For many of us 8080/Z80 types, the 6809 had the following properties:-

Two 8 bit accumulators
Two 16 bit index registers
Two 16 bit stack pointers (index capability)
Programmable Direct Page
268 op-codes (1464 variations)
8x8 unsigned multiply
16 bit arithmetic
10 addressing modes
24 indexed sub-modes
Indirect addressing
Auto increment /decrement

This 6809 SBC met the IEEE 696 standard requirements. It had 2K of RAM, 2114's, (jumperable to any 1K boundary) and room for  4K/8K/16K of ROM (jumperable for 2708s, 2716s, or 2532's to any 4K boundary).  It had 20 parallel I/O lines (two 8-bit ports and 4 control), an  RS-232 interface (6 lines and 8 baud rates) and 256 I/O ports (8080 I/O instructions memory mapped).

The manual for this board may be obtained here.  

The board also came with a simple monitor in ROM. The usual things like examine registers, or memory, set breakpoints etc. You could output to a punch memory in Motorola Format or read data in.

The listing for this monitor can be obtained here