PIV SD/FF vs Indivision SD/FF Question

[alexh]

Have you tried to change the SD/FF settings to alter the output scan rate?

I bet you've still got it set to it's default of 50Hz.

Chapter 6

Use PicassoModeTNG to change the settings.

[alexh]

@Crumb
Do many demos use SuperHighRes screens though?

@ Lockon_15
1) Indivision AGA isn't a gfx card.
2) RAW bandwidth of PIV is much higher. Just see how HighGfx sucks speed wise compared to PIV RTG screens.
3) Picasso IV scandoubler has similar capabilities in that it can scan rate convert too. No doubt that it is inferior to Indivision AGA but the PIV's RTG more than makes up for it.
4) Indivision AGA can be difficult to fit and it's connection reliability long term is unknown.

How can the Indivision cards become RTG cards? They don't have a direct connection to the 680x0 bus so I imagine they are limited to exisit in Chip RAM address space and so have to compete with all the other Amiga custom chips for bus access? Without another bus connection to the CPU, I imagine that RTG performance would be poor?

Such a shame they didn't make a Zorro III GFX card slot version of Indivision AGA for A4000.

I paid less than £150 for both my PIV cards second hand.

[alexh]

@lockon
Thanks for the link. I'm still very curious to know how it can work well when it is contending for bus access with all other Amiga custom chips. I wish I truely knew about the bus architecture of the Amiga. Perhaps the Denise's register / data interface is connected to a different bus, separate from other chip-ram accesses, capable of being accessed simultaneously with the CPU?

2xPIV for 150 quids...what are the odds of that steal happening again ?

I think you misunderstand. 2xPIV for 300 quids (150 each)

[alexh]

They said exactly what I thought they would which is the bus which the Indivision ECS is on is slow and subject to contention with the other Amiga chips making it much slower than Zorro III which means it's potential as an RTG framebuffer card is diminished somewhat.

They claim to have 7Mbytes/sec transfer rates. If this is an average speed, under load, this is better than Zorro II (4Mbyte/s) so there is hope.

Still, if you have an Indivision-ECS it's a nice free function.