Markfrizb's new SNES pcb's, you need them now!!

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nintendo2600
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Markfrizb's new SNES pcb's, you need them now!!

Post by nintendo2600 »

Hey Guys,

I just wanted to give a quick shout out to Mark's new SNES pcbs. These
things are like a swiss army knife SNES board. They can do pretty much
any game, multigame, hi\low\ex, combos, all the logic is built right on
the board so there is no messing around adding 245's or 139's or SRAM
cause it's all already there! You name it this board has it! If you're looking
for brand new SNES boards shoot him a PM. I dunno how many he has
but I don't see them lasting long. These are by far the best SNES pcb's
I've seen made to date. Don't buy one, buy a dozen.

Shawn
Markfrizb
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by Markfrizb »

Thanks for the shameless plug Shawn. :) Glad you like them.
This is the pcb he is referring to if any one is interested... http://youtu.be/h8cFKcPRWkw
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getafixx
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by getafixx »

What is the cost on those?
Markfrizb
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by Markfrizb »

getafixx wrote:What is the cost on those?
Current pricing is $15 + shipping.
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nintendo2600
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by nintendo2600 »

Markfrizb wrote:
getafixx wrote:What is the cost on those?
Current pricing is $15 + shipping.
minus tons of headaches too!
DNSDies
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by DNSDies »

Might be good for a dev board or test board, but I don't see these replacing sports games/Japanese horse racing games as donors.

First of all, I get a free shell for each game with the purchase of my crappy 4 for $9 deals from Ebay.
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by Markfrizb »

This cart wasn't made for seasoned pros. It was made so anyone, even those with little experience, or they don't quite know how to wire in a decoder or know where to source the TSOP adapter (poor in quality as they are - the buy-ic ones) or don't have the tools to desolder mask ROMS or don't know which donor to use for xyz game. And I've built ExHiRom games and star ocean on donors.... It is so much easier to burn 2 roms, install and your done on the cart creation pcb vs getting 2 Tsop boards, adding a decoder & wiring it all up. Even my latest Tsop adapter that has a built on decoder, the cart creation pcb is still easier to use vs using a donor. However, making a single Rom game using my Tsop adapter that marries to the back side of a mask Rom is pretty damn easy too.
http://youtu.be/5QefJWQ12u4
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koitsu
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by koitsu »

Sorry for the semi-off-topic question relating to hardware, but: I've always been curious how that "stacking" of chips actually works. It looks like you've got two flash chips on small PCBs (presumably that's the TSOP stuff?) stacked atop one another before being soldered to the mainboard. How exactly does the underlying hardware work with that, e.g. say both chips were 8mbit, how given that configuration would one be able to access the first chip vs. the second, especially if they share the same pins?

This isn't the only place I've seen this done; I've seen commercial motherboards or random consumer products where literally two DRAM or flash chips are stacked on top of one another before being soldered to the board, but I have no idea how this actually manages to work.
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by Markfrizb »

koitsu wrote:
Sorry for the semi-off-topic question relating to hardware, but: I've always been curious how that "stacking" of chips actually works. It looks like you've got two flash chips on small PCBs (presumably that's the TSOP stuff?) stacked atop one another before being soldered to the mainboard. How exactly does the underlying hardware work with that, e.g. say both chips were 8mbit, how given that configuration would one be able to access the first chip vs. the second, especially if they share the same pins?

This isn't the only place I've seen this done; I've seen commercial motherboards or random consumer products where literally two DRAM or flash chips are stacked on top of one another before being soldered to the board, but I have no idea how this actually manages to work.
The memory parts have enable pins. Basically, multiple memory parts (roms, srams, etc) all share the same address lines and data lines. So you can stack them because they All share the same buss lines. The OE and CE pins (output enable and chip enable) lines are controlled by a decoder - or I like to refer to them as traffic cops. They make it so only 1 memory part can be active at any 1 time. Can't have 2 memories talking at the same time. Buss contention. So when the CE or OE lines are pulled high, it makes that memory invisible to the buss. That's called tristate. So stacking the chips is just an efficient way to buss the lines (except the oe and sometime CE). Most of the time, the CE lines are bussed also so only the OE line is used to enable or disable the memories via the traffic cop (decoder). It's no different than having them all in-line with traces.
Because the ExHiRom games add another rom to the buss, a decoder has to be added to control when the 2 TSOP roms output. My little pcb in the video above has a decoder already on the pcb so it's just a matter of setting a few jumper to configure the tsop's.
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MaarioS
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by MaarioS »

Basically I gotta agree, it is actually much more easy to modify a specific donor board than messing with all those settings on 1 everything-in-1 universal bigass board :D . But on the other hand, it is very good as a testing board and I'm really impressed it supports literally everything, including all LO/HIRom games (even Star Ocean) and even multicarts on the same board.... just wow, I'm speechless

By the way, if you don't mind answering.... how come you managed to run Star Ocean on a regular board??? I'm so much curious
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nintendo2600
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by nintendo2600 »

DNSDies wrote:Might be good for a dev board or test board, but I don't see these replacing sports games/Japanese horse racing games as donors.

