Kontron Bootstrap Loader - Manual (Page 23)

Bootstrap Loader
2/98 Page 17 © PEP Modular Computers
Appendix C Bootstrap Loader Start - 1 sec BREAK Signal
On CPUs without an ABORT button, the Bootstrap Loader will enter the command mode on detecting a BREAK character
of at least one second length at the terminal connector.
Since not all terminals are capable of generating a BREAK signal lasting for one second, the modification described below
helps achieve it.
One possibility to generate the BREAK character is to use a special adapter. This adapter contains a switch which can dis-
connect the sending line from the host to the target and connect the disconnected line from the target to the DTR line of
the host (CTS on target). The DTR line of the host has the level of a BREAK character.
This switch may be integrated at any position in the connection line, as long as the DTR/CTS line is connected to the host.
After setting the target, the adapter should be configured so that 1-3 is shorted. On CPUs containing a user LED, the LED
indicates that the Bootstrap Loader is looking for the BREAK. After two flashes the adapter can be configured to 1-2 and
immediately the startmenu should appear. If the LED still flashes, reconfigure to 1-3 and wait for another two flashes. On
CPUs without an user LED wait for approximately 2 seconds and than configure to 1-2. If the starmenu does not appears
immediately, reconfigure to 1-3, wait for approximately another 2 seconds.
A) Adapter at 15 pin connector on OS-9 side
Normal Operation: 1-2
Sending BREAK: 1-3