HP488 as 3.3Volt development platform?

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Stanga
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HP488 as 3.3Volt development platform?

Post by Stanga »

I would like to use the HP488 to develop and test software for use with a 3.3V piece of kit that I am building. I have had few problems with developing 5V products and doing initial testing on them by wiring the HP488 directly into my own projects. But the HP488 has 5V I/O lines, which makes it unsuitable for me to connect my 3.3V lines directly to the HP488.
My question is: is there a solution available that would allow me to use the HP488 at 3.3V or at least get it to accept 3.3V I/O data interfaces from a 3.3V device?

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Benj
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Re: HP488 as 3.3Volt development platform?

Post by Benj »

Hello,

Converting 5V to 3V3 can be tricky. What exactly would you like to communicate with?

On E-blocks we use a MAX3002 device which acts as a bi-directional voltage shifter, it works very well but is fiddly to use if you don't get the circuit just so.

Another good option I often use is to use resistors as potential dividers to convert outgoing 5V signals to 3V3. Incoming 3V3 signals can be connected directly to the 5V microcontroller pin and should still read as a logic 1 when active.

Lastly you could use a buffer IC with open collector outputs or simple NPN transistors with pull up resistors to shift the voltage a single way.

Stanga
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Re: HP488 as 3.3Volt development platform?

Post by Stanga »

I wish to communicate with a couple of chips from Wolfson via the I2C bus. I have tried level shifters etc. but this has its own problems. A direct communication voltage level would offer a far better method.
I'll probably have to modify a HP488 3V3 to try. But I can't find a 2nd HP488 to buy in the Matrix shop. Has it been discontinued?

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JohnCrow
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Re: HP488 as 3.3Volt development platform?

Post by JohnCrow »

Hi
I'll probably have to modify a HP488 3V3 to try. But I can't find a 2nd HP488 to buy in the Matrix shop. Has it been discontinued?
Matrix have discontinued the version 3 HP488 board earler this year.
(Shame Its a great board, was my first purchase from MM years ago and still use it a lot)

This is the replacement, but it works in conjuction with the EB006 programmer.

http://www.matrixmultimedia.com/product ... PHPSESSID=

Not got one of these myself but it does the same basic functions as the HP488 when conncted to the EB006. See the data sheet on the above link.
1 in 10 people understand binary, the other one doesn't !

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