Simtel MSDOS 1992 December/simtel1292_SIMTEL_1292_Walnut_Creek.iso/msdos/hamradio/cw.arc/CW.DOC

Text File | 1988-10-22 | 14KB | 442 lines

 AAAA MMMMoooorrrrsssseeee CCCCooooddddeeee SSSSeeeennnnddddiiiinnnngggg aaaannnndddd RRRReeeecccceeeeiiiivvvviiiinnnngggg PPPPrrrrooooggggrrrraaaammmm ffffoooorrrr tttthhhheeee IIIIBBBBMMMM----PPPPCCCC

                    _K_e_v_i_n _S_c_h_m_i_d_t, _W_9_C_F
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        _a_n_d _r_e_c_e_i_v_e _i_n_t_e_r_n_a_t_i_o_n_a_l _m_o_r_s_e _c_o_d_e _v_i_a _t_h_e
                    _I_B_M-_P_C _s_e_r_i_a_l _p_o_r_t.










_C_o_p_y_r_i_g_h_t _1_9_8_8 _b_y _K_e_v_i_n _S_c_h_m_i_d_t. _T_h_i_s _d_o_c_u_m_e_n_t _m_a_y _b_e _r_e_p_r_o_d_u_c_e_d
_f_o_r _a_n_y _n_o_n_c_o_m_m_e_r_c_i_a_l _p_u_r_p_o_s_e _a_s _l_o_n_g _a_s _c_r_e_d_i_t _i_s _g_i_v_e_n _t_o _t_h_e _a_u_t_h_o_r.




































                      October 22, 1988





                           - 2 -


_1.  _I_n_t_r_o_d_u_c_t_i_o_n

     This documentation is for CW.C a morse code sending and
receiving  program written in TURBO-C 1.0 (with bug patches)
for the IBM-PC. You should receive the  C  source  with  any
distribution of this documentation.

     DISCLAIMER: CW.C bypasses both  the  BIOS  and  DOS  to
reprogram the serial port hardware and the timer/sound chip.
The author takes no responsibility  for  what  running  this
code  may  do  to  your system. It is provided AS IS with NO
WARRANTEE whatsoever. Run it at your own risk.

     The distribution should contain the files:

     1.   CW.DOC -- this file

     2.   CW.C -- the source program

     3.   CW.INI -- an example initialization file

     4.   CW.EXE -- (optional) a  compiled  version  of  the
          code. If not supplied or you want to know what you
          are using, compile cw.c using TURBO-C.  My command
          line to do this is:
          tcc -Lc:urbocnclude cw.c
          where you need to change  -L  and  -I  options  to
          correspond  to  the  location  of your library and
          include files.

_2.  _S_e_t_u_p _a_n_d _O_p_e_r_a_t_i_o_n

     CW functions as two separate programs one  for  sending
morse  from  the  keyboard and the other for receiving morse
and displaying it on the screen. The two programs  are  very
loosely  coupled.  Morse  is sent by toggling the request to
send line of the RS-232 serial port.  Mark is +12V and space
is  -12V. Similarly morse characters are received by looking
at the clear to send line of the RS-232 port.

     To get started, put CW.EXE in a  subdirectory  and  put
CW.INI  in  the  same subdirectory. Edit the file CW.INI and
put in any commands that you want  executed  at  startup  in
this file. The example file is:
sound off
sound 40
serial 3f8 4
b1  cq cq cq de w9cf w9cf w9cf k
b2  r tnx for call = rst
b3  = qth new york city ny = name kevin = hw?
b4  de w9cf k



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                           - 3 -


These commands first turn off  the  speaker  which  normally
beeps  whenever  an input mark is detected. The frequency of
the beep is set to 40HZ. This will be the frequency  of  the
beep if the sound is turned back on. Next the serial port is
set to com1.  Com1 is the default so this line  is  unneces-
sary.  For  com2 you would use the command serial 2f8 3. See
the serial command below for more information. There are ten
send  buffers. The first 4 are set in the next 4 lines. Each
of these ends with a space so that a space is the last char-
acter  sent. However, this space does not show above. Modify
the buffers to hold whatever you like.

