Intel MDS Further Information

[Steve Thatcher]

At 12:02 AM 10/31/2004, Scott Stevens wrote:

>It appears I have here an 8085 based system.  Is this correct.  It
>also appears that there's an 8080 controller as part of the emulation
>system.  I'm assuming (?) the system would run with the Emulator
>boards (Trace Board and Controller Board) not installed.

yes, the system only requires the IPC board to run and even use the 
internal single density drive

>Some questions:
>
>1.  Is the memory array on the top board (board with 8085 processor)
>the main system memory.  It looks like four rows of 4116x8, for a
>total 64K.


you have 64K of main memory. Actually only 62K is available because there 
is a 2K rom monitor that overlays the top ram


>2.  The system has a built in CRT display, and a keyboard input.
>here is the video generated and keyboard I/O circuitry?

the vertical board in back is the IOC board and generates the vertical, 
horizontal, and video intensity for the display monitor (the video 
controller is the 8275 chip). The same board supplies the interface to the 
keyboard which actually contains a 8041/8042 I/O processor (can't remember 
exactly which one). One thing you will realize with Intel is that they were 
not like all the CP/M computers. Intel used a processor nearly everywhere 
to delegate control and increase speed. Each emulation set you will find 
contains at least one processor. The IOC contains a 8080 along with its own 
eprom control program, as well as another 8041 processor.


>Any and all insights into this system are welcomed.  Probably I'll add
>in any info I receive into the HTML for the page.
>
>Thanks,
>Sc