The uM-FPU V2 is a 32-bit floating point coprocessor that can be easily interfaced with the BASIC Stamp^® (BS2, BS2e, BS2sx, BS2p24, BS2p40, BS2pe, BS2px), Javelin Stamp, and SX microcontroller to provide support for 32-bit IEEE 754 floating point operations and long integer operations. The uM-FPU V2 is easy to connect, and requires only two pins on the BASIC Stamp, Javelin Stamp, or SX microcontroller.  For both microcontrollers, the only external component required for operation is a protection resistor on the bidirectional data line.

uM-FPU V2 features for the BASIC Stamp Microcontroller

• 8-pin integrated circuit.
• Bi-directional serial interface requires only two wires for connection.
• Sixteen 32-bit general purpose registers for storing floating point or long integer values.
• Five 32-bit temporary registers with support for nested calculations (i.e. parenthesis)
  • Floating Point Operations
  • Set, Add, Subtract, Multiply, Divide
  • Sqrt, Log, Log10, Exp, Exp10, Power, Root
  • Sin, Cos, Tan
  • Asin, Acos, Atan, Atan2
  • Floor, Ceil, Round, Min, Max, Fraction
  • Negate, Abs, Inverse
  • Convert Radians to Degrees
  • Convert Degrees to Radians
  • Compare, Status
• Long Integer Operations
  • Set, Add, Subtract, Multiply, Divide, Unsigned Divide
  • Negate, Abs
  • Compare, Unsigned Compare, Status
• Conversion Functions
  • Convert 8-bit and 16-bit integers to floating point
  • Convert 8-bit and 16-bit integers to long integer
  • Convert long integer to floating point
  • Convert floating point to long integer
  • Convert floating point to ASCII
  • Convert floating point to formatted ASCII
  • Convert long integer to ASCII
  • Convert long integer to formatted ASCII
  • Convert ASCII to floating point
  • Convert ASCII to long integer
  • Full set of BASIC Stamp support routines provided for easy implementation.

Connecting the uM-FPU V2 to the BASIC Stamp module
The uM-FPU V2 requires just two pins for interfacing to the BASIC Stamp module. The communication is implemented using a bidirectional serial interface that requires a clock pin and a data pin. The default setting for these pins are:

• FpuClock PIN 15
• FpuData PIN 14

The settings for these pins can be changed to suit your application. The support routines assume that the uM-FPU V2 chip is always selected, so the FpuClock and FpuData pins should not be used for other connections as this will likely result in loss of synchronization between the BASIC Stamp module and the uM-FPU V2 coprocessor. To connect the device to the Javelin Stamp module, download the documentation below.

Downloads and Resources:
uM-FPU V2 Documentation for BASIC Stamp 2 modules (.pdf)
uM-FPU V2 Documentation for Javelin Stamp modules (.pdf)
uM-FPU V2 Documentation for SX and SX/B modules (.pdf)
uM-FPU V2 Instruction Set (.pdf)
uM-FPU V2 Datasheet (.pdf)
Software Download Page - BASIC Stamp 2 Modules (Off Site)
Software Download Page - Javelin Stamp Modules (Off Site)
Software Download Page - SX and SX/B Microcontrollers (Off Site)