     To test the code, you can loop back the sender  to  the
receiver.  Do this by shorting the clear to send line of the
RS-232 port to the request to send  line.  These  should  be
pins  4 and 5 of a 25 pin connector. Start up CW. The top of
the screen holds help information. The middle of the  screen
is  the  receive  display  and  the  bottom  portion  is the
transmit display. The last line is used as  a  command  line
and will be described later.

     Type something at the keyboard. It should be  displayed
in  the  transmit  region. Now hit the f9 function key. This
will tell the computer to send  the  text  in  the  transmit
queue out the serial port.  Since this is looped back to the
receiver, it should be displayed in the  middle  portion  of
the  screen. If you want to hear the code on the speaker hit
the f1 key. Alternatively, you can leave the sound off  line
out of cw.ini or replace it with sound on. Note, the speaker
is connected to the receive section. Transmitted  characters
will  not  sound the speaker unless it is looped back to the
receiver.

_3.  _H_e_l_p _S_c_r_e_e_n _a_n_d _f_u_n_c_t_i_o_n _k_e_y_s

     The help screen displays the following information:

     1.   auto or man  --  indicating  whether  the  receive
          speed  is  set  by  the  program  by analyzing the
          incoming morse, or by the operator. Manual mode is
          probably  necessary if you want to hook this up to
          a radio.

     2.   dot -- this displays the current  speed  in  words
          per  minute  of  what the code thinks are incoming
          dots.

     3.   dash -- this displays the current speed  in  words
          per  minute  of  what the code thinks are incoming
          dashs.




                      October 22, 1988





                           - 4 -


     4.   el sp -- this displays the current speed in  words
          per minute of the spaces between dots and dashes.

     5.   lt sp -- this displays the current speed in  words
          per minute of the spaces between letters.

     6.   rcv -- this displays the approximate receive speed
          in words per minute if the program is set to auto.
          In manual  mode,  it  displays  the  manually  set
          receive speed.

     7.   The other items are a quick reference to what  the
          function  keys  do,  and  how  to get command line
          help.

     The 10 function keys are set up as follows:

     f1.  -- toggles the speaker on and off.

     f2.  -- toggles the receive  speed  from  automatic  to
          manual.

     f3.  -- in manual mode decreases the receive speed.

     f4.  -- in manual mode increases the receive speed.

     f5.  -- increases the transmit speed.

     f6.  -- decreases the transmit speed.

     f7.  -- set transmit speed to current receive speed.

     f8.  -- enter a command in command mode.

     f9.  -- toggle from send mode to  hold  mode.  In  hold
          mode, text is entered in the transmit queue but is
          not sent until send mode is toggled.

     f10. -- exit from CW program.

     Shift-f?.
          -- i.e. hold down  the  shift  and  function  key,
          where  ?  is 1 through 10 causes the corresponding
          numbered buffer to be  appended  to  the  transmit
          queue.

     CTRL-f?.
          -- i.e. hold down the control key and the function
          key. This erases the contents of the corresponding
          numbered buffer and prompts for new text.   It  is
          usually  a  good  idea to end text with a space. A



                      October 22, 1988





                           - 5 -


          carriage return (enter key) terminates the text.

     ALT-f?.
          -- i.e. hold down the alt  key  and  the  function
          key.   This  displays  the  current  text  in  the
          corresponding numbered buffer.

_4.  _C_o_m_m_a_n_d_s

     The following commands are allowed in command mode. Any
command listed here may also be used in the startup file.

          read filename -- reads in the  filename  specified
          and sends it.

          sound on -- turns on the speaker.

          sound off -- turns off the speaker.

          sound nnnn -- where nnnn is  a  number,  sets  the
          sound frequency to nnnn.

          receive  automatic  --  set   receive   speed   to
          automatic.

          receive manual -- set receive speed to manual.

          receive nn -- where nn is a number,  sets  receive
          speed to nn words per minute.

