24 Apr
2019
24 Apr
'19
4:55 p.m.
At 08:14 AM 24/04/2019 -0700, you wrote:
On 4/24/19 5:39 AM, Guy Dunphy wrote:
I did try reading it as an 8749. By 'not readable' I meant it read as all FF.
Using a Topmax device programmer; a fairly good brand.
Interestingly when I selected Intel 8749 it actually hung on reading. Repeatably. Never
seen that happen before.
Selecting NEC 8749, it read, but got all FFs.
Considering there's something odd going on, I was quite relieved to verify the chip
still works afterwards.
I hadn't gone as far as getting out the databooks and checking whether 8049 should be
readable.
I thought they are, but the absense of '8049' type in the chip programmer seemed
to suggest otherwise. Unless they
were 'induced' to leave it out to hinder copying?
Shall look into it further.
Guy
The keyboard controller is an 8049. Firmware not
readable.
8049s aren't protected. they are 2k versions of the 8048
and can be read as 8749s