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*** ACNET DOCUMENTATION *** ------------------- 1. INTRODUCTION ------------ ACNET provides steady state analysis of electronic circuits containing any combination of resistors, capacitors, inductors, mutual inductors, op-amps, transistors (bipolar & FET) and transformers. The output shows the gain, phase shift, input and output impedances of the network at any given frequency and also provides a gain plot over a wide frequency range. The circuit values are stored on disk. These may be modified at any time, extra components and nodes can be added or deleted, and input and output nodes redefined. The program can be used to calculate the performance of any linear circuit, such as audio, video, i.f. and r.f. amplifiers, active and passive filters, matching networks, etc. It can be used to evaluate the effectiveness of decoupling components and the stability criteria of oscillators. Simple but comprehensive graph plotting facilities are also included, suitable for any text printer. Better quality is available for EPSON (both 9 & 24 pin), IBM and HP DeskJet printers. Sixty predefined frequency scales extending up to 300MHz over a range of 1, 2 or 3 decades are provided together with the facility for user defined frequency scales over any range. ACNET is easy to use with menus and helplines provided. Default settings are automatically set - these may be changed by the user. It is easy to install from a supplied batch file and can be set up to run from two floppies if a hard disk is not available. Circuit examples are provided, including simple filters, a delay line, a feedback amplifier, TV IF amplifier, a gyrator, a mutually coupled tuned circuit, a Baxandall audio tone control and a 9 band graphic equalizer. 2. FILES PROVIDED -------------- Your supplied disk contains 25 files :- READ_ME.TXT ............ This documentation INSTALL3.BAT ............ Installation program for Version 3.2 G_PRINT.BAT ............ Print program for 24 pin and HP printers ACNET.EXE ............ Executable ACNET_X.EXE ............ Extended executable ACNET.DEF ............ Defaults file CIRCUITS.TXT ............ Circuit schematics HPFILTER.DAT } FB_AMP_2.DAT } TVIFAMP3.DAT } DUBTUNE.DAT } BANDPASS.DAT } GYRATOR.DAT } .......... Sample datafiles for use with ACNET NOTCH300.DAT } BAX_3.DAT } WHITE_PK.DAT } LINE.DAT } GRAPH_EQ.DAT } GRAPHS.TXT ........... Sample graphfiles using only printable chars GRAPHS.GRF ........... Sample graphfiles in ASCII with ESC codes GRAPHS.ELX ........... Sample graphfiles for EPSON LX 9 pin printers GRAPHS.EFX ........... Sample graphfiles for EPSON FX 9 pin printers GRAPHS.IBM ........... Sample graphfiles for IBM printers GRAPHS.E24 ........... Sample graphfiles for EPSON 24 pin printers GRAPHS.HPK ........... Sample graphfiles for Hewlett Packard printers 3. INSTALLATION ------------ The supplied files should be copied to your working disk - preferably a hard disk. The installation program INSTALL3.BAT will do this for you, creating the appropriate directories - \NET_V3 for the main files, and subdirectories \DATFILES and \GRFFILES for the data and graphfiles. To install ACNET on drive C (for example), place a copy of the supplied disk in your input drive and set this as the current drive. Then type :- INSTALL3 C: Any other valid drive may be designated for the programs. Files created under previous versions are compatible with Version 3 after modification - this is carried out automatically by this new version of ACNET and so existing datafiles you have already may be transferred to the new directory and used. Operation using two drives, one for the main programs and the other for data and graphfiles is covered later. 4. VERSIONS AVAILABLE ------------------ Two versions of the program are supplied - ACNET.EXE and an extended version ACNET_X.EXE. They are identical to the user and differ only in accuracy and speed. ACNET is a software only version adequate for most purposes. ACNET_X provides higher precision and is consequently slower. However, if you have a coprocessor fitted to your machine this will automatically be used by the extended version giving about the same speed as the normal version. So if a coprocessor is available, always use the extended version ACNET_X. Without a coprocessor use ACNET for speed, especially for graph plotting. However, if you are using a very wide range of circuit values you may find that some results, (most especially the input impedance), are somewhat inaccurate due to matrix rounding errors. If you suspect this then check at a few spot frequencies using ACNET_X. Also it has been found that loading EMM386.EXE slows down the operation of the extended version if a coprocessor is not present. The programs supplied by the shareware vendors are limited to a maximum of 9 nodes when calculating the circuit response. You may obtain the full 50 node versions by registering with the author - see Section 11. 