          serial hhhh h -- sets the serial port. hhhh is the
          serial  port  base  address  in  hex  and h is the
          hardware interrupt vector used by the serial port.
          Initially,  this  is  set to 3f8 4 which is normal
          for com1. Com2 uses 2f8 3. For other serial  ports
          you  will have to fill in the correct values.  You
          should also check the  interrupt  handler  in  the
          source code to make sure it does what you want.

          stretch nnnn -- where nnnn is  a  number,  reduces
          marks    and    increases   spaces   by   nnnn*840
          nanoseconds. This can be helpful to compensate for
          pulse stretching in audio filters.

          bn text -- where n is a number from 1 to 10, fills
          corresponding buffer with text where text is what-
          ever is to be sent.

          transmit on --  tells  program  to  send  text  in
          transmit queue (see f9 above).




                      October 22, 1988





                           - 6 -


          transmit off -- tells  program  to  hold  text  in
          transmit queue (see f9 above).

_5.  _T_h_e_o_r_y _o_f _O_p_e_r_a_t_i_o_n

     Only a very brief theory of operation will be given.

     The program can be divided into three parts. The  first
part is an interrupt handler for the serial port. The serial
port is set to interrupt on change of the modem  status.  In
particular,  this  happens  when  the  clear to send line is
changed. The interrupt handler simply records the status  of
the  clear to send line in queue.mark and the time since the
clear to send line last changed in queue.mstime  and  incre-
ments  the  queue  pointer countin. The serial port stuff is
fairly standard and I used the description given  by  of  R.
Jourdain,  "Programmer's  Problem  Solver for the IBM PC,XT,
and AT", (Prentice Hall, 1986,  NY)  although  he  gets  the
interrupt  numbers  wrong.   The  method used for timing the
marks and spaces is adapted from B. Sheppard, "High  Perfor-
mance Software Analysis on the IBM PC", BYTE, January 1987.

     The second part of the code is a  replacement  for  the
IRQ0  timer  interrupt.  I  change  the  timer  to interrupt
SPEEDUP times faster than original. Every SPEEDUP interrupts
the  old interrupt handler is called so that disk operations
and the bios date should  be  unaffected.   The  replacement
interrupt handler takes characters from a queue and keys the
request to send line of the serial port. Note  if  you  only
want to receive morse this replacement routine is not neces-
sary  since  microsecond  receive  timing  accuracy  can  be
obtained   without  changing  this  interrupt.  Just  change
SPEEDUP to 1. Note SPEEDUP must be a power of 2.

     The last part of the code is the human interface, which
looks  at  the  receive  queue and displays the result along
with some statistics, and also fills the transmit queue.

     The code has been tested on my 6MHZ ibm  pc-at  running
dos 3.1 with CGA and serial/parallel adaptor and on a zenith
z-181 portable.  Any other  80  column  or  greater  display
should work. Since the clock chip is reprogrammed and serial
port interrupts are used, probably only hardware as well  as
bios  level  clones of the IBM PC will run this code. If you
are attempting to run this code on a particularly  slow  PC,
you  may want to set SPEEDUP to 1 to start. After everything
is working correctly, increase speedup to  get  the  desired
set  of  transmit  speeds.  The possible transmit speeds are
given by dot length = N*840ns*65536/(SPEEDUP) where N is  an
integer,  ns  stands  for nanoseconds, and SPEEDUP must be a
power of 2 for proper operation.



                      October 22, 1988





                           - 7 -


     Most of the information in this section is contained in
the  source  code  comments, which also give some additional
information.

_6.  _C_o_n_c_l_u_s_i_o_n

     I originally wrote this code as a tool  to  help  teach
morse.  By  hooking  a  code key to toggle the clear to send
line, the student can see what she is sending and get a fair
idea  if  her  spacing  is  correct. The sending portion was
added when I needed a cw keyboard for my transmitter.

     I have connected the PC  to my receiver. It  is  fairly
easy  to  receive strong signals using machine produced code
like that from W1AW, but much more difficult  to  deal  with
noisy signals and hand sending.

     I do not plan to work on this code in the future.  How-
ever,  if  you  have  questions,  I  can  be contacted at my
address listed in the call book.


































                      October 22, 1988