MCUmall EPROM BIOS Chip Burner Forum
MCUmall EPROM BIOS Chip Burner Forum
Home | Profile | Register | Active Topics | Members | Search | FAQ
Username:
Password:
Save Password
Forgot your Password?

 All Forums
 MCUmall Forums
 True USB Willem Programmer (GQ-2X, GQ-3X, GQ-4X)
 Unused bits left as 00
 New Topic  Reply to Topic
 Printer Friendly
Author Previous Topic Topic Next Topic  

Tuco

Australia
18 Posts

Posted - 11/13/2017 :  12:26:19  Show Profile  Reply with Quote
Hello,

Progrmamer - GQ-4X

I'm trying to replace 2 EPROMs (M27V322 and M27V160) in an old machine.
I've got a dumps of the original chips and the data writes but the unused bits stay at FF.

The problem is the system does a checksum and sees the unused as FF instead of 00 (as in the original chips) and the checksum fails so the device will not boot.

Is there a way of writing those unused as 00 instead of them being left as FF?

Is it as simple as me missing a setting in the programmer?

Michael.
Reply #1

Tuco

Australia
18 Posts

Posted - 11/13/2017 :  22:41:49  Show Profile  Reply with Quote
Can I delete my thread? This issue has been resolved.
Go to Top of Page
Reply #2

anniel

1996 Posts

Posted - 11/17/2017 :  07:56:02  Show Profile  Reply with Quote
quote:
Originally posted by Tuco

Hello,

Progrmamer - GQ-4X

I'm trying to replace 2 EPROMs (M27V322 and M27V160) in an old machine.
I've got a dumps of the original chips and the data writes but the unused bits stay at FF.

The problem is the system does a checksum and sees the unused as FF instead of 00 (as in the original chips) and the checksum fails so the device will not boot.

Is there a way of writing those unused as 00 instead of them being left as FF?

Is it as simple as me missing a setting in the programmer?

Michael.



Yes you simply need to use "Fill Buffer Hex" in the edit menu.
Go to Top of Page
Reply #3

anniel

1996 Posts

Posted - 11/17/2017 :  07:58:12  Show Profile  Reply with Quote
quote:
Originally posted by Tuco

Can I delete my thread? This issue has been resolved.



No, please don't delete and explain how you resolved. It could help other members of the community.
Go to Top of Page
Reply #4

Tuco

Australia
18 Posts

Posted - 11/22/2017 :  19:35:40  Show Profile  Reply with Quote
quote:
Originally posted by anniel

quote:
Originally posted by Tuco

Can I delete my thread? This issue has been resolved.



No, please don't delete and explain how you resolved. It could help other members of the community.


It was resolved because I didn't realise that the adaptor for my GQ-4X had to be modified running 3 wires for addresses A19 to A21 from the main unit board to the adaptor board for M27V32 and M27V160 chips.
Go to Top of Page
Reply #5

anniel

1996 Posts

Posted - 11/23/2017 :  04:24:47  Show Profile  Reply with Quote
quote:
Originally posted by Tuco

quote:
Originally posted by anniel

quote:
Originally posted by Tuco

Can I delete my thread? This issue has been resolved.



No, please don't delete and explain how you resolved. It could help other members of the community.


It was resolved because I didn't realise that the adaptor for my GQ-4X had to be modified running 3 wires for addresses A19 to A21 from the main unit board to the adaptor board for M27V32 and M27V160 chips.



With the GQ-4X if you have the right adapter and the 4 pins have not been cut you do not need the jumper wires. It works via the ZIF.
Go to Top of Page
  Previous Topic Topic Next Topic  
 New Topic  Reply to Topic
 Printer Friendly
Jump To:
MCUmall EPROM BIOS Chip Burner Forum © Copyright 2003 - 2009 Mcumall Electronics Inc. Go To Top Of Page
Generated in 0.17 sec. Snitz Forums 2000