Mega Man X subtank bug

[chronomitch]

I recently began playing through Mega Man X on ZSNES 1.51, and I noticed a strange bug when using subtanks. When I played the game on my real snes back in the day, one subtank would nearly fill the entire health bar. On the latest version of ZSNES, though, it only seems to fill half as much. In other words, at low health it takes 3 subtanks to fill the entire health bar. My memory may be a bit fuzzy on the issue, but I have a feeling that this isn't correct.

I have a save state which can be used to show the bug at rapidshare:
http://rapidshare.com/files/46973829/Me ... t.zip.html

specs:
athlon 64 3700+ @ 2.75ghz
2gb ddr400 ram @ ddr500
nvidia 7600GT

The output from nsrt is below:
---------------------Internal ROM Info----------------------
File: Mega Man X (U) (V1.1) [!].mgd
Name: MEGAMAN X Company: Capcom
Header: None Bank: LoROM
Interleaved: No SRAM: 0 Kb
Type: Normal ROM: 12 Mb
Country: USA Video: NTSC
ROM Speed: 120ns (FastROM) Revision: 1.1
Checksum: Good 0x4CC2 CRC32: DED53C64
MD5: DF1CC0C8C8C4B61E3B834CC03366611C

[Deathlike2]

It looks like a timing issue... IIRC, it is supposed to heal like 3/4 to 7/8 of the bar.

[chronomitch]

Yep. My memory isn't wrong. I just tried it on bsnes, and one subtank nearly fills the entire gauge.

[mytmyke]

Use version 1.0 of Megaman X. The bug is not present there.

[Nach]

Search the forum, it's because I didn't implement open bus fully yet.

[odditude]

IIRC, a full subtank is supposed to refill 28 units of health (the same amount a weapon or boss meter gauge holds). At the beginning of the game, the meter holds 16 units; after all health-max ups are collected, your meter is 32 units tall (and thus holds slightly more than what a single subtank can fill).

[grinvader]

Use version 1.0 of Megaman X. The bug is not present there.

But 1.0 has the copy protection failure. Not really an improvement on playing quality.