releasenotes

一个通讯程序源码

This is the original RELEASENOTES from FAS 2.08 for reference only.
Read README.FASI. DO NOT CONTACT UWE DOERING REGARDING THIS HACKED VERSION
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

     release 1.1a Sat Nov 11, 1989

     This is an unofficial release as I'm not the original author
     of this async driver.

     Uwe Doering             INET : [e-mail]
     Billstedter Pfad 17 b   UUCP : ...!unido!fub!geminix.in-berlin.de!gemini
     1000 Berlin 20
     Germany

     New Features:

          Added a third minor tty device number for every physical
          port. See description preceding the asyopen function in
          asy.c. Changed the behavior of ttyxx, too.

          Added output hardware handshake support for DSR. Now you
          can do handshake with CTS, DSR or both. Input hardware
          handshake is on if you use at least one of the output
          handshake signals.

          More flexible support of additional interrupt registers
          on mux boards. This is fully configurable now.

          Added support for the CREAD flag. If not set, receiver
          interrupts are still serviced, but the received characters
          are simply thrown away. This is not as elegant as disabeling
          the interrupts themselves, but with the already existing
          driver it was the easiest way, and the most new-bugs-preventing,
          too.

          Added a lot of comments to the source so that the curious
          user can understand why and how things are done.


     Bug Fixes:

          The hang-up-on-last-close flag (HUPCL) was ignored. DTR
          was asserted regardless of this flag.

          Made the detection of CTS and DCD more bullet-proof.
          Especially because between a close and the next open of
          a line, where interrupts are ignored, the software copys of
          CTS and DCD must be set up propperly in the asyopen function
          or the tty line would be blocked under certain circum-
          stances. For similar reasons, there is also a setup in the
          asyparam function.

          Rewrote the input character processing function to work
          according to the TERMIO(7) man page.

          Changed the behavior of BREAK generation to let the
          transmitter drain before TX is set to low.

          Changed line hangup procedure so that the closing
          process returns immediately and doesn't sleep during
          the hangup delay/time. Instead, if an other process tries
          to open the line while hangup is still in progress, this
          process will sleep until hangup is competed.

          With DOS Merge, on MicroPort V/386 3.0e the linker was
          missing the function `init8250'. Reengineered this from
          a disassembler listing of MicroPort's original driver and
          modified it to work with the NS16550A 16-byte FIFO. This
          funktion was added simply to be able to link the kernel.
          DOS Merge's virtual COM ports are still unusable with this
          release, though. To include this function, add a `-DMERGE'
          to the CFLAGS line in your makefile.

          Made a lot of other corrections and enhancements in both
          speed and functionallity. As a result of all my effords
          I think this driver is slightly faster, more versatile
          and much more stable than the original release.

     ------------------------------------------------------------
          
     release 1.1b Sat Nov 25, 1989

     New Features:

          Changed the minor device number scheme again.
          There are now two main groups: The unblocked open
          and the blocked open. Every group has four sub-modes
          and an additional hardware handshake flag. All this
          is coded in the higher four bits of the minor device
          number. Because of this, the maximum of 32 ports was
          reduced to 16 ports so that the port number fits into
          the remaining lower four bits of the minor device number.
          32 dumb ports in a single machine would have been overkill
          anyway. For more details refer to the description in the
          README file.

     ------------------------------------------------------------
          
     release 2.00 Mon Nov 27, 1989

     As this release differs so much from the original version I got,
     I now declare this as independant from the original author
     Jim Murray. This allows me to introduce new release levels
     without wondering whether they will collide with Jim's releases.
     Of course many credits to Jim for writing this software in the
     first place. Without his driver as a base I never would have
     been able to do such kernel driver development.

     Bug Fixes:

          If there were glitches on the hardware handshake lines
          and the DCD line a getty on this port would sometimes
          hang and become an immortal process. I think this was
          because the output buffer wasn't flushed properly
          on carrier loss. I hope I fixed this now. We'll see.

     ------------------------------------------------------------
          
     release 2.01 Tue Nov 28, 1989

     Did some cleanup in the source code.

     I splitted the driver into two parts: The driver itself and
     the file `space.c'.
     `space.c' contains all data structures necessary to configure
     the driver and is compiled at kernel link time. Therefore if you
     change your serial card configuration you simply change `space.c'
     directly in the link kit directory and relink the kernel. No
     driver recompilation or installation is necessary for this.
     But note that whenever you use `make install' your setup in
     the link kit directory is overwritten by the original `space.c'
     file. Therefore you should copy your new `space.c' back to
     the source directory when you are finished with the configuration.

