Tektronix 4924 Tape Drive Emulator

[mmcgraw74]

I can't compile with Arduino 1.8.13 or 1.8.15 your original AR488_Store.  I get a message "arSerial was not declared in this scope"

My attempt at merging my code into AR488_Store is in AR488_Store-TLIST-FIND-OLD-CD-READ1-READf-HELP-TYPE folder.

What folder are your able to compile?

[WaveyDipole]

I can't compile with Arduino 1.8.13 or 1.8.15 your original AR488_Store.  I get a message "arSerial was not declared in this scope"

That's odd. I just downloaded it onto a computer other than my usual development machine and had no problem compiling for the Mega 2560 or Pololu 328PB. There were a handful of warnings, including a memory warning for the Pololu 328PB, but no errors. I did get an error when compiling for the Pololu 32u4 that prevented a successful compile although I didn't think we were using that board. Which board were you compiling for? Could you show me the actual output from the compiler please?

My attempt at merging my code into AR488_Store is in AR488_Store-TLIST-FIND-OLD-CD-READ1-READf-HELP-TYPE folder.

What folder are your able to compile?

I had a go at the 'AR488-644-TLIST-continuedDev' folder. Haven't tried the 'AR488_Store-TLIST-FIND-OLD-CD-READ1-READf-HELP-TYPE' yet. Will give it a go though.

[mmcgraw74]

I uploaded a new file into AR488_Store folder "compile errors on 8-June.tx".

I am using Arduino 1.8.15 on Windows 10 and compiled AR488_Store for my ATMEGA644 board, that compiles my AR488-644-TLIST-ContinuedDev without any errors.

arSerial looks like it is defined in AR488_Config.h in both my ContinuedDev folder and AR488_Store, but the Config.h in AR488_Store is 2KB larger.

[WaveyDipole]

Thank you. I have had a look at the compile errors file. You mention an ATMega644 board. I hadn't picked up on that from earlier posts or even from the names of the directories! I have not programmed or compiled for one of those previously so that may be the issue. It doesn't seem to appear on the list of AVR boards. I will check it out and report back. I may need to adjust the Config.h to include support for that board.

UPDATE: A little further digging suggests that the 644 (and 1284) are NOT supported by the Arduino IDE out of the box but I did find the following URL to add the board to the IDE:
https://raw.githubusercontent.com/Lauszus/Sanguino/master/package_lauszus_sanguino_index.json
Is this the one that you used?

UPDATE2: A quick test with that board shows it does produce the error you mention among other things because there is no section in Config_h that defines the serial port/device to use. I need to create a new section in the Config_h for it as well as a layout. Do you already have a pinout in mind?

[mmcgraw74]

The Panaduino 644-Narrow https://pandauino.com/en/644-narrow-1284-narrow-atmega644-atmega1284/ with Atmega644 CPU uses the MightyCore library: https://github.com/mrguen/644-1284-Narrow/blob/master/install/MightyCore-Pandauino.exe to add the Panaduino 644-Narrow and 1284-Narrow to Arduino.

This board is the smallest one I have found that has more I/O pins, and double the flash and RAM compared to the 32u4 AND the 5V pin compatibility for direct connection to drive GPIB.

I created my own Oshpark custom board to connect the 644-Narrow to the GPIB connector and Pololu MicroSD adapter with 3.3v level-shifter.

My custom pinout is in the AR488_Config.h file in my continuedDev folder:

Code: [Select]

/*******************************/
/***** AR488 CUSTOM LAYOUT *****/
/***** vvvvvvvvvvvvvvvvvvv *****/
#ifdef AR488_CUSTOM

// AR488_CUSTOM defs for Pandauino 644-Narrow plugged into artag's AR488 v3 GPIB connector PCB
#define DIO1  11   /* GPIB 1  */
#define DIO2  24   /* GPIB 2  */
#define DIO3  26   /* GPIB 3  */
#define DIO4  25   /* GPIB 4  */
#define DIO5  16   /* GPIB 13 */
#define DIO6  17   /* GPIB 14 */
#define DIO7  27   /* GPIB 15 */
#define DIO8  14   /* GPIB 16 */

#define IFC   12   /* GPIB 9  */
#define NDAC  3    /* GPIB 8  */
#define NRFD  2    /* GPIB 7  */
#define DAV   1    /* GPIB 6  */
#define EOI   0    /* GPIB 5  */

#define SRQ   15   /* GPIB 10 */
#define REN   13   /* GPIB 17 */
#define ATN   10   /* GPIB 11 */

#endif
/***** ^^^^^^^^^^^^^^^^^^^ *****/
/***** AR488 CUSTOM LAYOUT *****/
/*******************************/


This pinout for GPIB and microSD does not use the serial port TX/RX pins.

