Using script studercomm.pl.


 


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Monitor
Tape deck monitor

Here you find some information on using the Perl script studercomm.pl and configuration file studercomm.conf. To communicate with the tape recorder you need a list with available commands for your recorder. For a 2 channel recorder you find such a list here, the list for the multichannel models A820 and A827 is here.

Software installation.

To use the script you need a Perl interpreter version 5.10 or later. From a DOS-prompt you can check if Perl is already installed with perl -v. If it isn't installed, you can download Perl from the Perl website.
Similar for Linux/UNIX user, start a terminal and enter perl -v. If it is not there, see your distribution set or go to the Perl website.
Addtionally you need 2 Perl modules (for Windows: 1). For Linux/UNIX you need the Perl modules Term::ReadKey en Device::SerialPort. See your distribution set or else download the modules from CPAN. For Windows you need one addtional module, Win32::SerialPort (that goes for 64-bits Windows too). You can download it at CPAN too. Installation from CPAN requires administrator or root rights and some knowledge of make and install procedures. More on that here and here.

The Perl script.

Mei 2018: Versie 2 is ready. Various problems with flow control (xon/xoff) and local echo fixed. Thanks to Jacob Korn for his contributions. Jacob connects analogue synthesizers to computers via MIDI. Recommended for musicians.

There are two versions. One version for Linux, UNIX ans OSX (with LF line ends) and a version for Windows (with CR/LF line ends). Right click the link and choose Save to download. For Linux, UNIX, OS X:

For Windows (32 and 64 bits):

After download the files should reside in the same directory. You can start the script from a command prompt with perl studercomm.pl.

Configuration file studercomm.conf.

When Perl and the modules are there you have to enter the serial port you are using to connect to the tape recorder. Open file studercomm.conf with a suitable editor. Lines beginning with '#' are comments, these lines will be ignored. There should be one line beginning with 'Commport=' with the correct serial port. For Windows this could be Commport=COM3.
Once you entered the serial port you can save the file and start communications. The other options in this configuration file will suit most users.

Options Baudrate, Data bits, Stopbit and Parity are RS-232 protocol settings. The values here, 9600,8,1,none, conform to the standard used by most tape recorderes. If you changed these settings in your tape recorder you need to change this line accordingly.

Option CapsOn is used in terminal mode. This converts all lowercase characters to uppercase before sending them to the tape recorder.

With option ReadDelay the speed of data transfer can be changed. Applying a lower delay value (in milliseconds) here will speed up data transfer between computer and tape deck. Too low a value can lead to errors. Value 100 (milliseconds) is the standard. This turned out to be reliable at baudrate 9600.

Monitordelay is like 'Readdelay', but only works during the monitor function. This has to do with the amount of data the tape deck sends. Value 160 (milliseconds) is standard here.

With option Pidfile a different file name for .pid file (process id) can be specified (only for Linux, BSD and OS/X).

Option DebugFile specifies a file name for a debug file. If you remove the '#' sign in front of it, each run of the script will produce a text file named 'studercomm.dbg' containing all data transfers during that run. Useful in case of errors.

Start the Perl script.

The recommended way to run is from the command prompt. Only then you will get to see all the messages from the script. Once you know which commands you need, you can integrate them with a shortcut.

From Windows: Select Start, Run and enter cmd.exe . Then change to to the folder where studercomm.pl and studercomm.conf reside. Start the Perl script: perl studercomm.pl

For Linux, FreeBSD and OSX: Open a terminal and navigate to the directory. containing studercomm. Run the script with perl studercomm.pl You can make studercomm.pl executable. You will have to set the execute bit with chmod +x studercomm.pl for that to work. Additionally, you have to make sure that the first line in the script points to your Perl interpreter. You can find the path to Perl with whereis perl After that you can start the script like this: studercomm.pl

At program start the script tries to establish a connection using the specified serial port. If successful, the script will ask the tape recorder for its type and for a serial number or software date. After that the processing begins. Machine type and serial number (A810) or software date are used in the names of all output files. The serial number consists of 6 digits, the software date consists of a week number and a year like this: 001689 for week 16 in 1989. Output file names look like this:

  tttt-nnnnnn-logicalname-yyyymmdduumm.txt
Here, tttt denotes the machine type (e.g. A807), nnnnnn. represents the serial number or software date.

Command line options.

Running the script without command line options like perl studercomm.pl will produce two output files. The first named report is a human-readable text file containing all audio settings. You can find an example here. The second file is named restore. This text file contains all the commands needed to write the audio settings back to the tape recorder. You can find an example here.
During the process you may notice that the script changes the speed and equalization setting on the tape deck in order to read the actual settings. You can restore the file with audio settings with command line option -b (see below).

Some models and software versions do not provide means for the script to change tape sort, speed and/or equalization in order to read the settings. them. On these machines, notably C27n and A810, only the settings for the currently selected tape sort, speed and equalization will be read. In order to get a list of parameters for the other tape sort, speeds and equalization, change the setting on the tape deck first. Then restart studercomm to read the settings again.
Without command line arguments, the script does not write parameters to the recorder.

