Gr.1 and Gr.2 bytes/cycles

[José Pereira]

Hi, me again and more of my doubts/questions:

 

-> Gr.1 and Gr.2 are Char Modes and they are 1byte=8pixels (2:1 ratio) and not like Gr.12/13 where 1byte=4pixels (2:1)

If I have in a 160wide, 20bytes wide the cycle screen lost would be normally like this:

--1st scanline of Charset: 20cycles(nº of byte per Line)+20cycles(20bytes Charset 1st scanline)+1cycle(refresh)+1cycle(DLI Charset initial)

--other scanlines: 20cycles(nº of bytes per Line)+9(refresh)

 

If logic applies here, because it consider each pixel(2:1/colour clock) as 1bit it would be half cycle lost VS ANTIC4 in Chars/bytes per Lines (but only one colour per Char, I know!...).

 

 

 

Am I thinking right?

José Pereira.

Edited March 30, 2011 by José Pereira

[analmux]

--1st scanline of Charset: 20cycles(nº of byte per Line)+20cycles(20bytes Charset 1st scanline)+1cycle(refresh)+1cycle(DLI Charset initial)

EDIT

 

I'm not sure, but AFAIK the 9 refresh cycles will only be cut down to 1 cycle in case of a real so-called "badline". The badline only occurs in Antic 2, 3, 4 and 5 textmodes: i.e. gr. 0, 0+, 12 and 13. During a gr.1 or 2 line, there's enough free cycles inbetween, so the 9 refresh cycles don't need to be cancelled/deactivated.

Edited March 30, 2011 by analmux

[José Pereira]

Thanks, but more than if it is 9or1 cycles for the refresh, most important for what I have in mind is to know if it is:

"20bytes(20chars wide) are 20cycles and not 40cycles like in an ANTIC4 charswide?"

 

 

José Pereira.

[ANTIQ]

yep

[José Pereira]

yep

"yep" means what? "yes" and are 20cycles?

 

Thanks.

Greets.

José Pereira.

[Rybags]

Only 1 Refresh in Gr. 0 badlines in Wide and Std modes. 3 in Narrow.

 

Another thing - text modes will always fetch the character bitmap data on both scanlines in the 2-pixel high modes (Gr. 2 and 13 )

[ANTIQ]

yep

"yep" means what? "yes" and are 20cycles?

 

Thanks.

Greets.

José Pereira.

 

yep

[José Pereira]

yep

"yep" means what? "yes" and are 20cycles?

 

Thanks.

Greets.

José Pereira.

 

yep

 

Yah!...