Going MAD : IIGS <-> PC Serial Transfert

[Zouplaz <pouet@pouet.com>]

Hello, I've been trying and trying again... 

1) I've a brand new mac/pc serial cable
2) This cable works FINE between my old mac and my PC (even at 57xxx 
bauds), been able to setup a ppp link between the Mac and the PC
3) I've decided not to use any com program on the GS side (just to avoid 
any incompatibility between the application and the IIGS serial ports)
I just play with in#1, pr#1, in#2 and pr#2

A) 
- plugged on the GS "printer" port
- in#1
- typing on the PC is seen on the GS (can type basic command and run 
them)
- pr#1
- garbage on the PC side

B)
- plugged on the GS "modem" port
- in#2
- typing on the PC produce nothing on the GS
- pr#2
- garbage on PC side (at best I have once something happening on the PC 
side but could not reproduce)

The settings are the same on both serial ports (GS) :
- device connected : Modem
- Line length : unlimited
- Delete first LF : no
- Add LF : no
- Echo : no
- Baud : 1200 (tried 300 too)
- Data/Stop : 8/1
- Parity : None
- DCD Handshake : Yes
- DSR/DTR : Yes
- XON/XOFF : No

I've tried with 2 PCs
1) Under linux with Minicom
2) Under W2k with Hyperterminal

The too apps where configured 1200 8-N-1

Is that GS broken ??? What else can I try ??? 

Many advices welcome !!! Thank you