Distributor of NXP Semiconductors: Excellent Integrated System Limited
Datasheet of DEMO908JL16 - BOARD DEMO FOR MC908JL16
Contact us: [email protected] Website: www.integrated-circuit.com
Operating Modes
Page 16
i
Note: all of the HC08 family devices feature a monitor code resident in
ROM which, through a serial communication line, allows the programming
and the in-circuit debugging of the user application. The monitor code is
executed in “monitor mode”; the user application is executed in “user
mode”. To enter the monitor mode some microcontroller lines must be
properly driver (for further details please refer to the microcontroller’s data
sheet).
The USB TO MON08 INTERFACE section groups the circuitry needed to
generate the required signals to enter the monitor mode and
communicate with the host PC’s USB port. In particular, to enter the
monitor mode, the “USB TO MON08 INTERFACE” circuitry:
Generates a high-level voltage signal (VTST) on the IRQ pin of the
microcontroller;
Generates a high-level voltage and an appropriate reset signal on
the RST pin of the microcontroller;
Drives the microcontroller’s VDD on and off, with specific timing, in
order to enter the monitor mode;
Handles a single-wire, bi-directional serial communication line on a
specific pin of the microcontroller.
To work in host mode (using the built-in USB to MON08 interface):
Make sure that all of the jumpers in the “USB to MON08” section are inserted.
Make sure that the “POWER SEL1” jumper is in the “USB” position.
Connect the host PC to the board through the provided USB cable.
19 / 33
19 / 33