User`s manual

2–6 Hardware Reference RabbitCore RCM2200
programming port so that an externally connected
device can force the RCM2200 to start up in an
external bootstrap mode. The Rabbit 2000 Micro-
processor User’s Manual provides more informa-
tion related to the bootstrap mode.
The programming port is used to start the Rabbit-
Core RCM2200 in a mode where it will download a
program from the port and then execute the program.
The programming port transmits information to and
from a PC while a program is being debugged in-
circuit.
The RabbitCore RCM2200 can be reset from the
programming port via the /RESET_IN line.
The Rabbit 2000 status pin is also presented to the
programming port. The status pin is an output that
can be used to send a general digital signal.
The clock line for Serial Port A is presented to the
programming port, which makes synchronous serial
communication possible.
2.2.3.1 Alternate Uses of the Program-
ming Port
The programming port may also be used as an appli-
cation port with the DIAG connector on the pro-
gramming cable.
All three clocked Serial Port A signals are available as
• a synchronous serial port
• an asynchronous serial port, with the clock
line useable as a general CMOS input
• two general CMOS inputs and one general
CMOS output.
Two startup mode pins, SMODE0 and SMODE1,
are available as general CMOS inputs after they are
read during the initial boot-up. The logic state of
these two pins is very important in determining the
startup procedure after a reset.
/RES_IN is an external input used to reset the Rab-
bit 2000 microprocessor.
The status pin may also be used as a general CMOS
output.
See Appendix C, “Programming Cable,” for more
information.