Hi,

I had similar situations with my 7300/180.

I guess two cases.

First, zTerm setting:

Apple suggest :
http://developer.apple.com/technotes/tn/tn1061.html

38400 baud (typically 38.4 but some versions of OF may use 19.2 also) 
No parity 
8 data bits 
1 stop bit 
XON/XOFF handshake 
ANSI/VT102 terminal protocol 
--------
I tried VT100 terminal and it works!

Second, Open Firmware gone mad!

I've met this state twice,

One : after I got rid of my HDD. (to exchange bad hard disk 
      for a newer one).
      OF setting was scsi-int/sd@0:0 but, no Hard disk was there.
      so, OF shows me nothing, Even Co.+Op+O+F key.
     -) I then tried all thing, removing RAM, HDD, and reinstalling...
      But no other things worked.
      Only original setting worked!
      I put bad hard disk in place return, and boot with Co.+Op+O+F
      key. then tried "BYE" command with MAC OS 8 CD in CD-ROM.
      and next I booted with CD twice more.
      and  unplugging HDD and reboot: all things were fine.
      That I changed my hard disks. and re-installed NetBSD.

Two : when tring Co.+Op+P+R doesnot work, I removed battery on
      motherboard. then 10 minutes smoking (Power cable not engaged
      also.) ...
      Give mac battery again, and boot.
      Mac shows me smiling screen. (I almost punched that smiling mac.)


After all, I do not use  OF-Patch.
I just use with serial console with mac.
(I do not use X-window, just Apache + PHP server)
serial console with my windows 2000 pc make more sense to me,
because I can use Hangeul(Korean language) in console.


One thing omitted, I plugged serial cable in modem port between
macs. and connect zTerm.

I hope your mac should show its smiling mac icon again.


Thanks,
Inseo-Park.

PS) serial console in NetBSD sometimes hangs up.
but in Debian/GNU Linux runs happily.

I cannot figure out what is difference between two getty.