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)
 getting 27c4001 to read like 27c1001
 New Topic  Reply to Topic
 Printer Friendly
Author Previous Topic Topic Next Topic  

mdr14

3 Posts

Posted - 10/23/2015 :  20:00:02  Show Profile  Reply with Quote
I want the 4 meg 27c4001 to read like a 1 meg 27c1001. do i just change the device offset to ?

Edited by - mdr14 on 10/23/2015 21:39:58
Reply #1

ZLM

2923 Posts

Posted - 10/23/2015 :  22:45:07  Show Profile  Reply with Quote
You do not need to set anything. Just load the 27C1001 data into software and program the 27C4001 should work.
Go to Top of Page
Reply #2

mdr14

3 Posts

Posted - 10/24/2015 :  19:28:01  Show Profile  Reply with Quote
Well, yes. It will write the chip no problem...
But I need to write to the 4 meg chip so it looks like a 1 meg chip.
Go to Top of Page
Reply #3

ZLM

2923 Posts

Posted - 10/27/2015 :  13:10:44  Show Profile  Reply with Quote
Yes. it looks like 1 meg chip. You can use your 1 meg chip data and write to 4 meg chip without change anything. Put the 4 meg chip into your machine and it will work.
Go to Top of Page
Reply #4

mdr14

3 Posts

Posted - 11/05/2015 :  16:08:36  Show Profile  Reply with Quote
ZLM, Trust me, I appreciate your responses. But I am not getting the answer I need from you. I need a 1 meg chip in place. not the 4meg. The machine I am installing them in wont recognize the 4 meg. I need the machine to think it is a 1 meg.
I have done this before where I needed a 1 meg to read like a 512k. I had to change the offset.
My memory sux so I don't remember what I did. I have change the offset. I don't know what value I need to use.

Thanks!!!
Go to Top of Page
Reply #5

ZLM

2923 Posts

Posted - 11/07/2015 :  19:02:00  Show Profile  Reply with Quote
You do not need to set the offset. Write the 1 Meg data into 4 Meg chip. And then place the 4 meg chip into your machine. Your machine will think it is the 1 meg chip.
Go to Top of Page
Reply #6

anniel

1996 Posts

Posted - 11/19/2015 :  15:45:55  Show Profile  Reply with Quote
Pin 30 and pin 31 are held hi or low in your application? Don't forget those are address lines on the 27c4001.
Go to Top of Page
Reply #7

ZLM

2923 Posts

Posted - 11/21/2015 :  17:21:41  Show Profile  Reply with Quote
The pin 30,31 address lines will change if the data size exceed the 27c1001 size.

If you load the 27C1001 data from address 000000, then they do not change while programming and stay low.
Go to Top of Page
Reply #8

anniel

1996 Posts

Posted - 11/24/2015 :  05:23:12  Show Profile  Reply with Quote
Yes ZLM, but on the board if left floating or held high the application may try to read inexistant data
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 0.16 sec. Snitz Forums 2000