Hardware:

The SBC was the first PCB available.

SBC PCBs  (actual photo)

Image: http://n8vem-sbc.pbworks.com/f/IMG_6031.jpg

A completed N8VEM SBC (pre-release PCB)

Image: http://n8vem-sbc.pbworks.com/f/IMG_5960.jpg

Features: 

• Z80 CPU 4MHz (default, can be changed with speeds up to 16Mhz recorded)
• 512K SRAM
• 1M EPROM
• 16C550 UART with connector
• 82C55 PPI with connector
• DS1302 RTC with battery backup with small amount of NVRAM
• Standard expansion bus (ECB bus) with buffers, logic, and connector
• Standard PC drive connector power supply interface, +5V only
• Reset key with external connector
• Power LED

The second is the six slot ECB backplane which the SBC plugs into and allows expansion with ECB bus peripherals. 

ECB backplane and BITC

Image: http://n8vem-sbc.pbworks.com/f/IMG_6718.jpg

The third PCB is the ECB bus monitor which plugs into the ECB backplane and allows full monitoring of all bus states (Z80 address, data, and control) plus implements a variety of debugging tools such as single step mode, trap on address (neat!), selective latching on control bus signals (/RD + /IORQ, /WR + /MREQ, etc).  Several builders have made their ECB bus monitors and it works well.  There are videos available online of it working. 

ECB Bus Monitor

Image: http://n8vem-sbc.pbworks.com/f/IMG_7999.JPG

The fourth PCB just became available and that is the ECB Prototype board which allows builders to make custom peripherals with point to point soldering or wire-wrap construction techniques.  It supports full control, address, and data bus buffering and ECB bus connector.  It provides builder configurable partial IO decoding for easy integration with your N8VEM system.

ECB Prototyping Board

Image: http://n8vem-sbc.pbworks.com/f/IMG_8248.JPG

Photo of actual ECB Prototyping Board in use

Image: http://n8vem-sbc.pbworks.com/f/IMG_8333.JPG