project: extending HP3478A functionality

[kirill_ka]

What I meant was buttons to select your functions but I guess SRQ must be a hard press, does it?

Yes, a kind of. If the 3478ext works in a pass through mode (GPIB adapter), it can't control the bus on it's own. For example, the continuity mode doesn't allow sending any other commands to the instrument. Otherwise it will start to skip events. So the only way that could be done is to add some special commands to interact with the "extended features".

[lmester]

Before program exit I send the following commands:

"D1"      'Turn instrument LCD display on
"++auto 0"   'Tell instrument to stop talking
"T1"      'Instrument trigger normal on stop
"++loc"      'instrument to local mode

I have now added "++exit".

This will return an "Unrecognized command" from the real Prologix adapter but won't cause any problems.

Please test it and verify that it's working with your firmware.

It works for me, thanks!

Now it would be nice to add Kirill's extended function to your software. 

It's good to know that ++exit is working.

It looks to me that using the kirill extended functions is a choice of one or the other. My software needs to have control of the instrument's GPIB bus. Kirill's 3478ext also needs this.

The primary purpose of my program is to allow a Windows PC to control the instrument and do extended data logging. I'm certainly not going to try and convert and add 3K+ lines of C to my program!

If kirill needs me to do anything during my GPIB adapter detection, I'd have no problem adding this. Do you need anything to get our programs to work better together? Does your firmware respond to ++ver? If you can provide a unique substring in response to ++ver, I could make adjustements based on the presence of your firmware.

[Mp3]

Hmm, something didn’t go right for me on this...

I had the issue where the pins of the GPIB socket were too narrow for arduino style pin headers. I soldered pin header cables to the underside of the socket instead.

I used the two avrdude commands on the github documentation to program the hex file and set the fuses with my USB-TTL on Linux.

Both times the arduino responds fine to commands from the computer before I switch the HP on, but when I do the arduino seems to die even though it lights up at power on.

I have tried with both usb power on one and power from the HP on the other.

I have another arduino pro board left but I wanted to ask before I Brick that one too. Is the issue my usb-ttl programmer? I only have a usb ttl and a ST-Link at my disposal.
I’m worried the fuse settings didn’t program and the boards are fried.
I’ve triple checked my wiring so I don’t think it’s that...

[kirill_ka]

I’m worried the fuse settings didn’t program and the boards are fried.

You can't program the fuse bits with the serial interface at all. And the fuse settings are not that critical.
But I wonder where the VCC wire does go?

[Mp3]

I’m worried the fuse settings didn’t program and the boards are fried.

You can't program the fuse bits with the serial interface at all. And the fuse settings are not that critical.
But I wonder where the VCC wire does go?

There is a nearby spot marked +5, i measured it with the 3478a powered on, so i attached a diode to that point and that is what the internal vcc was coming from. I only tried that after the inital run with USB power also ended up with a non responsive arduino.

I forgot to mention - i accidentally mixed up the colors of the wires when making one with the diode attached. so i'm certain it's going to 5v and ground properly, although the colors are backwards from what they should be . I apologize for that.

I've tried to reprogram the hex and eeprom to both arduinos i tried so far, but no luck as neither responds. Does it sound like they are bricked?

I tried replicating the button presses of the demo video, so i'm not quite sure what i did wrong, but i assume the ardunio pro is getting fried from some of the GPIB wiring as it had the same reaction with usb power,

[kirill_ka]

I think it's more likely a power supply issue. May be ether wrong polarity or high voltage.
The GPIB pins should be current limited according to the spec.
Did you check the actual voltage going to the arduino board?

[Mp3]

I think it's more likely a power supply issue. May be ether wrong polarity or high voltage.
The GPIB pins should be current limited according to the spec.
Did you check the actual voltage going to the arduino board?

yes - but not the current, seemed okay (4.5v off my little diode wire, or 5.0 off usb)

thanks for your help, by the way, i appreciate it. excited to figure it out 

[kirill_ka]

I just noticed that you're messing around the place where the line voltages and the transformer primary side exposed...

