🚀 go-pugleaf

In article <1991Jan15.194359.25217@julius.cs.uiuc.edu> totty@flute.cs.uiuc.edu (Brian Totty) writes:

>	I would actually be curious to know what kind of stuff actually
>	were used in home video games.  Processors, graphic chips, sound chips,
>	amount of memory, etc.

	I got a NEC Turbo Grafix 16 this Christmas, and (naturally) wasted
no time in disassembling it.  Took about 2 hours.

	The circuit board had space for "UPD65006", 64-pin QFP (and
the part number indicates it is a NEC CMOS gate array of some sort)
and "23C1000", a 28-pin DIP, a CMOS 128kB ROM, but both spaces were
empty (the ROM presumably would have replaced the plug-in cartridge).
The actual chips on the board were:

	HuC6260     80 - QFP (i.e. eighty-pin quad flat pack)
	HuC6270     80 - QFP
	HuC6280     80 - QFP
  2@    HSRM20256LM12   28 - flatpack 120 ns SRAM, 32k x 8 bits
	HSRM2264LM10    28-flatpack 100 ns SRAM , 32k x 8 bits
		(with a tin plate soldered over it for shielding)
        21.4772 MHz oscillator
and an eight-pin chip (probably an op amp for the sound circuit).

	I suspect the memory is 32k x 16 bits, that one of the HuCxxxx
chips has the CPU on it, and that the fast memory chip is being run
as the video buffer.  All the 'HuCxxxx' chips are copyright-stamped
'Hudson', which name also appears on the title screens of some of
the video games.

	If anyone wants to pull one of these apart, the only trick
is in building the wrench.  Starting with 0.249"  hex stock in
an indexing head, drill six #66 holes at 60 degree intervals on
a .175" diameter circle.  Then drill the center with a .180" drill
to a depth of 0.140".  Clean out the six holes, cement a short 
#67 hardened rod in each, and grind the end flat.  Chuck it in the
electric screwdriver, and disassemble away!
	Curiously, there is no note on the case stating 'No user
serviceable parts inside', so I trust I have NEC's blessing in
the disassembly effort.

	John Whitmore