Here is the 644-Narrow pinout diagram.

Note ALL the PINs have Interrupt capability, although my sketch with custom layout does use the interrupts and had no issue interfacing to an HP data acquisition box using the 644-Narrow and my custom GPIB adapter as I previously posted in this thread.

[WaveyDipole]

The Panaduino 644-Narrow https://pandauino.com/en/644-narrow-1284-narrow-atmega644-atmega1284/ with Atmega644 CPU uses the MightyCore library: https://github.com/mrguen/644-1284-Narrow/blob/master/install/MightyCore-Pandauino.exe to add the Panaduino 644-Narrow and 1284-Narrow to Arduino.

Ok, will have a look at that.

This board is the smallest one I have found that has more I/O pins, and double the flash and RAM compared to the 32u4 AND the 5V pin compatibility for direct connection to drive GPIB.

Yes, makes sense.

My custom pinout is in the AR488_Config.h file in my continuedDev folder:

Code: [Select]

/*******************************/
/***** AR488 CUSTOM LAYOUT *****/
/***** vvvvvvvvvvvvvvvvvvv *****/
#ifdef AR488_CUSTOM

// AR488_CUSTOM defs for Pandauino 644-Narrow plugged into artag's AR488 v3 GPIB connector PCB
#define DIO1  11   /* GPIB 1  */
#define DIO2  24   /* GPIB 2  */
#define DIO3  26   /* GPIB 3  */
#define DIO4  25   /* GPIB 4  */
#define DIO5  16   /* GPIB 13 */
#define DIO6  17   /* GPIB 14 */
#define DIO7  27   /* GPIB 15 */
#define DIO8  14   /* GPIB 16 */

#define IFC   12   /* GPIB 9  */
#define NDAC  3    /* GPIB 8  */
#define NRFD  2    /* GPIB 7  */
#define DAV   1    /* GPIB 6  */
#define EOI   0    /* GPIB 5  */

#define SRQ   15   /* GPIB 10 */
#define REN   13   /* GPIB 17 */
#define ATN   10   /* GPIB 11 */

#endif
/***** ^^^^^^^^^^^^^^^^^^^ *****/
/***** AR488 CUSTOM LAYOUT *****/
/*******************************/



Sorry. Should have realized that, but thank you for the confirmation.

This pinout for GPIB and microSD does not use the serial port TX/RX pins.

That would explain the problem. The AR488 as it stands expects at least one serial port to be configured for communication with the PC. Are you intending to dispense with communication over serial/USB altogether? If so, then the references to the serial port, especially the verbose responses could be removed saving a bit of program memory. It also simplifies things considerably.

Here is the 644-Narrow pinout diagram.

Note ALL the PINs have Interrupt capability, although my sketch with custom layout does use the interrupts and had no issue interfacing to an HP data acquisition box using the 644-Narrow and my custom GPIB adapter as I previously posted in this thread.

(Attachment Link)

I noticed you had designed a new adapter board. Interrupts are not strictly necessary and I might be removing the feature from my next version. It doesn't seem to add anything really except complexity.

[mmcgraw74]

I am using serial now for development, but the 'production' 4924 tape emulator will not need a serial interface, just the GPIB with primary and secondary addressing.

The firmware can be updated over USB, and the SD files can be updated by plugging the microSD card into a PC.

[mmcgraw74]

I have been putting my serial messages into the EEPROM with the F( ) formatting to keep them out of the flash.  These messages won't be needed over GPIB.

[WaveyDipole]

The Panaduino 644-Narrow https://pandauino.com/en/644-narrow-1284-narrow-atmega644-atmega1284/ with Atmega644 CPU uses the MightyCore library: https://github.com/mrguen/644-1284-Narrow/blob/master/install/MightyCore-Pandauino.exe to add the Panaduino 644-Narrow and 1284-Narrow to Arduino.

I generally don't use Windows but I found further information in mrguen's manual for the Panduio. He refers to MCUdude's MightyCore toolkit:

https://github.com/MCUdude/MightyCore#how-to-install

The instructions there provide the JSON URL to add to the Additional Boards Manager URL's box in Preferences in the IDE which is:

https://mcudude.github.io/MightyCore/package_MCUdude_MightyCore_index.json

So now I have the same board toolkit installed in Boards Manager.

I am using serial now for development, but the 'production' 4924 tape emulator will not need a serial interface, just the GPIB with primary and secondary addressing.

The firmware can be updated over USB, and the SD files can be updated by plugging the microSD card into a PC.