5. RUNNING ACNET ------------- To run, set the default directory to \NET_V3 and type ACNET or ACNET_X for the extended version. The screen (which is set for 80*25 characters) will show the program and system parameters and for ACNET_X confirmation of a coprocessor if one is present on the machine. All future references to ACNET will apply to both versions unless otherwise stated. At the prompt press <ANYKEY> to continue. Component details are stored in datafiles with a .DAT extension. The names of those already available will be displayed. The last used datafile will be shown in reverse video and this datafile may be selected by just typing <ENTER>. The default settings as supplied will select the file HPFILTER for you when you first start. This datafile contains values for a simple three element high pass passive filter (see CIRCUITS.TXT) and I suggest you use this initially to work through the menu options before defining your own circuits. Alternatively, select any other datafile by means of the up/down/left/right arrow keys or select the 'NEW FILE' option to create a new datafile (described later). Having selected an existing datafile, its current revision number and a short message will be displayed at the top of the screen. 6. THE MENU OPTIONS ---------------- Having opened a datafile the main menu will be displayed - select the option required either by using the keyboard up/down arrows and then <ENTER> or by typing the first letter on the menu line (included for compatibility with Version 1). Note that throughout the program, options that require a single character do not require a line terminator. Typing ahead does not cause any problems as the input buffer is always cleared immediately prior to selection. An obvious yes/no choice requires a <Y> for 'yes', any other character or just <ENTER> for 'no'. When you have a multiple choice to make after the main menu, the options available will be displayed at the bottom of the screen. The program name, revision, name of datafile in use and the date will always be displayed at the top of the screen. All the default settings are taken from the defaults file ACNET.DEF and the values as supplied will suit most applications. <D> - Display Component Values ------------------------------ This starts by showing the number of nodes defined and the input, output and common node numbers. Then all components, their allocated node numbers together with values and any further parameters will be displayed in an ordered sequence on the screen. The display will pause if the data exceeds the screen length and also at the end of the file - <ANYKEY> will enable you to continue and will finally return you to the main menu. Note that the last digit for capacitor values represents 0.1pF and for inductors 0.1uH. <P> - Print Component Values ---------------------------- The circuit values etc. will be printed via LPT1: in the same format as appeared on the screen above. If the printer is off line, the program will automatically return to the main menu. To terminate printing, press <ESC> to return to the main menu. <R> - Calculate Response of Circuit ----------------------------------- Supply the required frequency value (in Hz) - the response of the circuit at that frequency will then be calculated and displayed showing :- (1) Gain in decibels (dB). A loss is indicated by a negative value. (2) Phase Shift between defined input and output nodes in degrees. Note that the displayed phase values are only continuous in the range +180 to -180 degrees. (3) Modulus of Input Impedance in Ohms. (4) Modulus of Output Impedance in Ohms. If the real part of either impedance is negative this will be indicated. Repeat for other frequencies as required. To obtain a printout, use the <PRINT SCREEN> key. Any non-numeric key and/or <ENTER> will return you to the main menu. N.B. ACNET will calculate the response of a circuit at zero frequency provided there is a DC path between the input and output - otherwise a runtime error will occur. E.g., NOTCH300 has a finite response at zero frequency whereas HPFILTER does not. <C> - To Change Component Values -------------------------------- To input or to change existing component values the format is as follows :- COMPONENT SYMBOL PARAMETERS --------- ------ ---------- RESISTOR R Node_1 Node_2 Resistor Value(Ohms) CAPACITOR C Node_1 Node_2 Capacitance Value(uF) INDUCTOR L Node_1 Node_2 Inductor Value(mH) Series R(Ohms) MUTUAL INDUCTOR M Pri_S Pri_F Sec_S Sec_F Lp(mH) Ls(mH) k Rp(Ohms) Rs(Ohms) TRANSFORMER T Pri_S Pri_F Sec_S Sec_F Ratio (1:n) BIPOLAR B Base_node Coll_node Emitter_node Beta Ic(mA) TRANSISTOR Ft(MHz) Cbc(pF) Cbe(pF) Cce(pF) FET F Gate_node Drain_node Source_node Gm(mA/V) Cgd(pF) Cgs(pF) Cds(pF) OP-AMP A I/P+ I/P- O/P