Planning an 80188 ECB single board computer
John Coffman
single board computer in the EuroCard form factor using an 80C188
chip. The proposed board, like the other N8VEM boards, has a parallel
interface, serial interface, RTC chip, 512K RAM, and a boot ROM. In
addition, this board will have a Western Digital floppy disk
controller.
This is a link to the currently posted schematic and board layout. We
are still making tweaks to the board, so any and all comments are
welcome.
http://n8vem-sbc.pbworks.com/browse/#view=ViewFolder¶m=80C188%2520project
(look under "Pages & Files" at the "80C188 project" folder.)
--John Coffman
James Moxham (Dr_Acula)
versions of CP/M that would run on this board. Others can probably say
what they are. And I also have a feeling that memory banking is
important. How does memory access work on the board?
Roger Ivie
> That looks fascinating. I have a vague feeling there are newer
> versions of CP/M that would run on this board. Others can probably say
> what they are.
CP/M-86
> And I also have a feeling that memory banking is
> important. How does memory access work on the board?
Since it's an 8088 family processor, same way it does in the PC; there
are four 16-bit segment registers that are shifted left by four bits and
added to form the 20-bit memory address.
--
roger ivie
ri...@ridgenet.net
glen herrmannsfeldt
> Working with the N8VEM project, we are working on a schematic of a
> single board computer in the EuroCard form factor using an 80C188
> chip. The proposed board, like the other N8VEM boards, has a parallel
> interface, serial interface, RTC chip, 512K RAM, and a boot ROM. In
> addition, this board will have a Western Digital floppy disk
> controller.
How about a V20 instead? Then you can run CP/M.
-- glen
Peter Dassow
produce Vxx CPUs anymore.
Regards
Peter
John Coffman
The 80C186 was initially considered due to the wider data path, but
there were two factors that moved us to the 80C188: compatibility
with existing ECB peripheral cards, and board space (160mm x 100mm, or
about 6" x 4").
The V20 and V30 do not have the high degree of integration that the
80C188 offers. Since the 80C188 integrates dual DMA channels, one of
which will be used by the FDC, an interrupt controller used by both
the FDC and UART, and most of the necessary peripheral chip select
logic, it is a great choice for an SBC -- and I really mean a "single
board computer." It is very complete, in a very small form factor.
--John
REF: http://n8vem-sbc.pbworks.com/browse/#view=ViewFolder¶m=80C188%2520project
Steve Nickolas
Plus, you can run CP/M on them, just as on any other x86 CPU...it's just not
Z80 CP/M, but it's still CP/M. >:P
-uso.
John Elliott
: The V20 and V30 do not have the high degree of integration that the
: 80C188 offers.
The V40 and V50, on the other hand...
--
John Elliott
Thinks: This is what a nice clean life leads to. Hmm, why did I ever lead one?
-- Bluebottle, in the Goon Show
glen herrmannsfeldt
(snip, previosly I wrote)
>> > How about a V20 instead? Then you can run CP/M.
(snip)
> The 80C186 was initially considered due to the wider data path, but
> there were two factors that moved us to the 80C188: compatibility
> with existing ECB peripheral cards, and board space (160mm x 100mm, or
> about 6" x 4").
But what software is available for this? Some, in this group anyway,
are interested in CP/M, and not so many other boards are available
for that. I suppose the form factor is interesting, but many
boards are available that can run CP/M-86.
On the other hand, I am getting more interested in FPGA based
boards which can do hardware level emulation of a large number
of different processors. Many peripherals can be added by
writing the appropriate verilog or VHDL code, or finding it
on opencores.org or other open source HDL sites.
I have considered the possibility of an FPGA based board
with an S-100, ISA, Apple-II, and Qbus connector, maybe
also PCI or Qbus. (Though maybe not all are usable at once.)
> The V20 and V30 do not have the high degree of integration that the
> 80C188 offers. Since the 80C188 integrates dual DMA channels, one of
> which will be used by the FDC, an interrupt controller used by both
> the FDC and UART, and most of the necessary peripheral chip select
> logic, it is a great choice for an SBC -- and I really mean a "single
> board computer." It is very complete, in a very small form factor.
I do remember when the 80188 came out. I used to have posters of
the mask images for many processors, including the 80186 and 80286.
I believe also the 80386, and a puzzle of the mask image for the 486.
It might be that by the pentium time the mask image was beyond
the resolution of the printing process, such that no details were
visible anymore.
-- glen
Ruud
> http://n8vem-sbc.pbworks.com/browse/#view=ViewFolder¶m=80C188%252...
As a technician I love the idea. First problem: what about the
availability of the 80C188, especially the pin version?
OTOH I still have various XT boards laying around and all (can be made
to) fit your specifications (or better). I haven't studied the bus yet
but it shouldn't be to difficult IMHO to make an interface between the
ISA bus and yours.
I will follow your project with interest!
Groetjes, Ruud
John Coffman
> Hallo John,
>
> >http://n8vem-sbc.pbworks.com/browse/#view=ViewFolder¶m=80C188%252...
>
> As a technician I love the idea. First problem: what about the
> availability of the 80C188, especially the pin version?
The chip is available primarily as a PLCC; hence sockets that are easy
to solder are readily available. The N8VEM boards are all meant to be
built by anyone handy with a soldering iron. I think this is the
first board to use PLCC's, but with pins on 0.1" (2.54 mm) centers,
soldering them is no worse than soldering a DIP.
>
> OTOH I still have various XT boards laying around and all (can be made
> to) fit your specifications (or better). I haven't studied the bus yet
> but it shouldn't be to difficult IMHO to make an interface between the
> ISA bus and yours.
Bus compatibility with the existing Z80 peripheral boards has been a
requirement from the start. This board MUST be compatible with the
VDU (video display unit) on the 8-bit interface, and with the upcoming
graphics card.
Both address and data paths are 8 bits. (I know the Z80 I/O address
bus is really 16 bits wide, but the older I/O instructions inherited
from the 8080 use only 8 bits; and many, if not most, peripherals are
addressed using only 8 bits.)
>
> I will follow your project with interest!
>
--John
dott.Piergiorgio
>> How about a V20 instead? Then you can run CP/M.
>>
> A V30 instead would offer a 16 bit data bus. But I fear NEC doesn't
> produce Vxx CPUs anymore.
but seems to me that V30 also has the 8080 mode....
Side question, I'm wrong or at least one 8086 assenbler Z80 core can
easily screw the emulated machine's timings because 8086's REP/MOVB
cycles was much faster than Z80's LDIR/LDDR ? (and on 8086, not 80186....)
Best regards from Italy,
dott. Piergiorgio.
dwight
I have a standalone Forth that runs on a 80C186/8. It uses the
chips serial port as a console in/out. It may need slight
adjustment for memory enables but can be handy for
debugging purposes.
Dwight