Ok, so that is understood. There will be no need to communicate over serial in "normal" operation. The CH340 USB/UART chip still connects to TX0/RX0 for uploading the firmware, but we are not going to use it for communication over USB. I presume that configuration (e.g. GPIB address) will be set in firmware or via the Config file? There might be enough pins to add an 8-way DIL switch, although of course, the adapter board is already designed and purchased, so perhaps can we skip that idea.

I have been putting my serial messages into the EEPROM with the F( ) formatting to keep them out of the flash.  These messages won't be needed over GPIB.

A good idea, always. Flash gets used up pretty quick otherwise.

Funny how all of the Panduino graphics deliberately hide the details of the chips on the board!  Yet, they are obvious and easy enough to find: either a 644 or a 1284 MCU and a CH340 UART so not sure what the big secret is!

I will have a think about how to address the serial port (error) problem and revise the AR488_Store code accordingly. Incidentally, I don't mind removing the AR488 tag from it altogether if it suits.

[mmcgraw74]

No need for adjustable GPIB device address, I would just hardcode address 5 in the config file.

There is a full schematic for the Pandauino board in the user manual and both page 1 and 2 are in the github doc folder:
https://github.com/mrguen/644-1284-Narrow/blob/master/doc/Narrow%20v1.0%20schematics%20-%201.jpg

[WaveyDipole]

Been studying the sketches and trying to catch up a bit.

Just a question: the version you have in the 'AR488-644-TLIST-continuedDev.ino' directory adds you routines into the main command list, i.e. so that they are called with ++find, ++cd, ++readf etc. Is it the intention to call these commands using Prologix format, or is this for test purposes?

I did wonder whether the intention might be to eventually port these functions to the code that responds to remote commands over GPIB, but I also notice that you have defined a couple of ArduinoStream objects which also point to Serial ports. Unless this is all for test purposes, it does appear that we do require an active serial port? I just want to clarify and establish which bit of code (directory) I need to work with?

It seems developing Tek storage functions at your end is coming on apace. I need to catch up but I want to make sure that I am heading in the right direction....

If you want, I can also add the //------------- separators to my parts of the code. They do make individual functions and sections of code stand out a bit better.

[mmcgraw74]

all my ++ commands are for test. 

I imagined that the routines will directly map to GPIB secondary addresses, and the ArduinoOutStream cout(Serial) would change to ArduinoOutStream cout(GPIB)?

For example if the 4924 emulator primary address is 5 we have a good start on the blue highlighted secondary address commands with my serial commands: tlist, find, old, cd, read1

These commands are the minimum to run most of the hundreds of Tektronix 4050 programs I have recovered.  The ones that write to files would wait for the WRITE routine to be written.  The MARK command is only used to create new file(s), which wouldn't be hard to code with SdFat.

[ Specified attachment is not available ]

[WaveyDipole]

Ok, that begins to make sense. So for my part, I need to get the Store part working so that the routines can be dropped in and tested. To that end I have ordered a 1284 chip to help along with development. I already have a development board knocking around with an AtMega16 plugged in, but that has half the memory of a Uno//Nano/32u4, so far too little to be useful. The 644 and 1284 are both pin compatible so should just drop into the same board.

How are you going to get the SD Card formatted? I started work on some ++ commands to do that and manage the file system, swap "tapes" etc, but if we are not using the serial port then all ++ commands will be null and void from now on so any configuration will either have to be hard coded or made available in Config.h which is quite easy to do. This also means that a blank SD card will either need to be pre-formatted before insertion into the reader, or automatically formatted when the script is first run with it inserted. Of course, if the card is already formatted, that will need to be detected so as not to not format it again. I made some progress along those lines by automatically creating a directory for the tapes. I will have to familiarise myself with the current arrangement and adapt accordingly.

I will start work on getting the store part to compile then on the 644/1284 and hopefully have something ready and available to test once the chip arrives.

I am currently on something called a Low Fodmap Diet on doctors orders and feel quite poorly, but I will do my best to get things moving.

[mmcgraw74]

My plan for getting the data files on the microSD card is to tell the user to format the card as FAT32, then unzip the file that will contain all the program and data files into the proper directories.

I will be creating that zip file from my github archive, and will edit all the file commands to add @5: which will then cause BASIC to access the tape emulator at primary address 6.  BASIC will add the secondary address number based on the command name when the tape emulator is being addressed.

The tape emulator will only respond to commands to its primary address 5, and the secondary address will map directly into my routine for that command.  Ex GPIB primary address 5, secondary address 19 is the TLIST command and the code will return the list of files in the current microSD card directory.

