| · MOTIVATION | 
ComRing software also offers network interface for traditional Null-modem. It may be useful for games that don't handle serial link properly.
| · HARDWARE | 
You should prepare 3-wire ComRing cable:
| line | DB9 | DB25 | ||
| TxD | 3 | 2 | transmit | connected to RxD of next computer | 
| RxD | 2 | 3 | receive | connected to TxD of previous computer | 
| GND | 5 | 7 | ground | common for all computers | 
Cable for three computers:
Cable for four computers:
	You can use Null-modem cable as two-node ComRing. 
| · SOFTWARE | 
To distinguish between different computers in the "network" specify a single letter, identifying your computer. It is the first parameter (and only required) to the packet driver. When you invoke comring a on one computer you can't use a (or A) on others. This letter is used to generate ethernet address.
Number of nodes (computers) is limited to 17.
Syntax is: comring id [parameter]...
You may use following parameters:
com# com port (default: 2) baud=# baud rate (default: 115200, it may be slowed down) nodes=# maximal number of computers connected (default: 3) int=# interrupt for packet driver (hex, default: 60) 
If you're using nonstandard port you should specify:
port=# port address irq=# irq number 
Example: comring A baud=9600 com1
	Note: Comring is supposed to be a DOS program. It's an open
	question how to use it with Windows games.
| · GAMES | 
Invoking commands may look like:
comring B com1 baud=57600You should remember: if one computer will not work correctly, the whole network won't work.
pdipx
game