Jumper & Connector Descriptions

•J1, J2: LCD LED Backlight Polarity: If J1 and J2 is set in position 1-2, then LCD pin15 is connected to +5V and pin16 is connected to GND. If J1 and J2 is set in position 2-3 then pin15 is connected to GND and pin16 is connected to +5V. Default set in position 1-2.

•J7: Trace Port Enable: J7 is set to enable pins P1.25:16 to operate as ETM Trace port after reset. Default not set.

•J8: Debug Port Enable: J8 is set to enable pins P1.31:26 to operate as a JTAG Debug port after reset. Default is set.

•J9: Debug Mode: J9 selects whether iSYSTEM on-board integrated USB-JTAG debugger is used or an external debug tool. Default set in position 1-2.*

•J10: RTC Power Supply Selector: J10 connects Vbat pin of LPC2138 to the main 3.3V.

•P11: RTC Power supply: PCB terminal providing connection for battery. When battery power supply applied to P11 is used, J10 must be open.

•P12: Manufacturing purpose connections

•P13: Analog Output: P13 is analog output from OP amplifier, which connects to output of the DA converter.

•J15: User LEDs Enable: enables the LED driver connecting the on-board LEDs to GPIO P0.4 – P0.7.

•J16: User Buttons Enable: enables buttons driver connecting the on-board buttons to GPIO P0.12 – P0.15. Pushing the button generates a low signal. If J16 is set, the CPU will not start in Boot-loader mode (see J25 description).

•J17: LCD Enable Signal: connects GPIO P0.21 to the LCD enable pin.

•J18: LCD R/W Signal: connects GPIO P0.22 to the LCD R/W pin.

•J19: Analog Output Enable: connects DA converter output (GPIO P0.25) to the OP amplifier.

•J20: Analog Input Enable: connects the TRIM potentiometer to the analog input AD0.0 (GPIO P0.27).

•P21: 16 Pin LCD Connector: see connectors

•J22: LCD LED Backlight Enable: J22 is set to turn on LCD backlight.

•J25 (bottom side): Startup mode (populated on the bottom side of the target board): J25 connects either a pull-up (USER mode) or a pull-down (BOOT-loader mode) to P0.14. Default set in position USER (User mode). J16 must be removed when setting J25 in position BOOT, otherwise J25 setting is not effective.

*Jumper pin 1 is marked with a white square on the ITLPC2138 PCB. If pin 1 cannot be located directly from the ITLPC2138, please use Figure 2 for assistance.

Note: Don’t change jumper settings while the target board is supplied with power!

6/13