Digital Works Macros

The following links can be used to download *.dwm files, which are macros for Digital Works.  By using the "Embed Macro" button on the tool bar, you can put these devices in circuits that you are creating.

WARNING: Digital Works does not simulate the "inputs float HIGH" behavior of TTL chips.  Generally, Digital Works inputs float LOW, although even that is not reliable.

TTL Chips

(Many thanks to Dr. Pogo for creating most of these macros.)

• 74151 (8-input MUX)
• 74153 (Dual 4-input MUX)
• 7-segment display decoder like a 7447 chip (layed out to be placed directly below a Digital Works 7-segment display)
• 74138 3-bit decoder with three enable inputs
• D Flip Flop like half of a 7474 (active-low PRESET and CLEAR, unlike the D-FF on the Digital Works Tool Bar)
• JK Flip Flop like half of a 74112 (active-low PRESET and CLEAR, unlike the JK-FF on the Digital Works Tool Bar)
• 74192 (Up/Down Decade Counter)

Switches

While the "Interactive Inputs" in Digital Works can be used to control inputs as "high" or "low," sometimes you want to directly simulate a real switch that is "open" or "closed."  Digital Works does supply an "Interactive Switch" (different from an "Interactive Input"), but it doesn't have parts like resistors, which nearly always accompany such switches.  These macros fill this gap.

Each of these macros must be combined with an Interactive Switch in order to function.  The connections for the interactive switch are always on the left of the macro.  To clarify this, here is a Digital Works file illustrating use of the macros.
NOTE that due to a glitch in Digital Works, you may not see these macros when you first place them.  Scroll the window away from that area and then come back; the macro should then become visible.

• Single Pole Single Throw switches need a resistor that determines the logic value when the switch is open.  The macros RtoVcc and RtoGnd (when combined with an "Interactive Switch") simulate this functionality.
  • NOTE: An Interactive Switch is "open" when you can see the black dot, and "closed" when you can't see the black dot.
• For these Single Pole Double Throw macros, an Interactive Switch connected at the dashed lines will select which state they are in.  Unlike real SPDTs, you must use a different macro depending on which way the logic is flowing.
• SPDT1to2 connects a single input to one of two outputs.
  • WARNING: This means that the other output is floating.  Like TTL, this macro will float that output HIGH.
  • BONUS: Because the macro's "float high" behavior is reliable, this can simulate a switch with both outputs tied high by resistors, such as is appropriate for the input to a debouncing latch.
• SPDT2to1 connects one of two inputs to a single output.