Perfect :) Updating pseudo code : bool IsDivisibleByTwo(ushort value); bool IsDivisibleByFour(ushort value); enum OperandSize {Byte, Word, Long} bool DisplacementTheoreticalCheckFunction(OperandSize size, ushort displacementWanted) { switch(size) { case OperandSize.Byte : return displacementWanted <...

Long values must be aligned to a 4 byte boundary, not just on an even address.

Do you mean that long values should be divisible by four ?

Hi,

I am not a specialist and I have never done it.
But if you are going to replace the lens bloc why not buy a new one ?
I think there are only two kind of blocks for DC : SPU3200 (yamaha) and SOH-R48 (Samsung).
It depends on GD-Rom drive model.

Hope it helps

Hi, Thanks for your answer. I understand better. The value of the displacement that we give in the instruction for the parameter dsp is what we actually want to do as the displacement (724). The compiler is therefore responsible for internally finding the right value to encode in the 8-bit instructi...

Hi everybody, I hope you're all safe and in good condition :) I have a question about MOVe global data instructions group : MOV.B @(disp,GBR),R0 MOV.W @(disp,GBR), R0 MOV.L @(disp,GBR),R0 MOV.B R0,@(disp,GBR) MOV.W R0,@(disp,GBR) MOV.L R0,@(disp,GBR) I do not understand what the disp value could be ...

Sorry for late answer ... tons of work to do

Well thanks for the script !
It does not solve the problem but it's certainly something on my code ...
The best thing to do is mock some things

What are you deving on?

A little framework very little thing ...

Hi everybody, I make some code using KOS and want to test it on Reicast. I use common self boot tool like bootBreams and obtain a regular CDI file. But the file do not run on Reicast : it froze after the logo screen. The CDI produced is good and boot up on machine. I noticed that using Reicast some ...

Well, replacing 0x8C0102B4 by 0xAC0102B4 in my code solves the issue. Dumping either from 0x8C0102B4 or 0xAC0102B4 locations gave the same consistent result. It is certainly, like you said, a data cache issue linked to the unknown behavior of serial upload tool about managing that. Thanks again :)

Hello everybody, I tried last week a code to compute some things and write result values sequentially using a loop to a field of bytes in main memory at a certain start address. At the very beginning the field of bytes is full of garbage values. After the code was uploaded via serial cable to Dreamc...

I would only add that floatundisf is a part of glibc.
All is said about this topic
Thanks.

Ok: thanks for reply :) First to load directly a constant floating point value like PI in a floating point register, the floating point value must be converted in the "IEEE754 Single precision 32-bit format" . There are some online converters and source code to do this. Then, simply hard c...

Hi, I try to understand how division operations can be made on SH4. As I compile in "single mode", it will be float divisions not double. First, I try to de-compile some C code making division with different type of data. But assembly code is quite difficult to understand (even using 01 di...

Thanks you very much, I will see this more closely.
I am every time amazed the number of things undocumented ...

Hi, On all X86 architecture, the Time Stamp Counter (TSC) is a 64-bit register counts the number of cycles since reset. It is used as a precise timer (a clock cycle delta). https://en.wikipedia.org/wiki/Time_Stamp_Counter Is there something that could be equivalent on SH4 architecture ? I need a tim...

Well, I ask about a reading scenario sector with a specific number on a bootable DC disc (a two or more session disc) using KOS sector read function. First is the sector number a relative or absolute addressing number ? For example, if I ask for sector 14598, is it the 14599 th sector of the entire ...

I re burn my DC Load Serial disk and now it's fine !

Thanks

Using CD ROM sector read function in KOS, is it possible to read all sector on the CD Rom ?
I try to read sector 0 to test but the function return me an error type SYSTEM ERROR (3).

Thanks for help

Hi everybody, I have a little annoying thing : I use a CD ROM disc on my Dreamcast to boot with DC TOOL Serial. Then, sometimes, I need to change the disc (the DC Load boot one) with other disc (a data disc) to load data for testing purpose. But when I change the disc and close the lid, Dreamcast tr...

Thanks

Ok so some questions about CD Rom : Reading ECMA specifications, it seems that all datas are located in the "Program area". I see on Wikipedia that a 700 M Bytes / 80 Minutes CD ROM holds 360000 sectors. Are all those sectors located only in the Program area or is it located in a region st...