[mmcgraw74]

If you are ordering a 1284 board,are you also ordering a Pololu microSD with 3.3V regulator https://www.pololu.com/product/2587?

You should be able to connect the Pololu microSD to the 1284 board with a breadboard and jumper wires.

I can send you one of my 4924 Tape Emulator boards with a GPIB connector already soldered on, but you would need a Tektronix computer to test it with GPIB.  I know someone in the UK with a working Tektronix 4052 that could be interested in helping test the tape emulator.

[WaveyDipole]

I already have a MicroSD card reader here. Its not Pololu branded, but so shouldn't need to order one. It just hooks up to the SPI connector (MOSI, MISO, CLK) and has the neccessary 3.3V regulator and level shifter onboard. For project purposes  plan to connect it with Duupont jumper wires as you suggest.

One of your emulator boards might be useful as that will make it easier for me to connect up to the GPIB bus, which would otherwise require 16+ jumper wires.

I can probably emulate some commands at a basic level by using a terminal and a test fixture script but that is probably all I can hope to achieve without owning a Tek 4052. There are also a couple of simulators available which may be worth trying out. At this stage its not too important but I would like to be able to test at least at some rudimentary level the responses to primary/secondary addressing over GPIB.

BTW, I think that perhaps we might remove the BlueTooth unit for now? Also, thinking about it, if the config will be hard coded (in the Config.h file) then do we really need to use EEPROM? I don't know whether you plan to support it, but I think it would be best to remove all unnecessary code.

[mmcgraw74]

I agree with removing Bluetooth support as the Pandauino boards have no network capability.

Yes, any microSD adapter with 5V to 3.3V level shifters should work fine.

Here is my Tektronix 4924 Tape Emulator adapter board schematic.

I used the same connector as on artag's AR-488 board, but removed the mounting holes from the GPIB connector model, and created a 644-Narrow model and microSD connector model.

[mmcgraw74]

Schematic wasn't very readable - I posted the schematic and gerber PCB files on AR488-Store.

[WaveyDipole]

Thank you. The image shows the 328PB version but I presume there is now a 644 version?

I will remove Bluetooth as well as Verbose mode since if there is to be no serial comms then that will be superfluous. I have moved GPIB interface parameter configuration to Config.h so am now going to start removing ++ commands that set interface parameters.

[mmcgraw74]

I'm not sure what 328PB image you are referring to - here is a better photo of my Tektronix 4924 Tape Emulator with the ATMEGA644PA CPU on the 644-Narrow Pandauino board, Pololu MicroSD adapter and GPIB connector:

[WaveyDipole]

Sorry, it seems I got mixed up with the files and looked at an older version of the emulator. Thank you for the drawing and the photo. Both will be very helpful and should help me wire it up properly.

[WaveyDipole]

My custom pinout is in the AR488_Config.h file in my continuedDev folder:

Code: [Select]

/*******************************/
/***** AR488 CUSTOM LAYOUT *****/
/***** vvvvvvvvvvvvvvvvvvv *****/
#ifdef AR488_CUSTOM

// AR488_CUSTOM defs for Pandauino 644-Narrow plugged into artag's AR488 v3 GPIB connector PCB
#define DIO1  11   /* GPIB 1  */
#define DIO2  24   /* GPIB 2  */
#define DIO3  26   /* GPIB 3  */
#define DIO4  25   /* GPIB 4  */
#define DIO5  16   /* GPIB 13 */
#define DIO6  17   /* GPIB 14 */
#define DIO7  27   /* GPIB 15 */
#define DIO8  14   /* GPIB 16 */

#define IFC   12   /* GPIB 9  */
#define NDAC  3    /* GPIB 8  */
#define NRFD  2    /* GPIB 7  */
#define DAV   1    /* GPIB 6  */
#define EOI   0    /* GPIB 5  */

#define SRQ   15   /* GPIB 10 */
#define REN   13   /* GPIB 17 */
#define ATN   10   /* GPIB 11 */

#endif
/***** ^^^^^^^^^^^^^^^^^^^ *****/
/***** AR488 CUSTOM LAYOUT *****/
/*******************************/


This pinout for GPIB and microSD does not use the serial port TX/RX pins.

Here is the 644-Narrow pinout diagram.

Note ALL the PINs have Interrupt capability, although my sketch with custom layout does use the interrupts and had no issue interfacing to an HP data acquisition box using the 644-Narrow and my custom GPIB adapter as I previously posted in this thread.

