# Agnus

The one thing I've always liked about Amiga computers is that the custom ICs always have interesting names.
At first glance Agnus seemed like a mis spelled Agnes. When I dove into the manuals I saw the interesting work that the Agnus IC needs to do.

You can consider the Agnus as the direct memory access broker in the Amiga.

A practical example of Agnus usage

* Noise Tracker
* mod data
* Paula

Noise Tracker request0 mod playback on Paula

* CPU interrupt
* Agnus DMA interrupt
* Data playback on Paula

Noise Tracker request1 on Paula
* Agnus DMA interrupt
* Data playback on Paula

As you can see the central processing unit is interrupted only once; all consecutive communications goes through the Agnus IC immediately to Paula.
This Architecture Made it possible to use such a light CPU while The machine did extreme heavy lifting, for it's memory footprint.

Quote
>Agnus is the Address Generator Chip. Its main function, in chip area, is the RAM Address Generator and Register Address Encoder which handles all DMA addresses. The 8361 Agnus is made up of approximately 21000 transistors and contains DMA Channel Controllers. The Blitter and Copper are also contained here. Originally Agnus was fabricated in 5 μm manufacturing process like all OCS chipset.

Agnus features:

>Memory controller ("Chip" memory that can be accessed by the processor and the chipset)
The Blitter, a bitmap manipulator. The Blitter is capable of copying blocks of display data, or any arbitrary data in the chip memory, at high speed with various raster operations as well as drawing pixel perfect lines and filling outlined polygons, while freeing the CPU for concurrent tasks.

https://en.wikipedia.org/wiki/MOS_Technology_Agnus

https://en.wikipedia.org/wiki/Amiga

https://en.wikipedia.org/wiki/Direct_memory_access

#RetroComputing #Retro #Gaming #OCS #ECS #AGA #Amiga #DMA #interrupt

Guided Meditation Interrupted by Ad for Worlds Strongest Knife

https://fed.brid.gy/r/https://thehardtimes.net/culture/guided-meditation-interrupted-by-ad-for-worlds-strongest-knife/

“We must #protest. #Interrupt. #Disrupt. #Strike.
And above all — prepare for massive #boycotts.
Not temporary boycotts. Not symbolic ones.
Permanent #divestment from the #monopolies that bankroll #authoritarianism and manufacture #oligarchs.”

https://www.survivorsguidetoearth.com/

#Communications expert shares how to confidently #interrupt someone who won't stop #talking

https://www.upworthy.com/communications-expert-shares-how-to-confidently-interrupt-someone-who-wont-stop-talking-ex1

STM32 Basics #4 - Interrupts and the NVIC

In this Basics video we are going to cover STM32 NVIC and Interrupt handling.

#STM32 #STM32CubeMX #STM32CubeIDE #NVIC #Interrupt #STM32World

https://www.youtube.com/watch?v=bYdW-IPupI0