Adventures with I2C & Minerva Mk2

[t0nyt]

Going back to the AT24C256 (32KB) device

The new one arrived today and it does exactly the same as 4 of the original 5

If they ALL did the same it would be better I think but having 1 that works is a bit confusing!

All have the ghost address (address+8), but there's nothing I can really do about that!

Am going to play with my test code to try and work out if it's the write or the read that's failing. Or just my code is duff (have got a much better understanding of how i2c_io works now)

Maybe I also need to look for an alternative device that does the same thing

[t0nyt]

Going back to the AT24C256 (32KB) device

The new one arrived today and it does exactly the same as 4 of the original 5

If they ALL did the same it would be better I think but having 1 that works is a bit confusing!

All have the ghost address (address+8), but there's nothing I can really do about that!

Am going to play with my test code to try and work out if it's the write or the read that's failing. Or just my code is duff (have got a much better understanding of how i2c_io works now)

Maybe I also need to look for an alternative device that does the same thing

Ok, it was my code...

Took one look at the "page" write code and, with my better understanding of i2c_io now, instantly saw the mistake. Have corrected the code in the original post (line 150 needed LEN(v$) to LEN(V$)+2. No idea why one of them worked, I guess that's the faulty one!

No idea what's going on with the "ghost" address though and nothing I can do about it as far as I know

[t0nyt]

I've tried connecting the Speech Synthesiser to my screen (basically a TV with VGA input and a 3.5mm jack for audio input - works fine with QSound output)

But all I get is a very short crackle and then the speech module dies until power cycled

I'm assuming there is some kind of electrical imbalance going on that I don't understand, given my poor electronics knowledge

Does anyone have any thoughts please?

Many thanks
Tony

[XorA]

I've tried connecting the Speech Synthesiser to my screen (basically a TV with VGA input and a 3.5mm jack for audio input - works fine with QSound output)

But all I get is a very short crackle and then the speech module dies until power cycled

I'm assuming there is some kind of electrical imbalance going on that I don't understand, given my poor electronics knowledge

Does anyone have any thoughts please?

Many thanks
Tony

You have the 0v line connected all the way through?

[t0nyt]

You have the 0v line connected all the way through?

There's 2 output terminals labelled Positive & Negative and they all go thru to the same +/- connections at the TV end

I'm assuming 0v = negative?

Thanks
Tony

[t0nyt]

Have soldered a 2 pin header onto the DFRobot (rather than "winging it" with the connections) and the "crackling" was a red herring

What happens is, as soon as you command it to speak your text there's just a single "pop" noise thru the TV speakers and the device doesn't work again without a power cycle

Many thanks
Tony

[t0nyt]

Am beginning to think this is speaker level output and I’m feeding it to what I assume is a line in amplifier. I guess this could be the problem please?

Or maybe it’s actually a digital output, in which case I have no idea what to do

[t0nyt]

Have soldered a 2 pin header onto the DFRobot (rather than "winging it" with the connections) and the "crackling" was a red herring

What happens is, as soon as you command it to speak your text there's just a single "pop" noise thru the TV speakers and the device doesn't work again without a power cycle

Many thanks
Tony

Hmm, just tried it with one of these and it works. Don't understand

IMG_5060.jpeg (35.57 KiB) Viewed 157 times

[XorA]

Two guesses!

1) Impedance of TV is too low and its pulling too much current - put an amplifier between the two
2) Floating earth, the TV and QL don't agree on what 0v is and there is a large voltage differential - stop connecting them it could cause damage.

[t0nyt]

Two guesses!

1) Impedance of TV is too low and its pulling too much current - put an amplifier between the two
2) Floating earth, the TV and QL don't agree on what 0v is and there is a large voltage differential - stop connecting them it could cause damage.

Ok, many thanks

Not keen on having another device I need to power (and remember to turn on/off) so will play safe and stick with the built-in speaker for now

Many thanks
Tony