[Mp3]

I just noticed that you're messing around the place where the line voltages and the transformer primary side exposed...

that is why i had each row of soldered-on wires insulated with a layer of kapton tape on each side. The photo was more to show that i didnt do awful soldering. You can't tell from the picture, but tehy're long enough to bring the board far out of the line voltage zone.

[kirill_ka]

>

The GPIB pins should be current limited according to the spec.

It looks like I'm wrong.
I didn't find the current limiting requirement for the driver in the GPIB spec. It only
specifies the minimum current: "High state: Output voltage (three-state) ≥ + 2.4 V at −5.2 mA". The maximum spec is up to the driver IC.
However if you power the atmega from the same 5V as the driver chip, I don't know how the data lines could be the problem.
However, 4.5V supply seems a bit low. I suggest you use a Schottky diode.

[Mp3]

3rd try is the charm =)

Turns out my  3478A was on channel 6, not 23 - and on the 3rd Arduino I programmed the EEPROM as well as the hex file. I don't know if one or both steps were necessary. I assume so because my old Arduino's aren't responding to serial.

All's well, tried a few GPIB commands and looks good =)

If you wanna do a bottom side install like me, I suggest using only angle header pins on the Arduino board so that you can wrap it up in electrical tape after it's all wired up, then it can fit with the bottom panel still on. I left header cables for the USB-TTL attached so that I can plug one in when I need it.

[kirill_ka]

3rd try is the charm =)

Turns out my  3478A was on channel 6, not 23 - and on the 3rd Arduino I programmed the EEPROM as well as the hex file. I don't know if one or both steps were necessary. I assume so because my old Arduino's aren't responding to serial.

All's well, tried a few GPIB commands and looks good =)

Congratulations, you passed the quest  It makes me think I should start a Q&A section.

However those GPIB address and EEPROM issues do not explain what happened to the first couple of arduino boards?
Are they alive?

[Miti]

I tripped over that GPIB Address 23 as well but I forgot about it. It is somewhere in this trail

[Mp3]

3rd try is the charm =)

Turns out my  3478A was on channel 6, not 23 - and on the 3rd Arduino I programmed the EEPROM as well as the hex file. I don't know if one or both steps were necessary. I assume so because my old Arduino's aren't responding to serial.

All's well, tried a few GPIB commands and looks good =)

Congratulations, you passed the quest  It makes me think I should start a Q&A section.

However those GPIB address and EEPROM issues do not explain what happened to the first couple of arduino boards?
Are they alive?

It's a mystery to me as well wit the first two boards, to be honest. I didn't try to make a serial connection to see if they responded before plugging them in, I have tried minimal testing with those two boards and have not been able to get them to respond whatsoever. I get programmer not responding errors with them. I may try to shock some life back into them at another time.  i could also send them in a plain envelope to you if you wish to inspect them! postage would be like less than $10 to you for this and if it helps you in any way, i don't mind.

If they're of no use, no worries, if i can't revive them i will toss them.

By the way, doing two failed attempted installs for the bottom side gave me some good ideas on how to build an Arduino pro really slim with angle headers only. I ended up moving the +5V diode wire over to the 5V point right next to the ground wire in my above picture and get 4.95v off it so I am happy.

I was thinking, with long enough ribbon wire, you might be able to sneak the USB TTL connection wires out around the HPIB address dip switches. There seems to be plenty of room around it.

Oh - i almost forgot, the only other difference is that the two times it didn't work, I had the GPIB header from the back panel unplugged. This time , i plugged it back into its socket. I don't see why that should matter.

I tripped over that GPIB Address 23 as well but I forgot about it. It is somewhere in this trail

Yes, thank you; it's your post that made me realize I had to check that!  You deserve credit for sure 

[kirill_ka]

It's a mystery to me as well wit the first two boards, to be honest. I didn't try to make a serial connection to see if they responded before plugging them in, I have tried minimal testing with those two boards and have not been able to get them to respond whatsoever. I get programmer not responding errors with them. I may try to shock some life back into them at another time.  i could also send them in a plain envelope to you if you wish to inspect them! postage would be like less than $10 to you for this and if it helps you in any way, i don't mind.

Not sure if it would help me, but I'm curious I'll pm you the address. I'd post the investigation results here if I get them.

