These Rockman/Megaman 6 in 1 carts are more prolific now and I decided to try one off of aliexpress.
specifically:
http://www.aliexpress.com/item/Megaman- ... 44e59b955c
A couple of points worth noting here is that this does not function properly on clone hardware. I have a Tri Star Super 8 unit which piggy-backs off a SNES and a few games locked up and would not proceed: MM3, MM6
On original hardware there are no issues and everything works as specified. The issue comes up when speaking about the sound processing of MM1 & 2. Whether on clone or real hardware both games have distortion and thats why I am ultimately posting with respect to this.
Here is an example of the sound troubles on a similar bootleg (pardon the 50hz speed):
https://youtu.be/523qkDi1Zyw?t=53 (also, check the video in the aliexpress link for samples)
I have no background as to the cause pardon searching and seeing the notes regarding the registers [
#115318]. I also wondered if there was a conflict with the mappers and rom types not being implemented properly on cartridge.
All the same, there are cases where the sound is not distorted on MM multi-carts:
https://youtu.be/NOJOX88UHTw?t=170
The issue isn't that the Rockman roms are different from the Megaman roms in the mapper department as I learned so I wondered exactly why this issue exists and what can possibly be done to remedy it. Here is further information as I found elsewhere on the exact circuit board in place on these bootlegs:
Ok on the battery side the chip says:
HSRM20255LM10
F31M 271
Japan
The text in the upper left corner says "Pocket games" which seems to be the brand name of these boards.
As you can see there is what looks like a place to connect a chip as well as a few dip points. The one on the right hand side of the battery is closed. The one next to the chip looks like a solid blob in my cruddy pic, but it's actually 3, and the top two are closed together. It's labeled "j8".
---------------------------------------
The back of the pcb:
It says UNION at the top... it appears to be the pcb manufacturer. The serial on the upper right reads: SMD157D-72 (72 most likely stands for 72 pin as there is a famicom version of this cart). The large white text in the lower right says SMD151212.
On the top left hand side there are solder points for what looks like a diode, a dip and another diode respectively labeled D1 R1 and D2. Since it's labeled R1 maybe the dip is actually a spot for a resistor?
There is a blank spot for a chip on the left labeled U6 and a chip labeled U9 below it.
The large chip to the left is labeled U3 and reads:
MXIC 81325
29GL256EHMC-90Q
3P060800
TAIWAN
The square chip in the center is labeled U1 and reads:
SMD132
2015.11.18
The solder pads (for a dip) to the left of that chip are labeled 5/6K. The one below and to the right is labeled H/V (the rom order dip). The rest of the dip pads on this side of the pcb are unlabeled.
imgs:
http://i.imgur.com/4htrpG1.jpg http://i.imgur.com/j45bo6b.jpg