The Cowlacious CAR/P audio board can be started by the Prop-1/2/SX by using the OUTx terminals. Using the trigger wire supplied by Cowlacious, connect the white wire to the OUTx terminal of your choice (I use OUT5) and the black wire to the GND terminal. If you are providing power to the CAR/P through the Prop-1/2/SX V+ and GND terminals the the black trigger wire need not be connected (I folded it back and covered it with a piece of electrical tape.
The Trigger input on the CAP board is designed to mat switches and buttons hence it is debounced, and after a bit of testing I have found that to start reliably you need to pull the input low (through the OUTx terminal) for at least 250 milliseconds.
Here's my little Prop-1 demo:
' =========================================================================
'
' File...... CAP_Audio.BS1
' Purpose...
' Author.... Jon Williams, EFX-TEK
' Copyright (c) 2008 EFX-TEK
' Some Rights Reserved
' -- see http://creativecommons.org/licenses/by/3.0/
' E-mail.... jwilliams@efx-tek.com
' Started...
' Updated... 01 OCT 2008
'
' {$STAMP BS1}
' {$PBASIC 1.0}
'
' =========================================================================
' -----[ Program Description ]---------------------------------------------
' -----[ Revision History ]------------------------------------------------
' -----[ I/O Definitions ]-------------------------------------------------
SYMBOL Sio = 7 ' SETUP = out; no ULN
SYMBOL Trigger = PIN6 ' SETUP = DN
SYMBOL CapAudio = PIN5 ' white->OUT5, black->GND
' -----[ Constants ]-------------------------------------------------------
SYMBOL IsOn = 1 ' for active-high in/out
SYMBOL IsOff = 0
SYMBOL Baud = OT2400
' -----[ Variables ]-------------------------------------------------------
SYMBOL timer = B2
' -----[ Initialization ]--------------------------------------------------
Reset:
PINS = %00000000 ' clear all outputs
DIRS = %00111111 ' make P0-P5 outputs
PAUSE 1000 ' let CAP initialize
' -----[ Program Code ]----------------------------------------------------
Main:
DEBUG "Ready. "
timer = 0 ' reset timer
Check_Trigger:
PAUSE 5 ' loop pad
timer = timer + 5 * Trigger ' update timer
IF timer < 100 THEN Check_Trigger ' wait for 0.1 sec input
DEBUG "Playing...", CR
GOSUB CAP_Start
PAUSE 2000 ' adjust for sound
GOTO Main
' -----[ Subroutines ]-----------------------------------------------------
CAP_Start:
CapAudio = IsOn ' pull OUTx low
PAUSE 250 ' hold for CAP debounce
CapAudio = IsOff ' release OUTx
RETURN
' -------------------------------------------------------------------------
' -----[ User Data ]-------------------------------------------------------