Enterprise Forever
:UK => Hardware => Topic started by: Zozosoft on 2014.January.03. 11:24:07
-
The first order from China?
-
The first order from China?
The very first order came through ok, but the 2nd for 20 gals has not arrived. I've ordered quite a lot from china without problems now though, so I think the last one may have got lost... or just taking a long time! So I've ordered another 20 from another supplier... but also in china, as you can't get gals cheap anywhere else. :(
-
I just read, that NSA hijack electronic component transfers and install backdoors in those ... it will be the case, I think ... :)
We have to check those parts when they arrive ... :)
-
Otherwise I had very different experiences with ordering from the east, like china or such ...
Sometimes it arrive before the time, sometimes it will not arrive, at all.
So now, I am not surprised of anything ...
-
At my workplace we ordered many things from China, about 10% never arrived :-(
My personal experience about IC-s:
I ordered 10 pieces of new 20MHz CMOS Z80.
It is arrived but the CPUs are refurbished old NMOS Z80s. The top of ICs burnish and printed new fake label. The EXOS 2.4 can display the CPU type (NMOS or CMOS), all are NMOS, and don't work on 10Mhz only 4Mhz (I ordered 20MHz type!), one total dead.
Writed to seller, he sent another pack: 1 are CMOS, and working on 10Mhz, 7 also NMOS and 4Mhz, 2 dead...
Ordered new AMD AM29F040 FLASH ROMs, also burnish and printed new fake label IC-s, the real type are MACRONIX MX29F040...
Ordered WD1772 PH 02-02, also burnish and printed new fake label IC-s... real type WD1772 PH 00-02 which are can't overclock to 16MHz (HD disks handling).
If possible I order from European sellers!
-
In that case what does it mean: burnish
Can you attach a picture about fake IC-s?
-
In that case what does it mean: burnish
Csiszolt translated by google :oops: I hope Szipucsu know better translation.
Can you attach a picture about fake IC-s?
You can found many on the Ebay just search z84c0020pec and look at any China seller...
-
Csiszolt
Maybe furbished, smoothened, polished.
Not only polishing but removing some unnecessary material from the surface, using a grinding machine or something like this. Not a common word for me. Refining the surface of some material. I hope you understand.
-
Perhaps, it seems what I have?
-
Perhaps, it seems what I have?
My 20 CPUs, and many-many an the ebay have a 0512 datecode. And now see at many seller new series with 1128 datacode.
Your CPU 0422...
a) it is real
b) older fake series :twisted:
Need more analyze.
The first suspicious sign what I see when got the cpus: the pins curved wider than all other new DIP ICs!
The second sign: look thoroughly the pins. Furbished pins, but can see the solder tin on pins especially on the inner surface.
Third: EXOS 2.4 detect as NMOS.
-
So, there is a little hope. :) The pins have no refurbished sight.
I will try with EXOS 2.4. But I have to write an eprom to see. Your method will give a 100% result?
-
Your method will give a 100% result?
If it is detected as NMOS then 100% it is have a fake label. The C in the Z84C0020 means the CMOS type.
If it is CMOS then needed a turbo EP for check the maximum working Mhz :-)
I have a 10MHz machine, used it for test the CPUs.
Originaly I wanted the 20MHz CPU, because when I tried 12.5MHz EP then it is worked only few minutes. But I don't know this limit from my 10MHz Z80 or from other components.
-
Yes, I know, what C means. And this was not as "hot", like another A or B signed.
But I have only one "turbo" EP, what is clocked with 6MHz, instead 4MHz. It's not overcloked, it is in the original specification, with some modification. :)
-
what is clocked with 6MHz
It is possible some of the fake 20MHz CPUs will work on 6Mhz, if the original IC are Z80B. Currently I not checked this because my 6MHz machines not have a CPU socket.
(And also possible my 3 dead CPU not dead just original 2.5MHz Z80, re-labeled as 20MHz...)
-
At my workplace we ordered many things from China, about 10% never arrived :-(
My personal experience about IC-s:
Hmm, are these stories about sellers on ebay? I have no personal experiences, but it sounds odd, and everybody told me who "play" with ebay quite often: top sellers (even from China) are quite picky about their ratings, so they want to avoid bad ratings at all price and would never fake chips etc. Then maybe this is not so true, or "bad" sellers were selected for the business?
-
The EXOS 2.4 can display the CPU type (NMOS or CMOS)
Zozo just out of interest...how does EXOS 2.4 know whether it is NMOS or CMOS?
-
Zozo just out of interest...how does EXOS 2.4 know whether it is NMOS or CMOS?
Use the known difference at the "OUT (C),F" (0EDh,71h) undocumented instructions, it is send 0 on NMOS and 0FFh on CMOS.
Z80 LD C,0B1H
OUT (C),F
IN A,(C)
OR A
JR NZ,CMOS
It is also can be tested by the interrupt flag bug.
-
Use the known difference at the "OUT (C),F" (0EDh,71h) undocumented instructions, it is send 0 on NMOS and 0FFh on CMOS
Thanks; I didn't know of that!
-
Only just read this thread fully, very interesting! Out of all the IC's I have ordered from China only 1 lot did not arrive, and the ones which did arrive were genuine (they all worked fine anyway!).
I'll be a bit more wary after reading Zozo's comments...