First of all, I get a free shell for each game with the purchase of my crappy 4 for $9 deals from Ebay.
If you can get 4 for $9 I'd love it if you shared these deals :) Even so, these new boards Mark has are way better
than messing around with donors and TSOP chips. EPROM, in the socket, solder a couple jumpers, done. To me
that's worth $15 all day long.
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by Markfrizb »

MaarioS wrote:Basically I gotta agree, it is actually much more easy to modify a specific donor board than messing with all those settings on 1 everything-in-1 universal bigass board :D . But on the other hand, it is very good as a testing board and I'm really impressed it supports literally everything, including all LO/HIRom games (even Star Ocean) and even multicarts on the same board.... just wow, I'm speechless

By the way, if you don't mind answering.... how come you managed to run Star Ocean on a regular board??? I'm so much curious
There's only 4 settings. How can that be difficult?

All the other jumpers/settings are related to multigame usage. Star ocean requires 2 additional jumpers.

In making this, I wanted it to serve my purposes (the multigames) as well as an easy way for customers to make single use games. I didn't think Star Ocean would be a big demand so it wasn't a big focus in the design.

Seriously, aside from the cost differences, how could modding an original donor be easier than mine? Mine, you just program a rom and install. The donor, you have to remove the mask rom, then install a tsop adapter. If you are buying the tsop adapters from buy-ic, how much are you spending for those? $10??? + donor cost + time and trouble. If making a exhirom game with a donor, then you have to buy 2 of the tsop adapters (thats's $20 from buy-ic). The 27c322's are about $1.60 on eBay.

Let's not forget you can install sockets too and the shell will still close (as the video shows).

Anyways, they aren't for everybody. :)

There's certainly a place for the donors .... Like the no SRAM, basic pcb that just has 1 rom. But if you game requires SRAM, mine is a pretty good alternative.
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nintendo2600
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by nintendo2600 »

Markfrizb wrote:
There's certainly a place for the donors .... Like the no SRAM, basic pcb that just has 1 rom. But if you game requires SRAM, mine is a pretty good alternative.
Well unless you're just a glutton for punishment that is..lol... :lol:
DNSDies
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by DNSDies »

nintendo2600 wrote: If you can get 4 for $9 I'd love it if you shared these deals :)
Go to Ebay, video games category, wholesale lots, sort by price & buy it now.
There's usually someone doing a 3-4 "sports game" pack for $5 with $4 shipping.

It's kinda random, but I got 2 of the 4 game packs and it had 2 lorom/ 36 pin 64k donors, 2 lorom 16k donors, 2 hirom 64k donors, and double 32 pin mask rom 64k donor.
Also had a crappy tennis game with no sram that I used for a bomberman hack.

Also, Japanese game lots are usually GREAT.
I got some crappy horse racing games, 4 for $10. Two hirom donors with 64k, one with 2x36 pin slots (used it for Tales of Phantasia and Crimson Echoes), one Lorom 36 pin with 64k, and a hirom with 256k and 36 pin slot.
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Re: Markfrizb's new SNES pcb's, you need them now!!

Post by qwertymodo »

koitsu wrote:
Sorry for the semi-off-topic question relating to hardware, but: I've always been curious how that "stacking" of chips actually works. It looks like you've got two flash chips on small PCBs (presumably that's the TSOP stuff?) stacked atop one another before being soldered to the mainboard. How exactly does the underlying hardware work with that, e.g. say both chips were 8mbit, how given that configuration would one be able to access the first chip vs. the second, especially if they share the same pins?

This isn't the only place I've seen this done; I've seen commercial motherboards or random consumer products where literally two DRAM or flash chips are stacked on top of one another before being soldered to the board, but I have no idea how this actually manages to work.
Mark already covered this pretty well, but I'd also like to mention that this is basically exactly how boards with 2 ROM chips or even ROM + SRAM work, but they just use board traces to connect instead of stacking. The thing is, when you use 2 identical chips, all of the pins that you want to connect together just so happen to be in the same place, so you can stack them in order to connect them. They share the same exact address and data bus, the only difference is the chip select pin (or sometimes the output enable is used instead, Nintendo seemed to swap /CS and /OE whenever they felt like it because it really didn't matter for MaskROMs). You do have to lift the chip select pin on the top ROM, because (as the name suggests), that's how you select which chip actually drives the data bus. So that's the part you probably missed in seeing all of the other pins connected together. The chip select signal is still separate for each chip, which are then connected separately to the mapper.

The way memory-mapped I/O works from a hardware perspective is that you have a shared address and data bus for all of the chips, then you have 3 control signals, write enable (/WE), output enable (/OE, you can also think of this as a read enable, in contrast to write enable), and chip enable (/CE, aka chip select, /CS). Sometimes you will also see a CE2 on SRAM, but what that actually does is that you tie it to the Vcc rail through a pull-up resistor and it disables the chip until the voltage rail is stable, so while it is a secondary chip enable, you would not use it as a chip select. It's sometimes referred to as /RST instead. /OE and /WE can be connected between all of the chips on the board if you want, but you need a separate /CE for each one. If you want to read from a chip, you set the address bus, pull /CE low on the specific chip you want to read from, then pull /OE low and /WE high to indicate a read, at which point (after a propagation delay) you can read the data off the data bus. A write is similar, set up the address, set up the data bus, pull /CE low on the chip, then /WE low and /OE high. Any chip with /CE high simply doesn't respond to the /OE and /WE signals, so that's why it's ok for those two to be shared, and it's why you don't get bus conflicts despite all the different chips on the board (assuming everything is working correctly, and also it's worth noting that this is the same bus used internally by everything inside the console as well, the cart slot is just an extension of that bus). So now, you have multiple chips on one board and you want them to be mapped to certain address ranges. That's where the mapper comes in. It basically just taps into the address lines, and then based on what address you put on the address bus, it selects the proper chip and sets the /CE outputs properly.
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