set of records and one medm display can be used for all devices connected to an ioc.
• asynOctetRecord - A generic record and medm display that allows interactive access to many asynDriver features.
• asynSyncIO - A synchronous interface to asynDriver. This can be used by code, e.g. SNC programs, that are willing to wait instead of following an asynchronous model.

Changed and obsolete features

• devAsynTrace is replaced by devAsyn and devAsynGeneric.
• asynManager.h
  • disconnectDevice has been renamed to disconnect.
  • The interface to low level drivers has been drastically modified in order to support the new connection management features. See the asynDriver documentation for details.
• asynGpib
  • registerPort has additional arguments multiDevice and autoConnect.
  • setPortOption,getPortOption are setOption,getOption

• Promote VXI-11 RPC definition files to vxi11 directory. Use rpcgen to build RPC support files for targets for which this is possible.
• Run rpcgen on Solaris with 'multi-thread' flag.
• Use separate GPIB message/response buffer for each port instance.
• Use sscanf to convert GPIB stringin response.
• Fix race condition in GPIB finish routines.

This release includes support for the following:

• asynTrace - A trace facility is now implemented.
• gsIP488 - The Greensprings Industry Pack IP488 is now supported

Modifications include:

1. Added asynSetPortOption and asynGetPortOption to manipulate port options.
2. Changed serial support to use asynSetPortOption/asynGetPortOption.
3. Added devGPIB GPIBCVTIO commmand type to allow custom conversion routine to perform all I/O operations.
4. Changed rules for return value from devGPIB custom conversion routines.
5. Added dbior support.
6. Changed devGPIB to no longer cache EOS.

Support Provided in addition to asynDriver and asynGpib

• devGpib - The Winans/Franksen gpib device support.
• vxi11 - Support for instruments that support the VXI-11 standard.
• drvGenericSerial - Support for devices connected to serial ports or to Ethernet/Serial converter.

Future Support

• Other device support methods especially streams, devSerial, and mpfSerial.
• NI1014 VME Gpib driver.
• Industry Pack IP488 Gpib driver.
• Successor to GI (GPIB Interact).

Testing

The vxi11 support has been tested on the following platforms: Solaris, Linux (redhat 9), Darwin, Windows XP (Cygwin), and vxWorks. It has been tested with the following vxi11 controllers:

• Agilent E2050A LAN/GPIB Gateway.

  It's vxiName must start with "hpib" rather than "gpib".

• Agilent E5810A LAN/GPIB Gateway.
• Tektronix TDS3014B Scope.

  When communicating with the Ethernet port it acts like a VXI-11.2 rather than a VXI-11.3 device. It seems to just accept any GPIB address. SRQs did not work when connecting via the ethernet port but did when communicating via a LAN/GPIB gateway.

The generic serial support has been tested with the following:

• xvWorks with a GreenSprings Octal UART Industry-Pack module on a VME carrier.
• Linux and Windows XP (Cygwin) with PC hardware serial port (/dev/ttyS0).
• Solaris hardware serial port (/dev/cua/a).
• Linux, Solaris, Darwin, vxWorks, and Windows XP (Cygwin) with a Moxa NPort Ethernet/Serial converter.