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Clean version of the Jaguar's schematic


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#26 DEATH OFFLINE  

DEATH

    Space Invader

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Posted Wed Aug 1, 2018 5:10 PM

By the way, in electronics, never leave an unused CMOS input unconnected.
An unconnected CMOS input tends to float between VDD and GND, creating greater power consumption and overheating.
So basically, unused CMOS inputs are connected to GND or VDD through pull-dow or pull-up resistor.

 



#27 atarian63 OFFLINE  

atarian63

    River Patroller

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Posted Wed Aug 1, 2018 5:23 PM

As a side note, they created the CoJag so that the 68020 or alternate CPU (MIPS 3041) had its own dedicated memory so the program was more predictable and it wouldn't have to deal with any of the slowdown from the Jaguar chipset. I ran across one board that was straight up a 586 PC motherboard attached to a Jamma board and the thing even had an AGP slot. It was a Maximum Force board I believe but was clearly no longer a CoJag at that point. No idea why or what trouble they ended up going through to make that all work out.

Yep the last of the arcade series was pc based sadly. I thought it was Site 4 though.



#28 DEATH OFFLINE  

DEATH

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Posted Sun Aug 5, 2018 11:11 AM

sorry but I forgot that the configuration of the Jaguar is much more flexible. In fact, the external data BUS of the DSP can work very well in 16 or 32 bits regardless of the width of the data BUS of the CPU (68000). So the most likely reason why the DSP's external bus is in 16bit mode is that the 32bit mode is buggy and one or more components would have to be added to work around the bugs, if this possible.

To be sure, you have to test. Take your soldering iron!

 
 


#29 DEATH OFFLINE  

DEATH

    Space Invader

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  • Location:France

Posted Sun Aug 5, 2018 12:51 PM

 

sorry but I forgot that the configuration of the Jaguar is much more flexible. In fact, the external data BUS of the DSP can work very well in 16 or 32 bits regardless of the width of the data BUS of the CPU (68000). So the most likely reason why the DSP's external bus is in 16bit mode is that the 32bit mode is buggy and one or more components would have to be added to work around the bugs, if this possible.

To be sure, you have to test. Take your soldering iron!

 
 

 

 

My bad again, the width of the external data bus of the DSP is the same as of the CPU






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