(Attachment Link)

Monty, I am struggling to reconcile the layout definition above with the attached circuit diagram as the connected pin numbers seem different? I had assumed that pin numbers/names on the inside of the 644-Narrow box represented the pin markings on the Panduino Narrow board, but I don't see A0-A7 so I am guessing these are referred to as pins 24-31?. I can only presume that since you successfully connected up and were able to communicate with your HP data acquisition box, that the definition above is the one to follow but could you please clarify?

[mmcgraw74]

I received my PCB order from Oshpark yesterday and assembled one of the boards - it worked with EZ-GPIB to access my Agilent 34970A Data Acquisition Unit!



Here is the Tape Emulator plugged into the Agilent for testing with EZ-GPIB:



The assembly is only about 0.1" taller and 0.1" wider than artag's AR488 design with a Pro Micro.

The 644-Narrow board with the ATmega644 processor is quite a bit longer than the Pro Micro, so there are no mounting holes for the GPIB connector, but I plan to modify the 3D case design posted recently in the AR488 thread, which mechanically supports both the GPIB connector and the stack of boards without using the GPIB mounting holes.

Here is the new custom layout for my Tape Emulator PCB:

Code: [Select]

/*******************************/
/***** AR488 CUSTOM LAYOUT *****/
/***** vvvvvvvvvvvvvvvvvvv *****/
#ifdef AR488_CUSTOM

// AR488_CUSTOM defs for Pandauino 644-Narrow in Monty's Tektronix 4924 Tape Emulator PCB connector
#define DIO1  10   /* GPIB 1  */
#define DIO2  11   /* GPIB 2  */
#define DIO3  12   /* GPIB 3  */
#define DIO4  13   /* GPIB 4  */
#define DIO5  14   /* GPIB 13 */
#define DIO6  15   /* GPIB 14 */
#define DIO7  16   /* GPIB 15 */
#define DIO8  17   /* GPIB 16 */

#define IFC   22   /* GPIB 9  */
#define NDAC  21   /* GPIB 8  */
#define NRFD  20   /* GPIB 7  */
#define DAV   19   /* GPIB 6  */
#define EOI   18   /* GPIB 5  */

#define SRQ   23   /* GPIB 10 */
#define REN   24   /* GPIB 17 */
#define ATN   31   /* GPIB 11 */

#endif
/***** ^^^^^^^^^^^^^^^^^^^ *****/
/***** AR488 CUSTOM LAYOUT *****/
/*******************************/


WaveyDipole,

You are correct, thanks for finding my error - the pinout above in my post from April 9 is the correct pinout with my new Tektronix 4924 Emulator PCB. 

I got a replacement laptop in early May, reinstalled Arduino and picked an earlier file with the AR-488 PCB to continue work on the emulator.  I didn't do any more live GPIB testing with EZGPIB or I would have caught my mistake.

I have updated all the config.h files on AR488-Store master except for your main AR488-Store files.

The new custom pinout matches the schematic I posted for the new PCB and this view of the gerber files for my new Tektronix 4924 Emulator PCB with Panaduino 644-Narrow, GPIB connector and Pololu microSD adapter pinouts:




I have attached the Pandauino pinout diagram again.  Yes, the Pandauino Arduino pins are all numbers in my config.h file, although I'll bet the Port names could also be used.  Note the +5V and GND at the bottom of the pinout diagram are on the ISCP header, not the corner pins of the Pandauino!

[WaveyDipole]

That's great and very helpful. Thanks.

The 1284 IC arrived yesterday and I am hoping to give it a test today. In the meantime, your adapter is showing as being at 'Sorting Centre, Chicago, Cook County, Illinois, United States' as of the 16th June. No update for today yet, but its evidently on its way. In the meantime, I will hopefully be able to hook it up with some Dupont wires to the breadboard.

[mmcgraw74]

Since the Pandauino board includes the ISCP header installed, I found the easiest way to solder the ISCP header pins to my GPIB adapter was to remove the plastic spacer from the ISCP header and heat one ISCP pin at a time from the top of the board and push it down a bit.  You only want the ISCP pins to barely penetrate the GPIB adapter PCB to make it easier to get the soldering iron under the GPIB connector.

The three photos in this post are closeup views of the ISCP to GPIB connections.
You also need a tall header to connect the Pololu MicroSD adapter to the GPIB adapter PCB.

I put the ISCP plastic spacer back on top of the now shorter pins - the pins may need to be trimmed slightly so they won't touch the microSD adapter PCB.  The ISCP plastic spacer now gives a little mechanical support to the overhanging microSD adapter PCB.

I also trimmed the rest of the Pandauino board pins after soldering them to the GPIB adapter PCB to prevent them touching the metal shell of the GPIB connector.