High resolution barometric pressure sensor

Controller connections

LCD  Direction  LPC2103  Signal
EN     <---     P0.17    Enable (10 kOhm pull-up to 5 V on controller)
RW     <---     P0.18    Direction of data bus						   
RS     <---     P0.19    Data/instruction select
D4     <-->     P0.20    Data 0
D5     <-->     P0.21	  Data 1
D6     <-->     P0.22	  Data 2
D7     <-->     P0.23	  Data 3

HP03D      Direction  LPC2103        Signal
1 - VSS               -              GND
2 - VDD               -              +3.3 V
3 - MCLK     <---     P0.7 - MAT2.0  32768 Hz
4 - XCLR     <---     P0.4 - PIO     Reset (Active low, high during A/D operation)
5 - SDA      <-->     P0.3 - SDA0    I2C data (10 kOhm pull-up to 3.3 V)
6 - SCLK     <---     P0.2 - SCL0    I2C clock (10 kOhm pull-up to 3.3 V)

Parts used

Suitable parts can be found at Futurlec

ET-BASE ARM2103 controller

• CPU NXP LPC2103
• RAM 8192 bytes
• FLASH 32768 bytes
• Clock rate 59 MHz
• Supply voltage 5 V

LCD display Optrex 20434

• 20 x 4 characters
• 4 bit bus
• Supply voltage 5 V
• Supply current 3 mA

Pressure sensor HP03D

• Pressure range 300-1100 hPa
• 16 bit A/D
• I²C Serial interface
• Accurate to 0.5 hPa
• Supply voltage: 2.2 - 3.6 V (provided by controller)
• Supply current 500 uA during A/D conversion