Applications Engineering
RTA-FOUSB-MON User’s Manual Rev 1.8
15 / 29
August 2003
e. CE
Pin
This pin is used to enter boot mode for programming of the target M16C MCU. Not all M16C MCU’s have
a CE pin. If a CE pin exists on the target MCU, it should be connected to this pin (refer to serial mode
flash programming in the target MCU’s datasheet). If not, leave pin unconnected.
This pin is in high impedance when in user mode (during debug operations).
If the target MCU’s CE pin is used as input, isolate the driving circuit from the header connection with a
1Kohm resistor.
If to be left unconnected (if users decides to), care must be taken to ensure that the target MCU’s CE pin
has a high signal level using a pull-up resistor during any programming operations.
f. EPM
Pin
The pin is used to control target MCU’s EPM pin (if it exists on the target MCU). EPM pin is used during
programming of the target MCU. If this pin exists on the target MCU (and in Target Powered mode), it
should be connected to the header (refer to serial mode flash programming of the target MCU’s
datasheet). If not, leave pin unconnected.
If the target MCU’s EPM pin is used as input, isolate the driving circuit from the header connection using
a 1Kohm resistor.
If the EPM pin of the M16C MCU is left unconnected (no external circuit and not connected to 10-pin
header), care must be taken to ensure that the target MCU’s EPM pin has a low signal level using a pull-
down resistor during any programming operations.
g. GND – Ground Pin
This provides the common point where the ICD ground and target board ground planes can be
connected. This must be connected to target board’s GND line/plane.
h. RESET – Target MCU Reset Signal
This active low signal is used by the ICD to reset the target MCU. This must be connected to the target
board’s reset circuit or target MCU’s reset pin.
The user must ensure that the ICD can drive the pin to a valid low level with 5mA current.
i. CNVss – Target MCU CNVss Pin
This active high signal is used by the ICD to control the target MCU’s CNVss pin for programming
purposes. This must be connected to the target MCU’s CNVss pin. During normal operation, this pin must
have a low signal. To accomplish this, connect a 10K (nominal) pull-down resistor. See M16C MCU
datasheet on CNVss pin description for details.
j. RXD – Target MCU Transmit Data Output Signal (ICD Receive Data Input
Signal)
This is the ICD SIO receive data input. This must be connected to the target M16C MCU’s boot
UART/SIO transmit data output (TXD) pin.
This pin must be pulled down with a resistor connected to GND. The target MCU’s Kernel program polls
this pin for the presence of the ICD before running the user program. Without the pull-down resistor, the
target MCU will only run the Kernel program program.
This pin cannot be used while the Kernel program is running (during in-circuit debug operations).
