Talk:Amiga Original Chip Set

TODO from article
I moved this from the article (this is where it belongs):


 * TODO:
 * List chips and separate functions of every chip in their new entries.
 * Better explanation of resolutions. lores, hires, overscan, interlace, ham, etc.
 * Merge the above feature list..
 * Organize all better
 * Move to Amiga chipsets and make redirects?

&mdash;Frecklefoot 17:23, 18 Nov 2003 (UTC)


 * Where should the Amiga specific disk drive controller be presented? Amiga system differs from PC systems
 * CIA chip explanation has not been created
 * Serial port capabilities should be explained somewhere. Perhaps refer to a more generic serial

device. &mdash;Shd Mon Jan 3 15:53:49 UTC 2005

A2500
Did the Amiga 2500 ship with OCS or ECS or AGA?? --Tonsofpcs 21:23, 13 August 2005 (UTC)
 * The "A2500" is just a marketing name for an A2000 bundled with an accelerator card (also available separately). So it shipped with whatever A2000s were shipping with at the time. Mirror Vax 00:18, 14 August 2005 (UTC)

ICS (Initial Chip Set)
My early 1985 A1000 (which would go very high on ebay) does NOT have Original Chip Set, but Initial Chip Set! So I would not say that OCS is the very first chip set of the Amiga. -andy 85.176.228.48 (talk) 23:04, 7 February 2008 (UTC)

What happened to Gary??
I had one of the earliest A500s, and I remember opening the case. I'm pretty certain that there was also a chip labelled GARY on the motherboard. I seem to remember reading about the chipset (in Amiga Format or Commodore World), and I think Gary did the I/O. We should not forget about Gary. Jason404 (talk) 12:09, 28 June 2010 (UTC)
 * I've started Amiga custom chips to point out the other members of the team. ;-) Zac67 (talk) 21:43, 2 July 2010 (UTC)

Consider Renaming?
Rename this page from "Original Chip Set" to "Amiga Original Chip Set". Most of the other Amiga chipset pages are titled as "Amiga ..." which conveniently groups them together on the Category:Graphics chips listing. OCS is floating out there alone. — Preceding unsigned comment added by 198.184.5.252 (talk) 14:20, 14 March 2013 (UTC)


 * Done. Musaran (talk) 20:09, 18 November 2023 (UTC)

Sprites on the same scanline
The copper description says that after modifying sprite registers the sprite "will be drawn again, even on the same scanline." Is this really correct? Don't we need to wait for the next scanline to get a DMA slot for new sprite data? Ebenupton (talk) 22:16, 22 January 2014 (UTC)


 * That is somewhat correct: the sprite can be reused within the very same scanline, but the DMA channel can't fetch new data – the cloned sprite will look exactly like the 1st one. Zac67 (talk) 19:07, 23 January 2014 (UTC)

Paula volume levels
The article has two different numbers for volume. In the lead it gives 65 levels (including 0 for no volume), but later it states volume is a "6 bit value" with 64 levels.

I pulled out my "Amiga Hardware Reference Manual" (an official CBM publication) 6th reprint (August 1988) and it says on pp139-140 that it is a 6 bit value but also says that the range is from 0 to 64 for 65 total possible values. But it also says that you write the volume to bits 0-5 of AUD0VOL, which is 6bits, so only 64 levels (0-63). Thinking there might be errata, and this is corrected in later editions, I looked at the 3rd edition (1991) and the same thing on the same pages.

So, then I checked the technical documentation for Soundtracker and OctaMED and those both support 65 levels (0-64 inclusive). So, that seems to work in practice.

However, there is this source http://amigadev.elowar.com/read/ADCD_2.1/Hardware_Manual_guide/node0017.html which indicates that a seventh bit is used. This source appears to be an online version of the Amiga Developer CD 2.1. 202.92.108.163 (talk) 04:40, 17 June 2024 (UTC -


 * Both might be true. From dim memory, bits 0-5 set the volume from 0-63 and bit 6 forces full volume. Whether 64-127 are all the same I cannot really say, and I don't have a better source than the HRM – that one does state that there's a difference between 64 (0.0 dB), 64 (-0.1 dB) all the way to 0 (minus infinity dB). --Zac67 (talk) 06:37, 17 June 2024 (UTC)