Digi BL1800 user manual Existing

The thermistor has a nominal room-temperature resistance of about 10 kΩ, which drops to about

6kΩ at 40°C. Once you solder the thermistor onto the RT1 pads (see Figure B-5) on the Prototyping Board, the A/D converter readings on AD0 will change with temperature.

If the 10 kΩ potentiometer is removed, the change in A/D converter readings with temperature will be larger.

	LS1				R3
	Buzzer				3
					2
COIL()-	R1				+
					1
		HV0	+RAWPOT PE4			GND AD0
	JP2				RT1
		BZR VCC	K	AD0	PD0
				DS1		S1

10kW Potentiometer

Thermistor

The LEDs can be mounted in positions DS5–DS8, shown in Figure B-6,to display the complete status for Parallel Port A.

The serial cable included in the parts bag can be used to connect the Jackrabbit’s RS-232 outputs from header J1 on the Prototyping Board to an available PC serial port.

Unlike the CMOS-level signals on header J3, the programming port on the Jackrabbit board, the sig- nals on header J1 on the Prototyping Board are full RS-232 level signals without needing the CMOS to RS-232 converter that is present in the program- ming cable. The RS-232 level signals are processed via the MAX232 transceiver chip, U4, on the Jack- rabbit board to Serial Ports B and C of the Rabbit 2000. The CMOS-level signals on the program- ming port are connected to Serial Port A.

Figure B-5. Thermistor and

Potentiometer Locations

		}	DS1	S1
Existing			DS2
LEDs	}		DS3	S2
			DS4	S3
			DS5
Add			DS6
Dev Kit				S4
			DS8 DS7 DS9
LEDs				PWR

Figure B-6. LED Location

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