Subject: Bode Plotter (Good One)


		Bode Plotter for the HP48sx


	The following is an ASC-> encoded program to display bode
plots on an HP48SX. Download the program, press ASC->, then
type 'BODE' STO. Directions are included below.


	      INSTRUCTIONS FOR BODE PLOTTER
	First download and install the bode plot routines from
the earlier posting. Enter the BODE directory. You sould
see [BODED] [MAG] [ANG] [SMOO] in the first 4 menu entries.
An example has been preloaded so just press [MAG] to see
the magnitude plot for the tranfer function:
	    H(s)=[50*(s*(1+s/10))]/[(1+s/10^4)*(1+s/10^7)]
Once the plot has completed use the arrow keys to move the
cursor around the screen. You can press [COORD] to get the
cursor coordinates. The X-coordinate is the frequency (rad/s)
in decades (e.g. x=1.5 => 10^1.5 rad/s). Tick marks are every
decade. The Y-coordinate is in decibels (e.g. y=20 => 20 dB).
Tick marks are every 20 dB. Now press [ON] to return to the
menu. Next press [ANG] to see the angle bode plot. The X-
coordinate is once again the frequency (rad/s)in decades (e.g.
x=1.5 => 10^1.5 rad/s). Tick marks are every decade. The Y-
coordinate is in degrees (e.g. y=20 => 20 degrees). Tick marks
are every 20 degrees. Press [ON] to return to the menu.

Now we will step through an example from the beginning.
Press [BODED]. A temporary menu is created and the calculator
is halted. The menu should now look like this:
[S] [EQN] [BD] [ED] [PPD] [CONT]
and if you press [NXT] you should see [ABORT]. You will now
enter the tranfer function:
      100*s/[(1+s/10)*(1+s/10^4)*(1+s/(2*10^4))]
Next store it into EQN (left shift [EQN]). After that specify a
beginning decade (0 left shift [BD]), ending decade (7 left shift
[ED]), and the points per decade (7 left shift [PPD]). The higher
PPD is, the longer the calculator will take, but a more accurate
plot will result. Now press [CONT]. If you had wished to cancel
the plot you could have pressed [NXT] [ABORT]. You will have to
wait for approx. 90 seconds for the calculator to finish its
computations. Once it is done you will hear 2 short beeps if BEEP
is enabled. As before press [MAG] to view the magnitude plot of a
band-pass filter and [ANG] to produce the angle plot. If you ever
press [ANG] and the plot is split in two (due the value returned
by the ARG function), then press [SMOO] to smooth out the plot and
press [ANG] again. Do not use [SMOO] unless the plot is split
otherwise the angle values taken from the plot will be incorrect.

CREDITS:
The bode plot routines were written entirely by Thedore W. Gregg and
are copyright 1991, EXCEPT for the SPLOT and GETC routines (originally
LPLOT and GETC) which were written first by Paul Dale and modified for
use in these programs. You have my permission to freely distribute and
use these routines for any non-profit or non-published purpose.

FOLLOWING IS PAUL DALE'S DISCLAIMER FOR LPLOT AND GETC:
------------------------------------------------------------------
As usual, this program is copyright myself, 1991 all rights
reserved but as usual, any non-profit usage of this program is ok
by me (if you want to include it in your commercial software or
publish it in a book/journal then you require my permission first
--- it is usually given).

Enjoy...
	Pauli                                                            seeya

Paul Dale               | Internet/CSnet:grue@batserver.cs.uq.oz.au
Dept of Computer Science| Bitnet:grue%batserver.cs.uq.oz.au@uunet.uu.net
Uni of Qld              | JANET:grue%batserver.cs.uq.oz.au@uk.ac.ukc
Australia, 4072         | EAN:grue@batserver.cs.uq.oz
			| UUCP:uunet!munnari!batserver.cs.uq.oz!grue
f4e6g4Qh4++             | JUNET:grue@batserver.cs.uq.oz.au
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DISCLAIMER:
These routines are provided "as is" with no expressed or implied
warrantees. Any damage or losses caused by the use of these programs
is soley the resposibility of the user.


If you find these programs useful or have questions please drop me a
note. If you can think of any way to speed them up please do so.

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\ Theodore W. Gregg        | The most endangered species- the honest man, /
\ MACC-Operations          | Will still survive annihilation.             /
\ 1210 W. Dayton St.       | Forming a world state of integrity,          /
\ Madison, WI 53715        | Sensistive, open, and strong.                /
\ gregg@macc.wisc.edu      |                                   (N. Peart) /
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