Gain(dB) Zin(MOhms) f3dB(MHz) [Op-amp common is circuit common node] Values are typed in at the * prompt. E.g., a capacitor of value 6.8uF and a resistor of 3300 Ohms connected in parallel between nodes 3 & 4 would be input as :- * C 3 4 6.8<ENTER> * R 3 4 3300<ENTER> Definition of the series resistance of both inductors and mutual inductors (Rp, Rs) is optional - if undefined by the user then a value of 1.0E-15 Ohms will be assumed. Similarly for transistor capacitances which will be set to 1pF, Ft to 300MHz and for op-amps the default gain would be 80dB, the input resistance 10MOhms and the cut off frequency (-3dB) would be set to 10MHz. Components in datafiles generated by earlier versions of ACNET where these optional values could not be defined will automatically have them set to the above default values. They can easily be changed. So a bipolar transistor with base connected to node 4, collector to node 7, emitter to node 9, with a current gain (Beta) of 200 and a collector current of 1.5 mA would be input as :- * B 4 7 9 200 1.5<ENTER> The interelectrode capacitances would automatically be set to 1pF and Ft to 300MHz. However, if you wished to specify an Ft of 150MHz and capacitances of Cbc = 0.5pF, Cbe = 3.0pF and Cce = 10pF for the transistor then this would be input as :- * B 4 7 9 200 1.5 150 0.5 3.0 10<ENTER> Components can be typed in any order. If any component value already exists its value will be changed to the latest value but you cannot put components of the same type in parallel. Note that the delimiters must be spaces and the symbol must immediately follow the * prompt. The nodes for two terminal networks may be given in either order. Typing incorrect data will be indicated by a response of 'TYPING ERROR' and no change will take place. To delete a particular component type the symbol, the node numbers and then <D>. E.g., to delete the above bipolar transistor you would type :- * B 4 7 9 D<ENTER> Do not set main component values to zero otherwise errors may occur. If you wish to join two nodes together without reorganising node numbers, then use a small value resistor - say 0.1 Ohm. On entering the 'Change Mode', the datafile revision number is automatically updated - this will appear on the graph and component printouts. Having input/changed/deleted the values required, type <G> to go on. If the datafile is a new one, you will be prompted to define the input, output and common nodes. If an existing file was used then you may redefine these nodes if you wish. This allows you to calculate the response of any intermediate part of a circuit - you may, for example, choose a decoupling arm as the input node in order to ascertain its effectiveness. Note that the maximum node number is 50 (9 for the smaller versions of the program) with no restriction on the number of components. You cannot have an input/output/common node number greater than the highest component node number defined. If you ever have less than 3 nodes ACNET cannot calculate a result. <O> - Open a New Datafile ------------------------- The current datafile will be closed and another can be opened. Either an existing file may be chosen or a new one created following the same procedure as described previously in Section 5. Defining a New Circuit & Datafile --------------------------------- If you are starting with a new circuit, you must number all the nodes (junctions) starting at 1 as shown in the example circuits. It does not matter how you organize the numbers, but there should be no gaps in the sequence. If you subsequently change the circuit and delete all connections to a node you must either reorganize the following node numbers or you can leave the node unconnected - this will just slow down the analysis. All common (ground) connections must have the same node number. The power supply connections count as common, although you can allow for the power supply source impedance. Having done this you must then create a new datafile either immediately on running ACNET or from the 'Open File' menu option. Select 'NEW FILE' and type the name of the new file required. (Note that the .DAT extension will be taken by default - even if you supply a different file extension). If you give an illegal filename you will be prompted for another. The new file will be created for you and you will then be prompted to supply an appropriate header message of up to 45 characters which will be displayed when you subsequently access the datafile. The revision no. of a new file will be set to 0. You must subsequently enter the 'Change Mode' in order to define the circuit values. <G> - To Plot a Graph --------------------- On selecting the graphplot facility, five separate menus will be available on the screen giving a choice from 60 preset frequency scales or a user defined scale. Select the one you require by using the up/down/left/right