P96_accell functions in Amithlon startup-sequence to disable/enable hardware accelerated features.

Setconfig NIL: p96_accell 0xff ; all on

Setconfig NIL: p96_accell 0x00 ; all off

When you write this line in your startup-sequence file:

Setconfig NIL: p96_accell 0xff

all you do is give as an argument for “p96_accell” a 255 number (in decimal notation). This number for 0xff (in the example) in hexadecimal or for %11111111 in binary notation. As you can see there are eight bits set to state “1”. This means all the 8 bits (representing all acceleration) are “ON” and all the functions represented by them are enabled (what you want).

You should try passing  numbers like below using the hex 0x. Some examples, you can figure out the rest…

(two groupings of 4 – “1110” is e and “1111” is f so “11101111” is ef)

%00000000 – 00   %00000001 – 01    %00010001 – 11
%00000010 – 02    %00000011 – 03    %00100010 – 22    %00110011 – 33
%00000100 – 04   %00000101 – 05    %01000100 – 44    %01010101 – 55
%00000110 – 06    %00000111 – 07
%00001000 – 08   %00001001 – 09
%00001010 – 0a    %00001011 – 0b
%00001100 – 0c    %00001101 – 0d
%00001110 – 0e    %00001111 – 0f    %11101110 – ee    %11111111 – ff

You can disable all 0x00 (00000000) and then add across (0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, etc.) to find the function causing issues.

In this way you enable only one acceleration function as active. In one of those states you should notice that problems are visible. As an example, let’s say using %00001000 shows graphics corruption in certain programs (paint/image apps).
So to use all the other acceleration functions (which make GFX under Amithlon a lot faster) except the one that causes troubles, you should pass %11110111 as an argument for “p96_accell” in Setconfig. However the arguments in SetConfig are passed in hexadecimal notation. The easiest way to convert the number from binary notation into hexadecimal, or decimal one, is to use a program that allows you to do such a conversion without any calculations on your own.

You can do that for example with TotalCalc available on Aminet:


The number used in the example above (%11110111) is equal to 0xf7 in hexadecimal notation. So the line you should use in your startup-sequence file in our example situation would be:

Setconfig NIL: p96_accell 0xf7
Although replacing the card with the one which is fully supported is another
option 😉