[comp.protocols.tcp-ip.ibmpc] VT220 8-bit emulation and Telnet Binary mode

beame@maccs.dcss.mcmaster.ca (Carl Beame) (01/16/91)

	I'm just finishing up some testing of a new VT220 emulator and
I have run into a small problem. The VT220 can do both 7-bit and 8-bit
emulation and therefore must be able to have an 8-bit data path at times.
Currently, I send a WILL BINARY/DO BINARY Telnet sequence when 8-bit mode
is entered and a WONT BINARY/DONT BINARY sequence when 7-bit mode is entered.

	This seems correct, but I am getting different behaviour againts
several systems. And against many systems, 8-bit mode is unworkable.
Here is a small table of results when switching to 8-bit mode, the column 
<CR> working indicates whether a carriage return properly terminates an
input line.

System O/S           Responds DO/WILL     <CR> working
================================================================
Multinet VMS		Yes			Yes
Sun OS 4.1  		Yes			No
Solbourne 4.0C		Yes			Yes
SCO V3.2		Yes			No
CS/100 (milking mach.)	Yes			Yes
IBM FAL/VM (line mode)	No			Yes

Do I just give up the idea of using VT220 8-bit mode against Unix
hosts ? Do I ignore Binary mode, since many hosts transmit in Binary
even if the option is not set ?

Comments welcome.

	- Carl Beame
	Beame & Whiteside Software Ltd.
	Beame@McMaster.CA