keys. You have a choice of frequency range as indicated, covering from 0.003Hz up to 300MHz, over 1, 1.5, 2 or 3 decades and utilizing 80 or 132 columns. Having made your selection of frequency scale, press <ENTER> to continue. If you selected the user defined scale then you will first have to supply the start and finish frequencies required - on subsequent use of this scale new values may be defined or the previous frequency values can be reselected by just pressing <ENTER>. Naturally the finish frequency must be greater than the start frequency. Once the graph plot calculation has been initiated, progress will be indicated by a count, 5-79 or 5-131. You may abort and return to the main menu at any time by typing <ESC> ; there may be some delay with large circuits. Having completed the calculations, the screen will show the frequency range employed, the maximum and minimum amplitude values computed over the frequency range selected as well as the current graph parameters. You may optimize the graph plot parameters to best fit the range of the response to be plotted. These parameters are :- 1) Graph Scale Default initially 20dB. Should be set to 4, 8, 12, 20, ----------- 40, 60 or 80dB (or any value divisible by 4). These values represent the approx. length of 40 printed lines. 2) Top of Graph Default initially +5dB. May be set within limits +200 to ------------ -200dB. It is best to use multiples of 5 or 10. 3) No. of Lines Default initially 45 lines. May be set in range 1 to 86. ------------ 4) Superimpose Mode You may superimpose plots, but results can be slightly ---------------- confusing if graphs converge on the simpler two level plots. If the Superimpose facility is enabled, you may clear the plot array at any time. The array is cleared automatically if you change plot parameters or if you enter the 'Set Defaults' mode. 5) Enhanced Mode If enabled, graphplots are printed in emphasized and/or ------------- double print as defined by the default values. This facility is not available if the printer mode has been set to 0 or both DOUBLE and EMPHASIZED are OFF. It is not operational for HP printers. Defaults for the above are taken from the default file settings every time you open a datafile. Having set up the plotting parameters, you can still change these before proceeding if you wish. On continuing, the response will be displayed on the screen. You can examine all the plot area by using the arrow keys and also Pgup/Pgdn and Home/End in the usual way. <ESC> will allow you to continue and you can then elect to print the graph if you wish. The graph data will be stored in the subdirectory \GRFFILES using the data filename or a revised filename of your own choice. Whichever you choose, the graphfile will have the extension .TXT or .GRF or .ELX or .EFX or .IBM or .E24 or .HPK as determined by the PRINT MODE setting which you set as appropriate for your printer. You cannot change the extension when renaming the file and the default on initial startup will be .TXT. (For a description of the PRINT MODE settings see the 'Set Defaults' option below). Finally, the full name and size of the graphfile will be displayed. Note that you cannot rename a file to itself, and if you use the data filename, subsequent graphfiles will always overwrite the previous graphfile. If you wish to have a revised plot with an alternative amplitude scale using the values already calculated, then there is provision to do this. Also, if the printer was off-line you may come back to print out in this way too. All of this should be obvious from the screen prompts. Finally use <ESC> to return to the main menu. You may then plot other graphs using an alternative frequency range or you may make component changes and plot more graphs using the Superimpose mode too if you wish - but obviously you cannot change either the frequency scale or the amplitude scale in any way if you are wishing to superimpose plots. N.B. Typing <ENTER> or an illegal character (e.g., a letter when a number is required) for any of the graphplot options will cause the default or the previously defined value to be used. If you type an incorrect numeric value, this will not be accepted and you will be prompted for another value. Also, if there are less than 3 nodes defined for the circuit the program will not run and you will be returned to the main menu. Graph Types and Printing from DOS --------------------------------- Graphs are plotted using the characters .': in Print Modes 0 and 1, and with multilevel dots in Print Modes 9,10,23,24 and 50 which are designed for use with IBM, EPSON and HP printers. These latter versions give vastly improved quality and should be used if you have the appropriate printer. As mentioned above, when you exit ACNET the last graph generated will also be found in \GRFFILES in datafilename .TXT .GRF .ELX .EFX .IBM .E24 or .HPK (depending on the Print Mode chosen) or in a file with your own designated name and with the appropriate extension. The .TXT .GRF .ELX and .EFX graphs may then be printed using the DOS PRINT command. The .IBM .E24 and .HPK variants are modified by PRINT. This can be avoided by using the TYPE command with redirection to the printer, which is already provided in G_PRINT.BAT. For example from \NET_V3 you would use :- PRINT GRFFILES\HPFILTER.GRF PRINT GRFFILES\GRAPHS.ELX TYPE GRFFILES\HPFILTER.E24 > LPT1: ... or G_PRINT HPFILTER.E24 G_PRINT GRAPHS.HPK Note that G_PRINT automatically adds the path to these graph files. The graph points are calculated using an accurate logarithmic frequency scale, the values being exact at 0.3, 3, 30, 300Hz ... etc. The remainder of the frequency intervals indicated on the graphs may have a small error due to the integer printing grid. The frequency range code is shown at the bottom of the graph preceded by '$' and followed by the graph file extension. The 132 column plots give a better representation as the natural slope of 20dB/decade (and multiples thereof) produce straight lines, there being 40 frequency intervals per decade at this setting. <S> - Set Defaults ------------------ The default settings for the last datafile used, the graph parameters, graph length, printer settings and the disk drive for data and graphfile storage are contained in the file ACNET.DEF. This is read every time you open a datafile. You may change most of these default values yourself. The set values will be shown in brackets and will not be changed if you just press <ENTER>. The default parameters are :- F_CODE - Frequency range code used on entering the graphplot routine. Values appear on menus and graphplots. Possible range 0 - 60. SCALE - Graph scale setting used on entering the graphplot routine. May be set to 4, 8, 12, 20, 40, 60 or 80dB. TOP - Top of graph scale used on entering the graphplot routine. May be set to any value from -200 to +200dB. NO_LINES - Number of lines used for the plot on entering the graphplot routine. May be set to any value from 1 to 86. PRINT MODE - May be set to 0, 1, 9, 10, 23, 24 or 50. These settings give the following graph output :- 0 : Two level plots using printable characters only. This will work on any standard text printer but you set the printer into condensed mode and appropriate line spacings yourself. Graphfiles produced with this setting have a .TXT extension. 1 : As above with the addition of EPSON control codes to give improved line spacing, enlarged and underlined print as well as condensed and enhanced print if enabled. For use with older EPSON printers which cannot handle redefined characters. Graphfiles have a .GRF extension. 9 : Plots using four levels/character for use on 9 pin EPSON standard printers including the LX range. Graphfiles have a .ELX extension. 10 : Plots using four levels/character for use on 9 pin FX EPSON printers. Graphfiles have a .EFX extension. 23 : Plots using eight levels/character for use on 24 pin IBM printers. Graphfiles have a .IBM extension. 24 : Plots using eight levels/character for use on 24 pin EPSON standard printers. Graphfiles have a .E24 extension. 50 : Plots using eight levels/character for use on Hewlett Packard DeskJet 500 printers. Graphfiles have a .HPK extension. CONDENSED - May be ON or OFF. Used only with 132 column plots. Note that some printers cannot print in CONDENSED mode if DOUBLE or EMPHASIZED print is enabled. For HP printers 16.7 cpi is always used with 132 column output. EMPHASIZED - Gives better quality print when ENHANCED is ON. DOUBLE - Gives better quality print when ENHANCED is ON. Neither DOUBLE or EMPHASIZED operational with HP printers. DRIVE_2 - Designated second drive for data and graphfiles. As installed only one drive is used as indicated by the symbol '\' . The ability to designate a second drive enables users with only low capacity floppy drives to use two drives, as one disk will soon become full when using ACNET. By keeping the main program files on one drive and the data and graphfiles on the second, much more space may be used - in fact any number of disks can be used in the second drive for data and graphfiles. To use two drives, first install ACNET onto one drive (say A:) using INSTALL3.BAT as already described and take the opportunity to become familiar with its operation. (If your drives have only 360K capacity then you will have to limit the number of files transferred and store the sample graphfiles on another disk). Then use the 'Set Defaults' option to set DRIVE_2 to (say) B: to use this for data and graphfile storage (any drive A-Z may be used). The new directories will be generated on the second disk automatically. You will have to move any existing datafiles to the second drive yourself. Operation is much slower when using two floppy