27220 Parallax Inc, 27220 Datasheet - Page 75

• Manufacturer Part Number: 27220
• Description: BOOK STAMPWORKS
• Manufacturer: Parallax Inc

Specifications of 27220

• Accessory Type: Booklet
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• For Use With/related Products: StampWorks
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Not applicable / Not applicable

Show_Die:
' -----[ Subroutines ]-----------------------------------------------------
Tumble_Die:
Behind the Scenes
This program borrows heavily from what we’ve already done and should be easy to
understand. What we’ve done here is added a bit of programming creativity to make
a very simple program visually interesting.
Of note is the Tumble_Die subroutine which actually does quite a lot of work. The
first thing this routine does is shake the random number generator. Since the main
loop will call this subroutine about every five milliseconds, it’s getting a lot of shaking
and should give us nice random results.
From the random number the die value is created. Remember what we learned
about the modulus operator: it will always return a value between zero and the
divisor. Since there are six faces on a die, we divide the random value by six and
take the modulus; this gives us zero to five. Adding one “fixes” the value so it’s
between one and six.
Finally, this same subroutine is responsible for updating the animated “bug” used to
indicate the die being shaken. If we updated the frame through every pass of the
subroutine the display would look more like a flickering zero than an animation – we
need to slow things down, perhaps updating the animation every tenth time through
(which would give us a bit more than 50 ms per frame). This is accomplished by
using doSpin as a timer. This value gets incremented then divided by 10 (with //)
on every pass; when the modulus result is zero it’s time to update the animation
READ (Digit0 + dieVal), Segs
PAUSE 3000
GOTO Main
RANDOM rndVal
dieVal = (rndVal // 6) + 1
doSpin = (doSpin + 1) // 10
IF (doSpin = 0) THEN
ENDIF
RETURN
spinPos = (spinPos + 1) // BugLen
READ (Bug0 + spinPos), Segs
' transfer die to segments
' hold for viewing
' start again
' stir random value
' get die val, 1 - 6
' update spin timer
' time for update
' yes, point to next pos
' output to segments