| T O P I C R E V I E W |
| caius |
Posted - 12/31/2007 : 10:51:56
Hi all,
I have a TOP2048 USB programmer, I'm trying to program a Fujitsu 27C1000 EPROM.The blank check is good (I also erased the EPROM under ultraviolet light) but when I try to program it, Topwinen (v.2.52) returns this error:
000000:Error! (file=08,chip=ff)
I check the current voltage on pin 1 (VPP) and , when the programming starts, it raises for a while from 3.90 Volt to 9.90 (but sometimes also to 5 or 6 volt).
Programming other EPROM type (27512,2764,27128) is fine, so what colud be the cause of this problem with 27c1000 EPROM)
I hope someone can help me.
Thanks in advance and Happy New Year! |
| 9 L A T E S T R E P L I E S (Newest First) |
| ZLM |
Posted - 01/02/2008 : 11:05:06
if you can program 27128, then the Vpp circuit is fine. Only for 27C1000 Vpp controller is broken. I do not have schamatic, it is never published. |
| caius |
Posted - 01/02/2008 : 02:19:02
quote:
Originally posted by ZLM
If you can not program all EPROMs, then your programmer 12V circuit is stopped working. It needs repair.
Thanks.Do you know where can I put my hand?Is there any schematics of the pcb? I would be glad if you could help me in some way.
Thanks
Update: I try to program a 27128 where the VPP is 21V and it was succesful, so the conclusion is that I cannot program EPROM that require 12V. |
| ZLM |
Posted - 01/01/2008 : 20:52:00
If you can not program all EPROMs, then your programmer 12V circuit is stopped working. It needs repair. |
| caius |
Posted - 01/01/2008 : 11:12:04
Yes, you are right.
I did all you have told me, the conclusion is that I can read all EPROMs (I also tried with a 27128) but when I try to program blank EPROMS (I erase myself them with UV eraser) I obtain the same error :
000000:Error! (file=1st value on the buffer,chip=ff).
So, what can I do?Is the programmer bad? Some weeks ago it worked fine...So, it lose the 12V VPP? |
| ZLM |
Posted - 01/01/2008 : 10:03:57
Try:
1. read a not empty EPROM. So the buffer should not be all "FF".
2. verify the chip with current data buffer. If the chip is verified OK, then the programmer read should be stable.
3. do not remove the chip and just program the chip. If the chip can be programmed correctly, but not program on blank chip, then programmer may lost 12V VPP.
|
| eln_70 |
Posted - 01/01/2008 : 09:03:56
After programming a memory cell of an EPROM, the programmer verifies (for each memory position of the chip) that the EPROM contains the same value as the buffer/file. If a programmer completely fails to write to a specific memory cell, it will still read as FF so assuming that programming is successful after writing a buffer filled with FF is not a safe assumption.
The programming _may_ have been successful but there is no way to know for sure since a blank memory cell is represented by the value FF. To be sure, the buffer needs to contain other values than FF. |
| caius |
Posted - 01/01/2008 : 06:01:57
Update: if i read the blank 27c1000 EPROM , I obtain a buffer filled with all "ff" value (obviously because the chip is empy) and, if I program the EPROM with this buffer, the programming is succesful.So , I assume, the problem is the file I'm trying to program, it's a file from an arcade PCB |
| caius |
Posted - 01/01/2008 : 02:24:14
The EPROM should be good, it passes the blanck check..besides I try also with another EPROM and I obtain the same error:
000000:Error! (file=08,chip=ff)
But , in your knowledge, what does it mean this error? What does it mean "file=08"? "chip=ff" should mean the EPROM is blank, right? |
| ZLM |
Posted - 12/31/2007 : 19:44:49
9.9V is too low to progam the EPROM.
Also, check your chip if it is damaged. |
