Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/~phil/hardware/vertex/hagenDocmemos/jonedit.txt Дата изменения: Tue Feb 13 22:09:04 2001 Дата индексирования: Thu Jan 15 04:01:25 2009 Кодировка: Поисковые слова: interstellar medium

STEP5 EDITING HINTS
JBH 9-28-00 printed 2-13-01

The STEP5/PC development system makes for awkward editing.
This may be due, in part, to our use of a standard PC rather
than the Siemens custom Programmer PC. Getting around the
menus from one field to another is sometimes difficult, but
not as difficult as editing a field, once you are there. The
editor essentially gives you no prompts; You have to know what
can be entered. A non-acceptable entry, followed by RETURN will
often cause the entry to be erased - purged! Or you may be
answered with a cryptic error message, perhaps "Error No. XX"
for which there seems to be no written key or online help.

Reasons why your entry may not be acceptable:

1. You have used an instruction that is ok in an FB, but not
allowed in an OB or PB.

2. You have written JU FBxx but you have not filled the rest
of this function call: the name of the Fb and the argument list
(which is *** in the case of no arguments).


Comments: Three types of comment can appear in your program:
statement comments, segment comments, and symbolic comments.

Statement comments are those that you enter while editing the
program. They appear to the right of the statement. (See below
for how to access the comment field to enter a comment).

Segment comments form headings for program segments. They are also
entered while using the editor.

Symbol comments are those that have been entered in the
"assignments" file. Suppose that, in the symbols table, you have
assigned the symbol "pwrflag to F10.1, along with a comment
"pwrflag is for the dc supply". In your program, any line that
refers to the F10.0 or "pwrflag" will cause the comment in
the assignent file to appear in your program file. A function key
in the editor allows the editing screen to display either symbol
comments or statement comments, but not both. A print-out of the
program, however, can contain both. The function key, Shift F4,
actually cycles through three options: statement and segment
comments are displayed, symbol and segment comments are displayed,
and no comments are displayed.

It is tricky to enter statement comments. As you edit a line of code,
you must move the cursor to the extreme right side of the operand
field, using the space bar or the tab key. Once you are at the far
right of this field, hit the space bar and you will be at the
beginning of the comment field.

Labels on statments: To jump around in the code, you need
statements such as "JU =CAT". Here, "CAT" is a label on another
statement, e.g. "CAT :A -PWRFLAG" Note that the jump statemnt
must refer to CAT as "=CAT". Note also the dash before "PWRFLAG";
without the dash, the system doesn't have enough sense to look
for an otherwise unidentified symbol in its symbol table.

Shift F3 puts the editor in symbol mode or absolute mode. These are
display options. If you switch to symbol mode, every "F10.0" on
the screen will become "-PWRFLAG". If you switch back to absolute
mode, evern "-PWRFLAG" will change to "f10.0". If you are in
symbol mode and you enter "F10.0", as soon as you enter that line,
the "F10.0" will change to "-PWRFLAG".

Note that you can use the Function keys in the editor to get into
the symbol table - rather than leaving the program to edit the
symbol table and then getting back into the program editor.

To edit a program block. Invoke the editor. Put cursor on line to be
edited. Softkey "edit". Make changes. "enter" - maybe three times.


DEALING WITH THE PROMMER (prom burner)
The Siemens PROM burner came with a software disk "STEP4/ST/PC-PAKET
1.00 ERW.EXT.PROMMER 1/1 as well as a small multilingual manual. The
manual contains instructions for installing the software. However,
it seems that our PC version of STEP5 contains the necessary
software. The prommer works without further software, and , in fact,
the software on the disk refuses to install.

As with the editor, the prompts and keystrokes for PROM operations
are not obvious. One invokes these functions from the main
STEP5 menu's "Management" submenu and "EPROMS" sub-submenu. This
takes you to a screen on which two parameters can be entered or
changed amd then entered. The top parameter should be left as
"WORD", which always the correct response for our S135 system.
The second parameter sets the checksum to "YES" or "NO". A YES must
cause the checksum to be generated and transferred to the PROM as a
data word. A NO probably results in a zero or some more unique
word to be written in the checksum loacation. When the EPROM is
read by the PLC, the PLC calculates the checksum of the incoming data
and compares it to the included checksum. If the included checsum
is "no check sum", the PLC can simply say ok, as if the checksum had
been valid. (Why would one ever turn off the checksum option?).

The other fields on this first PROMMER screen cannot be changed here;
they have been set earlier on page 1 and/or page2 of Settings. Afer
being sure that WORD is selected and checksum is YES, hit F6. All that
changes on the screen is the softkey description at the bottom.
When the "BLOW" function is selected, a screen appears asking for
two parameters. The first,B, is for block. Type A for all and hit enter.
The cursor moves to the PRT field (printer). Leave this field blank
if you don't want to print and exit by hitting the "Insert" key on the
PC. When you are prompted for PROGRAM NUMBER, type 500 if you are
dealing with a FLASH card. Enter the 500 by hitting the "Insert" key
or with a left mouse click. As is often the case, this is not enough;
you have to also hit Insert again , or maybe even 500 Insert Insert.
The lower light (yellow) on the PROMMER will first blink - probably
when the "500 Program" is being downloaded. It will light continuously
while the module is being DELETED (erased) or BURNED (programmed).

How to install the module in the PLC. Simply push the module into its
slot. Then clear the RAM by using STEP5 BLOCKS, DELETE, IN THE PLC,
ALL, OVERALL RESET. The delete erases the ram and the overall reset
causes the contents of the module to be loaded into the ram.

Manual procedure for reloading the RAM from the module. (Not as
foolproof as the STEP5 procedure described above). Suppose the module is installed and its
contents are present in the RAM.

Switch the top switch to the downward position, STOP.
Press the RESET button upward to RESET and hold it there for 5 seconds.
Press the RESET button downward to OVERALL RESET and hold it there.
Switch the RUN switch up and the down.
Release the lower switch.
Repeat the procedure at least once.


Manuyal procedure to erase the RAM:
Pull the module out of its socket. (As long as the module remains plugged
in, you cannot erase the RAM).

Clear the memory as follows:

Switch the top switch to the downward position, STOP.
Press the RESET button upward to RESET and hold it there for 5 seconds.
Press the RESET button downward to OVERALL RESET and hold it there.
After about 5 seconds, switch the RUN switch up.
After another 5 seconds, switch the RUN swith down.
After another 5 seconds, release the lower switch.


plc error: attempting to set or reset q0.0 when the digital output card is
not present results in an error
that stops the PLC. In this case a warm restart jumps past the error
and the (test) program finishes its 5-sec timeout and stops. Another
warm restart doesnt start it againl, since it has finished and is
awaiting a start via OB20 or OB21. Give it a regular cold start and
it encounters the error and immedately hangs again. Then another warm
start again pushes it past the error and lets the program run its
alloted course.

The lamp blinking program, when eventually successful, showed that
the digital output board must be plugged in at the time the PLC crate
is powered up (manuals do mention this) but that no external power
need be applied to the board (except to work the LEDs) and no DB1
need be written and entered.