add abox overclocking to Xblast OS

psyko_chewbacca NA repo owner

Damn that's cool!

I didn't think that was possible.

However, overclocking seems to be tied to X-codes values which reside in BIOS bin images. When XBlast loads a hacked BIOS, X-codes values from that BIOS gets used instead of the ones from XBlast OS. When XBlast loads a BIOS, it removes itself completely from memory and the BIOS is loaded straight from flash. XBlast OS then cannot patch on the fly hacked BIOS data.

The only way it could be done would be to manually patch hacked BIOS residing on Xblast modchip's flash through XBlast OS. I'm not too fond of doing this. Patching this means potentially a lot of flash sector erasing and writing as user change values around multiple times when tinkering with it. Most flash chips are rated for 10 000 rewrite cycles, after that, flash cells could degrade to a point were they wouldn't be able to hold data reliably.

XBlast Lite SST49LF080A flash chip is also certified for 10 000 cycles (even if datasheet states up to 100 000 cycles reliability, it's not certified and guaranteed, only expected).

I want to avoid as much as possible reaching that limit and allowing a user to rewrite sectors infinitely could bring reliability issues down the line with the user not understanding why the modchip will not program his hacked BIOS on its flash.

I guess the best of both world would be to implement that feature but not offer it on release builds. A power user who wishes to use it would need to either compile his own build or get an unofficial one that has this feature enabled.

Definitely interested in that one.

2019-03-27T12:14:02+00:00

Comments (2)

psyko_chewbacca NA repo owner
Damn that's cool!

I didn't think that was possible.

However, overclocking seems to be tied to X-codes values which reside in BIOS bin images. When XBlast loads a hacked BIOS, X-codes values from that BIOS gets used instead of the ones from XBlast OS. When XBlast loads a BIOS, it removes itself completely from memory and the BIOS is loaded straight from flash. XBlast OS then cannot patch on the fly hacked BIOS data.

The only way it could be done would be to manually patch hacked BIOS residing on Xblast modchip's flash through XBlast OS. I'm not too fond of doing this. Patching this means potentially a lot of flash sector erasing and writing as user change values around multiple times when tinkering with it. Most flash chips are rated for 10 000 rewrite cycles, after that, flash cells could degrade to a point were they wouldn't be able to hold data reliably.

XBlast Lite SST49LF080A flash chip is also certified for 10 000 cycles (even if datasheet states up to 100 000 cycles reliability, it's not certified and guaranteed, only expected).

I want to avoid as much as possible reaching that limit and allowing a user to rewrite sectors infinitely could bring reliability issues down the line with the user not understanding why the modchip will not program his hacked BIOS on its flash.

I guess the best of both world would be to implement that feature but not offer it on release builds. A power user who wishes to use it would need to either compile his own build or get an unofficial one that has this feature enabled.

Definitely interested in that one.
- 2019-03-27T12:14:02+00:00
professor_jonny reporter
That's what I thought I have sited multiple people saying it cant be done as the clock is shared amongst hardware but there is the code.

It would be interesting if the microcode's could also be replaced as well as I guess they are in the X-codes somewhere also.

I knew it would require patching the bios image but I guess if plans to make a more full featured chip that on the fly patches the bios or a modchip with SRAM that loads the bios image from hdd, nand usb etc... on first boot would be the idea here then you have unlimited PE cycles.
- 2019-03-27T23:59:12+00:00
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