Help fix "The Big Book of Amiga Hardware" Today: AGNUS

[Zac67]

A3000/25 PAL, early '92
Agnus 318069-03 8372B, original part, PAL/NTSC switchable
Denise 390433-02 8373R4PD, orignal part

[Zac67]

@alexh: PAL/NTSC machines use the very same Denise, all vertical blanking timing/data flow is managed by Agnus.

[Zac67]

Sorry, must've misunderstood your post.

AFAIK the early DIP40 Agnuses had different ID codes, a 8361 was NTSC and a 8367(?) PAL - might be wrong. They were definitely not switchable; a friend of mine had a PAL-modded NTSC A1000 that wouldn't do NTSC any more.
I always thought all ECS Agnuses were switchable (my first one was) but obviously this is wrong.

[Zac67]

Hmm, I remember dimly that there was something on the underside...

PS: from A500 PAL OCS (my first Amiga):
8371
2387 21
underside:
Philippines
IM242209
HC-30

[Zac67]

Could you verify that EHB is not working on your 8362R5? I heard it's not supposed to have been in the early revs, but in reality it was always working in production chips.