Re: Enhanced //e with a 6503??!

[Eric Smith <eric@brouhaha.com>]

"BLuRry" <brendan.robert@gmail.com> writes:
> I recently scored an enhanced //e (verified that it can display
> mousetext and DHGR) -- however, it was sent to me with a processor
> manufactured in mexico, labeled as a 6503.

Seems unlikely, as the 6503 through 6507 are 28-pin chips, while
the 6502 is a 40-pin chip.  More likely the legend is smudged so
that the 2 looks like a 3, or it's a typo.

> processor I would expect to find in any apple //e.  For that matter, my
> vulcan controller refused to start, crashing to the monitor at address

If the monitor worked at all, it's not a 6503.  THe problem with the
Vulcan must be something else.

> I read somewhere that the 6503 was a 6502 that could only address 4k of
> memory.  Is this the case?

Yes, and it's also missing the RDY and Ph1 signals.

> Also, I noticed that this //e (MB dated 1986) has much fewer chips,
> noticably the row of 16 * 4k ram chips (like my 1982 //e)

IIRC the early IIe had eight 64Kx1 chips.

> was replaced by 2 * 32k ram chips. 

Two 64K*4 chips.  Apple only used 32Kx1 DRAMs in the Apple III, and
those were Mostek parts that had two 16Kx1 DRAM chips in Ceramic Leadless
Chip Carriers (CLCC) soldered to an 18-pin ceramic hybrid.

> The 80-column card (also 1986) seems to work
> fine, but is like half the size of my older 1981 model extended 80-col
> card.  Is it just a reduced chip count because of bigger ram chips as
> well?

Yes.