Honeywell HMR3100 User Manual

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HMR3100
 
   
 
 
SENSOR PRODUCTS 
 
Solid State Electronics Center 
 www.magneticsensors.com  (800) 323-8295 • Page 3 
converters (ADC) onboard a microcontroller (
µC) integrated circuit. The microcontroller integrated circuit periodically 
samples the amplified sensor voltages, performs the offset corrections, and computes the heading. This 
microcontroller also performs the external serial data interface and other housekeeping functions such as the 
calibration routine.  
 
The power supply for the HMR3100 circuit board is to be about a +3 to +5 volt range allowing the user to provide a 
single lithium battery to logic level supply voltages. The power supply architecture is a single ground system for single 
ended supply sources (+ and ground return). 
 
Note the “North Arrow” printed on the HMR3100  circuit board top side. This is the mechanical reference for product 
alignment purposes. When placed on the development kit’s RS-232 motherboard assembly, this arrow also points 
toward the 9-volt batterypin block on the motherboard (away from the RJ-11 jack). 
 
Pin Configuration 
 
Pin Number 
Pin Name 
Description 
VCC 
Power Supply Input  
2 NC 
No 
Connection 
RTS 
Ready To Send Input 
4 NC 
No 
Connection 
TXD 
Transmit Data Output 
RXD 
Receive Data Input 
GND 
Power and Signal Ground 
8 NC 
No 
Connection 
 
 
The HMR3100 board is 0.77” on each side with eight pins in groups of four spaced at 0.6” apart in wide-DIP format. 
Seated height is approximately 0.275”. Pin 1 is the upper right pin in Figure 1 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 1 
HMR3100 Dimensions