[yo0]

3rd try is the charm =)

Turns out my  3478A was on channel 6, not 23 - and on the 3rd Arduino I programmed the EEPROM as well as the hex file. I don't know if one or both steps were necessary. I assume so because my old Arduino's aren't responding to serial.

All's well, tried a few GPIB commands and looks good =)

Congratulations, you passed the quest  It makes me think I should start a Q&A section.

However those GPIB address and EEPROM issues do not explain what happened to the first couple of arduino boards?
Are they alive?

It's a mystery to me as well wit the first two boards, to be honest. I didn't try to make a serial connection to see if they responded before plugging them in, I have tried minimal testing with those two boards and have not been able to get them to respond whatsoever. I get programmer not responding errors with them. I may try to shock some life back into them at another time.  i could also send them in a plain envelope to you if you wish to inspect them! postage would be like less than $10 to you for this and if it helps you in any way, i don't mind.

If they're of no use, no worries, if i can't revive them i will toss them.

By the way, doing two failed attempted installs for the bottom side gave me some good ideas on how to build an Arduino pro really slim with angle headers only. I ended up moving the +5V diode wire over to the 5V point right next to the ground wire in my above picture and get 4.95v off it so I am happy.

I was thinking, with long enough ribbon wire, you might be able to sneak the USB TTL connection wires out around the HPIB address dip switches. There seems to be plenty of room around it.

Oh - i almost forgot, the only other difference is that the two times it didn't work, I had the GPIB header from the back panel unplugged. This time , i plugged it back into its socket. I don't see why that should matter.

I tripped over that GPIB Address 23 as well but I forgot about it. It is somewhere in this trail

Yes, thank you; it's your post that made me realize I had to check that!  You deserve credit for sure 

@Mp3

Glad you do it, can you post pictures of your finished installation please?


Best regards.

Pio

[Mp3]

@Mp3

Glad you do it, can you post pictures of your finished installation please?


Best regards.

Pio

Hey Pio,

Sure, this is my first install though. I have a 2nd (nicer, and calibrated) 3478A I still need to do the mod on, and I'll probably make it a little nicer this time. Though, by the time i got to my last attempt at this one it was much less of a mess than the first two 

Some of my thoughts for anyone considering the internal install:

• You will be working in the area where there is line voltage active even with the power off, so do a really good job of making sure the wires you solder will never come loose.
• Open the bottom up and plan to get the Arduino well out of the way of the line voltage area under the plastic cover, so make your wires long enough ( I did not make them long enough to re-install the plastic line voltage warning plate so I went crazy with the Kapton tape)
• The solder for the HPIB pins and the pins themselves don't seem to solder very easily. The solder balls up easily. Just be patient with it and maybe wick some of it up
• Use right angle pin headers for the entire Arduino if you have any hope of getting the bottom panel back on
• I can't prove it, but it might need connections on the top side to work properly, since the two installs I had that didn't work had the HPIB header by the transformer unplugged, and the one that worked had it plugged in. Also, Miti's successful install was a top side install and I think kirill_ka's internal  installs are top side as well.
• You can sneak a 5-wire ribbon cable for the USB-TTL out through the HPIB ID DIP switch assembly as there's plenty of room for it to come out of the case.
• There are several options for powering it, I chose to pull 5V from one of the marked test points with a 1n4148.

[yo0]

@Mp3

Glad you do it, can you post pictures of your finished installation please?


Best regards.

Pio

Hey Pio,

Sure, this is my first install though. I have a 2nd (nicer, and calibrated) 3478A I still need to do the mod on, and I'll probably make it a little nicer this time. Though, by the time i got to my last attempt at this one it was much less of a mess than the first two 

Some of my thoughts for anyone considering the internal install:

