Adventures with I2C & Minerva Mk2

[t0nyt]

Have you got a picture of the chip to see what the label looks like?

You did mention the possibility of them being suspect...

The IC is blank (same on all 5), this is an image of the board with IC (taken before I changed the ID)

EDIT: just realised that one’s not blank! Will try and read it and post back

[t0nyt]

Have you got a picture of the chip to see what the label looks like?

You did mention the possibility of them being suspect...

With a bright light the text is visible

[t0nyt]

Decided to expand the scanner slightly to include device names to make it easier to recongnise new devices

Code: Select all

100 WHEN ERRor
110   f=0
120   CONTINUE
130 END WHEN
140 CLS: PRINT "SCAN STARTING"
150 c$=CHR$(164) & CHR$(255)
160 FOR x = 8 TO 119
170   f=1
180   r$=I2C_IO(c$,0,x,0)
190   IF f=1 THEN
200     PRINT "Device Found at " & HEX$(x,8) & " (" & HEX$(x*2,8) & ") ";
210     SELect ON x
220       = HEX('20') TO HEX('27'): PRINT "PCF8574 TI (LCD)"
230       = HEX('40'): PRINT "HTC21D"
240       = HEX('50'): PRINT "Minerva NVRAM"
250       = HEX('50') TO HEX('57'): PRINT "AT24C256 (32K)"
260    REMark   = HEX('23'), HEX('5C'): PRINT "BH1750 (LUX)"
270       = REMAINDER : PRINT "UNKNOWN"
280     END SELect
290   END IF
300 NEXT x
310 PRINT "SCAN COMPLETE"

Sample output (device names slightly different to the updated code above)

[t0nyt]

I think we should get you a "Member of the I2C Club" badge now

Does it have flashing lights? Controlled by I2C?

[NormanDunbar]

Exactly. I laid out the pseudo code for a scanner near the start of this thread

I thought you had, but damned if I can find it

My bad, wrong thread! It's at viewtopic.php?p=66959#p66959 if you still need or want it.


Cheers,
Norm.

[t0nyt]

Exactly. I laid out the pseudo code for a scanner near the start of this thread

I thought you had, but damned if I can find it

My bad, wrong thread! It's at viewtopic.php?p=66959#p66959 if you still need or want it.


Cheers,
Norm.

Thanks Norm. I went back and looked at that thread and still didn't see it. Doh

Have copied and pasted your post into a text doc so I don't lose it again!

Many thanks
Tony

[t0nyt]

No idea on your problem!

But not all i2c addresses are valid so you can speed up your loop by skipping the invalid ones!

https://www.i2c-bus.org/addressing/

So if my conversions are correct the valid addresses run from 8 to 119, will adjust the scanner code thanks

[Pr0f]

Have you got a picture of the chip to see what the label looks like?

You did mention the possibility of them being suspect...

With a bright light the text is visible


IMG_5047.jpeg

The K prefix seems to be used by several manufacturers - Not sure on the other codes under the part number - usually this year and month of manufacture. With some chips I've seen surface colouration changes that seem to suggest laser etching of the original part number and then printing over the top - but I'd have to say that's probably not the case here - the one that works - that's responding as your would expect, all be it to 2 addresses.