Option -a.
Using perl studercomm.pl -a the audio settings associated with the currently active settings (tape sort, tape speed and CCIR/NAB) will be written to a file named current-set . Each line contains a command (SAP) to write a setting back to the tape recorder. It is in fact a backup file for the currently active setting state, you can restore it using the -b option. Here is an example of such a file.
Using option -a the script will not write audio parameters to the recorder.

Option -b <input file>
With option -b the specified input file will be read and transmitted to the tape recorder line by line. Empty lines and lines beginning with '#' will be ignored. Each line must contain one single command. With this option, the files current-set and restore can be send to the tape recorder for a partial or complete restore of audio settings. If the file name contains spaces the name must be put between quotes.
Please note: If you use this option for a partial restore (which is always the case with current-set and sometimes with restore) you will have to switch your tape deck to the settings that were selected at the time the file was made. Otherwise, you might overwrite the audio settings for speed 15ips with the settings for 7.5ips.
Using this option carefully, audio settings will be overwritten.

Option -c <recorder-command> [ <input file | >output file ]
Option -c allows you to send a single command to the tape recorder. For commands requiring files the file name can be specified, for both input and output. A few examples.

  perl studercomm.pl -c PLY
  perl studercomm.pl -c FWD
  perl studercomm.pl -c STP
  perl studercomm.pl -c TM?
The first line sends command PLY to the tape recorder. It has the effect of pressing the PLAY-button. You might like to try the STP command after this. The fourth example asks for the timer reading, which will then appear on screen. You can capture the answer from the tape deck in a file like this:
  perl studercomm.pl -c "D 108 26E >ram-108-26e.txt"
Command D 108 26E asks for the contents of RAM from address 108 hex with. length 26e hex. The result will be a memory map, it will be written to file ram-108-26e.txt. This command contains spaces, hence the quotes. Command 'D ...' does not work on all models/software versions. A similar command is 'P'. Command P writes output in Motorola exorciser record format, also known as .s19 or .srec.:
  perl studercomm.pl -c "P 108 227 >ram-108-227.txt"
In this example the output is send to file ram-108-227.txt. Two more examples with files:
  perl studercomm.pl -c "SPA >backup-td-au.bin"
  perl studercomm.pl -c "LPA <backup-td-au.bin"
Command SPA (save parameters, for A812, A816 and A820 only) saves all settings from the tape recorder. In this example, the data will be written to file 'backup-td-au.bin' This produces a complete backup file. Using command LPA (load parameters) with the same file as input can give you a full restore. Other models and software versions may respond to similar commands 'S' and 'L', see your manual. Using option -c you can write almost anything to the tape recorder. Use it with care.

Option -h
This will simply show all available options for studercomm.pl.

Option -m
Monitor your tape deck. With this option studercomm uses command 'DST' to show a running view on the status of your tape deck. See the screencapture on the right. Linux, OSX and BSD will allow you to send PLAY, STOP, FWD, RWD, LOC and REC commands with a single keypress from within this view. With Windows, only the running status is shown, since Windows doesn't provide a mechanism to intercept a keypress while continuously reading the serial port.

You may have to experiment with the value for 'Monitordelay' in studercomm.conf for this function to run smoothly. It depends on the speed of your computer. Value 160 (milliseconds) should run with older hardware. A lower value runs faster and will react faster to keystrokes. Too low a value will lead to incomplete output or no output at all.

Option -t
This option starts the terminal mode. You can enter commands here and instantly see the answer from the tape deck. It allows you to control the tape deck using commands like PLY, RWD, FWD, REC and STP (play, rewind, fast forward, record and stop).
You can leave this terminal with quit, exit or bye.

An everyday example.

Let's assume we need to use an A810 to make a recording that will be played on a 4-track Revox B77. The record level of a 2-track A810 is usually far too high for a 4-track B77. So we will have to lower the record level of the A810 around 40%. First we put the A810 in the right mode, say 7.5ips and NAB. Then we read the actual audio parameters like this:

  perl studercomm.pl -a
File A810-123456-current-set-201912081130.txt will be made. In that file we find this:
  # Channel 1 & 2, 4=record level, hex value.
  SAP 1,4,8C
  SAP 2,4,8C
The recording level at 7.5ips and NAB for both channels is set at hexadecimal value 8C. We have to lower that by 40%. Yes you can! To do that we start the terminal mode:
  perl studercomm.pl -t

  Studercomm: Initializing port /dev/cuau3 to 9600,8,1,none... Okay
  Revox A810 found

  Studercomm, terminal mode: Type QUIT, EXIT or BYE to terminate.

  >hex 8c
  HEX 8C equals decimal number 140
  >dec 84
  DEC 84 equals hexadecimal number 54
  >SAP 1,4,54
  >SAP 2,4,54
  >
Command 'hex 8c' calculates hex value 8c to decimal value 140. Lower this 40 percent, that makes 84. Command 'dec 84' calculates decimal value 84 to the hexadecimal equivalent 54. So we then write that value for both channels to the tape deck with the SAP-commands. We're ready to start recording now.

Once the recording has finished the record level of the A810 A810 should be reset to its original state. We can use the file we made earlier.

  perl studercomm.pl -b A810-123456-current-set-201912081130.txt

Error messages and possible causes.

Other error messages are possible. If you get such an error please feel free to mail me. You will find my mail address on the right. Include a description of the problem and add a debugfile (see configuration options) if possible.
 




Last update 8 december 2019.