• You will be working in the area where there is line voltage active even with the power off, so do a really good job of making sure the wires you solder will never come loose.
• Open the bottom up and plan to get the Arduino well out of the way of the line voltage area under the plastic cover, so make your wires long enough ( I did not make them long enough to re-install the plastic line voltage warning plate so I went crazy with the Kapton tape)
• The solder for the HPIB pins and the pins themselves don't seem to solder very easily. The solder balls up easily. Just be patient with it and maybe wick some of it up
• Use right angle pin headers for the entire Arduino if you have any hope of getting the bottom panel back on
• I can't prove it, but it might need connections on the top side to work properly, since the two installs I had that didn't work had the HPIB header by the transformer unplugged, and the one that worked had it plugged in. Also, Miti's successful install was a top side install and I think kirill_ka's internal  installs are top side as well.
• You can sneak a 5-wire ribbon cable for the USB-TTL out through the HPIB ID DIP switch assembly as there's plenty of room for it to come out of the case.
• There are several options for powering it, I chose to pull 5V from one of the marked test points with a 1n4148.

thank you very much, looks very good. i think a slim case would be very neat and can isolate the arduino against the main board.

what you think? i think there is enough height room between the bottom side of the pcb and the case.

best regards.

Pio

[Mp3]

thank you very much, looks very good. i think a slim case would be very neat and can isolate the arduino against the main board.

what you think? i think there is enough height room between the bottom side of the pcb and the case.

best regards.

Pio

Hmm, that looks small enough to fit, you could probably make it work

edit: Maybe the case would fit with some double sided  tape in the empty area where the thick ground trace separates the two sides? Not 100% sure but seems like it?

[yo0]

thank you very much, looks very good. i think a slim case would be very neat and can isolate the arduino against the main board.

what you think? i think there is enough height room between the bottom side of the pcb and the case.

best regards.

Pio

Hmm, that looks small enough to fit, you could probably make it work

edit: Maybe the case would fit with some double sided  tape in the empty area where the thick ground trace separates the two sides? Not 100% sure but seems like it?

yes i think it will fit there.

best regards.

Pio

[kirill_ka]

It's a mystery to me as well wit the first two boards, to be honest. I didn't try to make a serial connection to see if they responded before plugging them in, I have tried minimal testing with those two boards and have not been able to get them to respond whatsoever. I get programmer not responding errors with them. I may try to shock some life back into them at another time.  i could also send them in a plain envelope to you if you wish to inspect them! postage would be like less than $10 to you for this and if it helps you in any way, i don't mind.

Not sure if it would help me, but I'm curious I'll pm you the address. I'd post the investigation results here if I get them.

Mp3, I've got the boards. I'm afraid there isn't a lot of mystery there.
One board (with all the pins soldered) is working. I've no problem programming it with both ISP and bootloader interfaces. So I can't tell what was wrong with it. The other one has a solder dag shorting out the resonator.
Thanks for the boards, they always come in handy!

[Mp3]

It's a mystery to me as well wit the first two boards, to be honest. I didn't try to make a serial connection to see if they responded before plugging them in, I have tried minimal testing with those two boards and have not been able to get them to respond whatsoever. I get programmer not responding errors with them. I may try to shock some life back into them at another time.  i could also send them in a plain envelope to you if you wish to inspect them! postage would be like less than $10 to you for this and if it helps you in any way, i don't mind.

Not sure if it would help me, but I'm curious I'll pm you the address. I'd post the investigation results here if I get them.

Mp3, I've got the boards. I'm afraid there isn't a lot of mystery there.
One board (with all the pins soldered) is working. I've no problem programming it with both ISP and bootloader interfaces. So I can't tell what was wrong with it. The other one has a solder dag shorting out the resonator.
Thanks for the boards, they always come in handy!

I'll chalk it up to user error on the alive board, then. How embarrassing though on the other board 

No problem, would love to know if you find any quirks from doing a bottom side install. Glad they made it to you safely!

[PixieDust]

There are 4 of them. I think 2 big ones (0.022uF) are not that dangerous, because they are connected across the switch.
But the other two 1000pF are across mains.

4 of them? I see the two 0.022uF sitting next to the transformer, where are the other two?

[kirill_ka]

There are 4 of them. I think 2 big ones (0.022uF) are not that dangerous, because they are connected across the switch.
But the other two 1000pF are across mains.

4 of them? I see the two 0.022uF sitting next to the transformer, where are the other two?

See reply#34

[kirill_ka]

No problem, would love to know if you find any quirks from doing a bottom side install.

Well, not likely The socket installation is much cleaner. And I don't have a spare 3478a to experiment with.