drives in this way. Do not delete the datafile directory \DATFILES set up by the main installation program as without this directory ACNET cannot start from the original default file settings. To restore operation to the original single drive reset the DRIVE_2 parameter to '\' . The same defaults file is employed whichever version of ACNET is used. If the defaults file becomes corrupted or even deleted, a new one with the original default values will automatically be regenerated. <H> - Help ---------- Displays this documentation. Use Up/Down, PgUp/PgDn and Home/End keys as before and <ESC> to quit. <Q> - Quit ---------- This will close the current datafile and return you to DOS. N.B. In the unlikely event of not being able to return to the main menu, try <CTRL><C> and <CTRL><BREAK> to return to DOS ; if this fails then you will have to reboot. Do not attempt this while the disk is being accessed in case datafiles become corrupted. 7. SAMPLE DATAFILES ---------------- Ten example datafiles are included in your package. Schematics are given in CIRCUITS.TXT and typical graphplots for these in GRAPHS.TXT/.GRF/.ELX/.EFX/ .IBM/.E24 and .HPK - print out the appropriate graphplots to see what can be done. Four of the circuits contain more than 9 nodes and so the response of these can only be computed with the 50 node version of ACNET. (1) HPFILTER.DAT is a simple three element high pass filter with a cut off frequency (-3dB) of 299Hz. The default graphplot settings suit this circuit well. Use the Superimpose mode and change R 1 2 from 0.2 Ohm to 1.0 and then 5.0 Ohms and note the changes in the response (as shown in the first graph example). Note that with Version 3 the inductor and its series resistance can be combined into one component. (2) FB_AMP_2.DAT is a simple two stage feedback amplifer with a gain of 30dB. Frequency response is 3dB down at 78Hz and 17,200Hz. You can determine the feedback factor by opening the loop and noting the increase in gain. The power supply impedance is also included (10 Ohms & 1000uF). (3) TVIFAMP3.DAT is a 3 transistor TV IF amplifier with traps for sound and chroma sub-carriers, used by Number One Systems Ltd. in their advertisements for their circuit analysis software. ACNET gives results in good agreement with their published figures as can be seen from the graphplot supplied. This is a good example of where a user defined frequency scale is needed as the amplifier covers such a restricted frequency range. (4) DUBTUNE.DAT is a mutually coupled double tuned circuit as would be employed in an i.f. amplifer. The response with coupling factors (k) ranging from 0.04 (overcoupled) to 0.0033 (undercoupled) are shown. A coupling factor of 0.0157 gives critical coupling - maximum bandwidth with a flat response. (5) BANDPASS.DAT is a simple Butterworth active filter centred on 12MHz. The circuit is taken from Electronics & Wireless World Dec 90, p1061. (6) GYRATOR.DAT is a negative resistance filter employing a gyrator - from Electronics & Wireless World, Dec 89, p.1203. Note the notch of over 50dB at a frequency of 2770.5Hz. Varying R 3 12 will change the shape of the response. (7) NOTCH300.DAT is a high Q circuit tuned accurately to 300.0Hz. Note a loss of 158dB at the resonant frequency. (8) BAX_3.DAT is a Baxandall tone control circuit popular in audio amplifers. The bass response is controlled by the potentiometer formed by R 15 16 & R 16 17 and the treble by R 10 11 & R 11 12. To vary the response change the ratio of the resistors keeping the sum constant at 100k and 25kOhms respectively. The example graphplots show the response with the tone controls in various positions - the Superimpose mode was used to obtain these plots. (9) WHITE_PK.DAT is a filter to convert white noise to pink noise. It has a slope approximating to -3dB/octave over the range 10Hz to 40kHz. The circuit is taken from the Maplin magazine Electronics No.61 p53. The author claims an accuracy of 0.25dB over the frequency range ! (10) LINE.DAT is a distributed LC line of 47 T sections with C=200pF & L=2uH correctly terminated with its characteristic impedance Zo of 100 Ohms. Total delay is 0.94uS giving 360 degrees phase shift at 1.063MHz. The input impedance Zin is always 100 Ohms at any frequency up to about 15MHz. Zout is a function of frequency as the driving end of the line is not matched. Zout is zero at low frequencies but at 265,950Hz, where the line is a quarter of a wavelength long, the phase shift is 90 deg. and Zout reaches its first maximum. It is interesting to evaluate the line parameters at half, three quarters and unity wavelength. (Above about 15MHz the simple equations for Zo and the delay are no longer valid due to the finite number of sections). This circuit has the maximum of 50 nodes. On an 12MHz 286 (without coprocessor) the program takes 23 sec (real version) and 115 sec (extended version) for each frequency calculation. A 33MHz 486 takes under 3 sec for both the real and extended versions. It is primarily the number of nodes - not the number of components - that determines the time taken. (11) GRAPH_EQ.DAT is a nine band audio graphic equalizer taken from the NSC Audio/Radio Handbook 1980. 