     Renamed the package to `FAS Final Async Solution'. The following
     files have been renamed:
          asy.c          -> fas.c
          asy.h          -> fas.h
          asy_conf-xxxxx -> space-xxxxx

     ISC 386/ix is supported now. There are separate makefiles
     for uPort and ISC to cope with the differences in link kit
     installation.

     Bug Fixes:

          `getty' still hung sometimes on a line with hardware
          handshake. Tried to fix it this time.

     ------------------------------------------------------------
          
     release 2.02 Thu Nov 30, 1989

     Abandoned the distinction between space-xxxxx files with
     and without hardware flow control because this is selected
     by the minor device number now.

     Bug Fixes:

          Set the high and low water marks for hardware input flow
          control to higher values than software flow control. This
          gives precedence to software flow control if both methods
          are used. These marks are self-adjusting and don't need to
          be changed if some flavor of UNIX has a different buffer
          size than the standard 256 characters. Before this change
          concurrent use of both flow controls could cause trouble
          with some high-speed modems. This is fixed now.

          A flush read or write buffer request now also clears the
          receiver or transmitter FIFO, respectively. An ioctl
          call with a TCSETA* command clears the FIFOs, too.

     ------------------------------------------------------------
          
     release 2.03 Fri Dec 01, 1989

     Wrote an installation guide. The driver should be quite
     easy to install now.

     Added tty node configuration files for ISC.

     Hardware input flow control is bound now to the level of the
     receiver ring buffer instead of the UNIX input buffer. This
     has the advantage that buffer size and trigger levels are
     defined in the driver and therefore can be varied as needed.

     New Features:

          Added a boot time status message that shows the init
          state of each port. This tells you immediately what
          ports are found and initted by the driver. Useful to
          determine hardware configuration problems. Look at
          the description in the README file. Thanks to
          Kritt Gierlewsen ([e-mail]) for this proposal.

     ------------------------------------------------------------
          
     release 2.04 Thu Dec 07, 1989

     Did some cleanup in the source.

     Removed the FIFO clear from the ioctl function. We don't want
     to do things there that aren't in the book.

     An ioctl call that switches off the CLOCAL flag will create
     a SIGHUP signal if the carrier is actually missing at this
     time.

     Every device is tested now quite thoroughly during initialization.
     If the test fails the corresponding device keeps unconfigured.

     ------------------------------------------------------------
          
     release 2.05 Sat Jan 13, 1990

     This is the first public release of the FAS driver.

     Special thanks to the sysops of my test sites, Axel Fischer
     ([e-mail]) and Kritt Gierlewsen ([e-mail]).

     FAS is now an independant driver with its own driver name (`fas'),
     major device number, link kit directory and other things necessary
     for a driver. The original asy driver may or may not be linked
     with the kernel. You only need it if you want to access some
     serial devices via the virtual COM ports of the DOS emulator
     (DosMerge or VP/ix) because the FAS driver doesn't have this
     (really vendor dependant) feature.

     The default prefix for tty device node names is `ttyF' now.
     This prevents mix-ups with the device names of the original
     asy driver.

     Dropped the SYSV/AT support. I couldn't test the driver
     for several release generations on uPort SYSV/AT, and because
     there are not very much systems left with that flavor of UNIX
     it doesn't make sense to try to maintain compatibility with it.
     If someone really wants to use this driver on a 286 he has
     to port it himself.

     Improved the transmitter FIFO fill procedure. Now it will try
     harder to fill the FIFO as much as possible to cut down on
     transmitter interrupts.

     Software input flow control (XON/XOFF) is controlled by the driver now.
     It is bound to the level of the receiver ring buffer (as is hardware
     flow control). As usual, it can be switched on and off by the
     IXOFF flag in the termio(7) structure.

     Changed and speeded up the ring buffer -> unix buffer processing.

     For ISC, the getty lines for the inittab file are installed
     by the makefile now.

     The conditional compilation of the function `init8250' (for
     DosMerge) is now controlled by a define in `fas.h'. The compiler
     switch `-DMERGE' is not used any more.

     Improved the documentation.

     The signals used for modem control and hardware flow control are
     fully configurable in the `space.c' file now. Look at `fas.h' for
     possible macros and combinations.