C M L - 1 2 C 3 2
J U L Y
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OPTIONS and JUMPERS
MEM_EN
The MEM_EN option jumper is installed by default and enables access to the external SRAM
memory when the MCU is configured for expanded mode operation. Removing the MEM_EN
option jumper disables external memory access.
MODE
The MODE option jumper is not installed on the CML-12C32 board and is hard connected by
circuit copper trace for Single-chip Mode operation of the CPU. MODA and MODB signals are
terminated by this option. Single Chip Mode operation is selected by default because the MCU
internal flash memory provides the only nonvolatile program memory on the board. All other
Modes can be enabled under software control from this mode of operation.
The MODE option jumper may be installed by the user by cutting the circuit trace and installing
a 2-position header with a shunt jumper. With the shunt jumper removed, the Reset mode will
then be Normal Expanded Wide. External non-volatile memory must be added to support this
functionality.
NO_AUTO
The NO_AUTO jumper prevents the MCU from executing program code at start up. Enable
automatic program execution by removing this jumper. To use the auto-start feature, the cor-
rect reset vector must be loaded to point to the location of program code.
RANGE
The CML-12C32 board provides a 20-turn, 10 k ? , precision, potentiometer (POT) with adjust-
able range for use in circuit prototyping. The RANGE jumper selection of output range. In-
stalling the option jumper provides the full range output from the POT from GND to V DD . Re-
moving the option jumper places a 10k ? resistor in series with the POT limiting output from
GND to ? V DD .
JP1 POT_OUT_SEL
The JP1 option jumper selects where the destination of the potentiometer. The output of the
POT may be routed to a MCU analog port input (PAD7/AN7) or to the BUS_PORT header for
use on prototyping area.
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