View Full Version : Agnus 8375 318069-18 (A500+) or 8372B (A3000)

27th November 2010, 17:45

I am fitting a GBA1000 and I need the following specific Agnus chip.

Does any body have one spare please.

8375 318069-18 (you can find in some A500 plus), or 8372B (A3000)


27th November 2010, 17:48
The "real" Plus was never releaser with 318069-18. Only with 319544.

Check the post here (http://www.amibay.com/showthread.php?t=5763) and wait few days. I'm expecting from Germany some Agnus chips to experiment in my rev6a board to see if can handle 2mb chip ram.

318 Agnus with 319 are pin incompatible. Is your GBA Board pin compatible with 319544 ?

27th November 2010, 18:12
From the Manual so I get it right, although translated through Google.

Agnus - IC52
Agnus is responsible for the control of the chip-RAM, the video sync signals (HSY, CSY, VSY), and contains the coprocessors copper and blitter. Agnus also contains the complete DMA logic for all six possible sources. On this board 2MB Chip RAM is installed, a reduction to 1MB is not possible.
Agnus was produced in many versions, two of which can be used on the A1000 motherboard. The versions 8372B (A3000) and 8375 (A500 +), part number 318069-18 are used (tested).
When using a 8372B Agnus by placement of a resistor R75 and jumper switchover of the start screen between PAL X17 (X17 jumper open) and NTSC (X17 jumper closed) he will follow. If the components are not fitted to the 8372B starts with a PAL screen.

Note: The Agnus 8375 is not for a PAL / NTSC switch designed. When using this block may jumpers X17 and resistor R75 not be loaded. This would result in a malfunction of the Agnus 8375 with picture noise and unstable performance of the A1000 motherboard. For this reason, the components are listed as "not equipped" located in the circuit diagram.

27th November 2010, 22:01

the 8375-3190544-(revision/region) series is pin incompatible with all other agnii and is only usable on the A500+ as there is a 20 pin shift in signals and voltage. Using this (unadapted) in a socket designed for a 318069 series of Agnus will result in smoke - so best not to use this with your GB1000 motherboard.

However the 8375-318069-(revision/region) is available on the A600 I am pretty confident that this will provide a drop-in replacement but always double check the pinouts.

you can find them in the A600 service manual and the A3000 service manual (available here on aminet) or you can just download here (http://aminet.net/docs/hard/schemclassics14.lha)

1st December 2010, 09:23
Well the Agnus from my A3000 works fine in the GBA1000 board but I only have one so really need one.

1st August 2013, 22:56
Agnus 8375 318069-11 from Kipper2k and 8375 390544-01 from Fieldday are both working in my GBA1000 build. However, the 318069-11 is not working with 32 bit driver from TSOP flash. It does not boot and gets stucked on the stars screen. The 390544-01 shows the nice animation and boots ok.