Prototyping Blog page 6

First pictures of the Camputers Lynx - ISA - VGA Bridgeboard

This is just a picture of the Lynx output through a 3.5 inch reversing LCD monitor. The picture is acceptable in 4896 and 128 (just) modes with a slight one pixel jump every few frames.

This is the Propeller robot it sits on.

okay - the Lynx board at front, connected (well it will be!) through a 40 way ribbon off the expansion bus. This connects to an old 1981 IBM Microboard wich has had the chips removed (used to run a spectrum analyser), and inbetween the Lynx and 16 Bit ISA bus is an EPM7128S CPLD chip. Due to lack of pins a 373 latch is also used to multiplex some of the less well used address lines.

The stack is sitting upside down so I can get to the wiring. Its a tight squeeze but after reversing the backplane it is just possible to put it underneath the Lynx keyboard. The video card is a Cirrus Logic GD5428 with the video BIOS removed. If by any miracle the V30 makes it onto the project then the BIOS chip may come back again, for now everything will be driven by the Lynx ROMs.

The passive backplane is out of an old 486 machine from the early 90's. There are three sockets, ine is hidden under the Lynx board, and one ISA slot (don't know what I'll use that for - possibly plugging the whole sherbang back into an old PC at this rate :) )

I wish I had the patience (and money) to afford PCBs - for now its out with the Kynar - bah hate big busses :((

yes.. that's exactly what I thought too...

...As usual, any comments welcome ....