SnapCPU™ Hobbiest Versions

Basic, enhanced or advanced boards for the do-it-yourself types...

Basic SnapCPU™ with flashing LED demo (mode 2). Each pin flashes at a 2x multiple of the previous simulating a binary counter which would be visible with the LEDs connected.   Advanced SnapCPU™ controlled tune playback demo (mode 6). Pre-loaded tune plays in the background from Snap04 and can be paused and restarted by the buttons connected to Snap01 and Snap02. The same circuit can also be used with the mode 2 demo.

Built-in Modes:

The SnapCPU is delivered pre-programmed with a utility that provides gives you power-on access to a number of operating modes. Modes are selected by holding the onboard buttons during power-up (the selected mode is the saved for use until changed by the user). This utility is overwritten when you write your own applications, but source code is included so you can re-install it at anytime. Below are the 6 modes built into the Advanced unit.

  • Mode 1: all snap connections are inputs, read and their "value"sent to a PC running KodeKLIX for monitoring.
  • Mode 2: Snaps 01 and 02 act as inputs, if each value goes high then a different sound effect is played to Snap04.
  • Mode 3: all snap connections are outputs, toggling such that the rate of 02 is twice that of 01, and 04 twice that of 02. Pressing one of the onboard buttons will change the rate the outputs are toggled (speeding them up for each progressive button).
  • Mode 4: snaps 01, 02, and 04 toggle when each button A, B and D is respectively pressed. button R acts to reset all snaps to off, whilst button L sets all to on.
  • Mode 5: each snap operates differently. Snap01 is an analog input, reporting to the PC datalink. Snap02 toggles Snap04 whilst pressed. Snap04 is of course an output.
  • Mode 6: Snap04 plays a tune in the background unless paused by connecting Snap01 high (the +ve terminal). It is restarted by connecting Snap02 to high.

The Experienced variant with the 14M2 processor only has modes 1-4. The Basic variant defaults to mode 1, but switches to mode 3 when the A button is pressed (it resets at SnapCPU™ powerdown).

PICAXE powered SnapCPU