8.1. MAIN CHANGES INCORPORATED IN VERSION 2 -------------------------------------- 1) Easy to use menus provided, with no type ahead errors and improved error handling. 2) Smaller stack used for ACNET.EXE, thus reducing the memory requirements for this version. 3) Graph plotting facilities considerably extended with the provision of 60 preset frequency scales and a user defined frequency scale. Also the graphplot parameters can be set after computation has been completed and the response is displayed on the screen before being printed. Plotting scales can be revised without repeating the calculations. 4) Provision of a defaults file which can be changed by the user. The last used datafile can be opened by default on restarting the program. 5) The ability to use two drives if required, one for the main program and the other for the storage of data and graphfiles. 8.2. MAIN CHANGES INCORPORATED IN VERSION 3 -------------------------------------- 1) Easier datafile selection from the screen. 2) The use of predefined symbols for graph plotting - this gives vastly improved graph quality on EPSON compatible printers, both 9 and 24 pin. 3) 30% speed improvement when processing large arrays. 4) Addition of mutual inductance circuit elements. 5) Improved models for transistors and op-amps incorporating frequency dependent parameters. 6) Inductors may be defined with a series resistance without designating a separate node. 8.3. MAIN CHANGES INCORPORATED IN VERSION 3.2 ---------------------------------------- 1) Printing capabilities extended to include IBM Proprinter, EPSON FX and HP DeskJet printers. 2) Graph files reduced in size by removing redundant spaces. 3) All screen displays now provided by ACNET - no need to use LIST.COM. 4) Change in address for registration. 9. FAULTS AND RUNTIME ERRORS ------------------------- ACNET is written in Borland Turbo Pascal V 6.0. Full error checking is on all the time as this does not slow the program down appreciably. Common errors (most of which occur if you choose inappropriate parameters) are :- 002 : File not found. 003 : Path not found. 005 : File access denied. 100 : Disk read error. 101 : Disk write error. 150 : Disk is write protected. 160 : Device write fault. 200 : Division by zero. 201 : Value out of range. 205 : Floating point overflow (less likely to occur in extended version). 207 : Invalid floating point operation (incl. 8087 stack overflow). Comprehensive testing has been carried out on a range of IBM compatible PCs running DOS 3.3 & DOS 5.0. The graphplot routines have been tested on an HP DeskJet 500 printer, on EPSON LX400 and TEXAN/KAGA KP-810 printers for the 9 pin plots and on EPSON LQ400 and STAR LC24/10 for the 24 pin variants. The STAR was also used to emulate the IBM Proprinter X24. If your EPSON printer does not support the redefined character standard (up to and including ESC/P83) you will probably get one of the characters ;<=>?@ABC etc. in each plot position. If this is so you will have to use PRINT MODE 0 or 1 (or obtain a better printer !). Note that printers may need revised DIP switch settings to enable redefined characters to be used and that some so called "EPSON compatible" printers do not comply fully with the EPSON standard. 10. FUTURE DEVELOPMENT ------------------ Version 4.0 of the program is due to be completed next year. It is planned to have :- 1) The ability to input complex Y parameters for components. 2) Component values can be entered using suffixes k,M,u,p,n etc. 3) Files with predefined semiconductor parameters which can be imported into datafiles. 4) Colour will be used to enhance displays. Your suggestions for any other additions/improvements would be welcome. 11. REGISTRATION ------------ This program was written by - Peter M. Montgomery Address - Downings Bells Hill Stoke Poges Telephone - 0753 643384 SLOUGH SL2 4EG (England) ACNET is issued as shareware. Advice, subsequent revisions and copies of the full program which can handle larger circuits with up to 50 nodes can be obtained by registering with the author for a fee of 10 pounds sterling (plus 2 pounds for postage if overseas). When registering it would be helpful if you would indicate (i) the Version of ACNET you are currently using and (ii) your source of supply. The results from the graphplotting routine can also be made available as a file if you wish to use your own plotting package. ACNET : Version 3.2 Copyright (C) 1991/93/94 P.M. Montgomery -------------------------------------------------------------- READ_ME.TXT 2/1/94