How to read certain memory values?

[rorirub]

I'm looking for an application for the Saturn that I can use to read certain hardware registers on a retail saturn. Right now I'm using the Save Game Manager by rockin-b, which has a memory viewer function. This would be perfect, since it shows a full hexadecimal view. There are 2 problems with it however:

- I can only scroll the memory address, I can't specify one manually. The app starts at 0x6004000, and from there to scroll down to the 0x5b00000 region takes a lot of time.

- Once I reach 0x5e13e1d during the manual scrolling, the application locks up! Is there something in that area which is unreadable?

I'm trying to check the following addresses on my saturns, they are version registers for each chip:

- 0x05b00401 (SCSP)

- 0x05fe00c8 (SCU)

- 0x05d00016 (VDP1)

- 0x05f80006 (VDP2)

(are there any other version bits elsewhere? These are the only ones I could find in the documentation.)

edit: if I try to dump these regions with the memory dump function, the viewer gets stuck at 0x58e6fc2. Also, it hangs at different positions depending on how fast I scroll. So the area between 0x5800000 and 0x5ffffff is more or less inaccessible.

 

[mrkotfw]

I'm looking for an application for the Saturn that I can use to read certain hardware registers on a retail saturn. Right now I'm using the Save Game Manager by rockin-b, which has a memory viewer function. This would be perfect, since it shows a full hexadecimal view. There are 2 problems with it however:

- I can only scroll the memory address, I can't specify one manually. The app starts at 0x6004000, and from there to scroll down to the 0x5b00000 region takes a lot of time.

- Once I reach 0x5e13e1d during the manual scrolling, the application locks up! Is there something in that area which is unreadable?

I'm trying to check the following addresses on my saturns, they are version registers for each chip:

- 0x05b00401 (SCSP)

- 0x05fe00c8 (SCU)

- 0x05d00016 (VDP1)

- 0x05f80006 (VDP2)

(are there any other version bits elsewhere? These are the only ones I could find in the documentation.)

edit: if I try to dump these regions with the memory dump function, the viewer gets stuck at 0x58e6fc2. Also, it hangs at different positions depending on how fast I scroll. So the area between 0x5800000 and 0x5ffffff is more or less inaccessible.

Aside from anything on the CPU-Bus, those addresses need to be cache-through addresses. Are you wanting to find out information on the Saturn? You're better off searching reading 0x06000200 for the Boot ROM version.

Why do you need this information? The information that I think will be most useful is physically looking (opening it up) at the board version of the Saturn.

 

[antime]

I'm looking for an application for the Saturn that I can use to read certain hardware registers on a retail saturn.

Charles MacDonald wrote a memory viewer program that lets you specify the start address, but as it always displays a screenful of data you can still end up accessing regions that lock up the hardware.

Aside from anything on the CPU-Bus, those addresses need to be cache-through addresses.

You should use cache-through addresses, but you don't absolutely need to. Since the registers hold a fixed value there's no risk of reading stale data, but since the CPU will fill a full cache line you may end up unintentionally accessing memory regions that cause bad side-effects.

 

[rorirub]

I already opened up quite a bunch of saturns, and collected quite a lot of serial numbers. For example, the VDP2 chip can be:

315-5690 FH3006

315-5690-02 FH3006

315-5890 FH3006B

315-5890-02 FH3006B

315-5964 FJB006

I want to check how the internal revision numbers reflect all these versions.

The boot rom version has nothing to do with this, and can be determined by opening up the saturn and checking the serial of ic7 (EPR- or MPR-xxxxx). However, all of them but the Samsung Saturn show their version number somewhere when you boot up the machine, so you don't even need to open them up.

 

[rorirub]

Charles MacDonald wrote a memory viewer program that lets you specify the start address, but as it always displays a screenful of data you can still end up accessing regions that lock up the hardware.

This one works perfect. It still locks up on some addresses, but I can skip through them with B.

 

[antime]

If you haven't seen it already, you might find this document interesting.

 

[rorirub]

I've seen it, it's extremely inspiring. A shame it's missing date codes on the chips, though.

 

[ExCyber]

The boot rom version has nothing to do with this, and can be determined by opening up the saturn and checking the serial of ic7 (EPR- or MPR-xxxxx).

There are Saturns with EPROM IPL? Guess I haven't disassembled enough of them.

 

[rorirub]

There are Saturns with EPROM IPL? Guess I haven't disassembled enough of them.

So far I've seen them for the 1.00 japanese bios, 1.01 hi-saturn bios, and the pal one. All of them on VA0 or 0.5 boards, with the DIP packages.

If you disassemble your saturns, make sure you post pictures of them!