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One pin short — Parallax Forums

One pin short

ArchiverArchiver Posts: 46,084
edited 2004-05-09 16:42 in General Discussion
I'm building a project using the BS2P40 (R/C submarine) building everything including the RF link. I have used all 32 pins on the hand held side of the link. One of the devices in the hand held unit is the Quadravox sound module from Parallax. I thought (incorrectly it turns out) that I could skip the reset line on the QV board. The QV board works fine the first time I run the program and play a file, however the second time I try to play a sound the QV board won't play along. If I power down and power up again it works, also if I manually reset the QV board with a clip lead then play a sound it works fine..

Here's my question: Can I use one of the pins I use for input most of the time and make it do double duty and on occasion reset the QV board?? If so how do I go about making this bit of magic work?? My first thoughts on a candidate is the "GO" button, a momentary (N/O) that gets used VERY seldom realitive to the sprgram speed. How do I "wire OR" this pin?? Any traps to avoid using a pin for double duty??

Here are my logical pin assignments:

'{$STAMP BS2p}
'Pin assignments for the control unit

'Pin # Use
'

' MAIN I/O PIN

'0 I2C SDA (DS1307 pin 5)
'1 I2C SCL (DS1307 pin 6)
'2 RTC SQW (DS1307 pin 7)
'3 BCD DATA pin (74LS165 pin 9)<
Thumb wheel data
'4 BCD DATA clock (74LS165 pin 2)
'5 BCD DATA load (74LS165 pin 1)
'6 LED DATA pin (74HC595 pin 14<
System status LED display
'7 LED DATA clock (74HC595 pin 11)
'8 LED DATA latch (74HC595 pin 12)
'9 Radio TX DATA<----430 Mhz 5, watt radio module
'10 Radio RX DATA
'11 Radio CTS
'12 Radio RTS
'13 LTC1298 #2 Chip select<
Reads 3 POTS for control of speed, direction and dive planes
'14 LTC1298 #2 Clock
'15 LTC1298 #2 DATA

' AUX I/O PINS

'X0 Forward Ballast tank Blow
'X1 Forward Ballast tank vent
'X2 Aft ballast tank blow
'X3 Aft ballast tank vent
'X4 Dive tank blow
'X5 Dive tank vent
'X6 Scope Up
'X7 Scope Down
'X8 LTC1298 #1 Chip select
'X9 LTC1298 #1 Clock
'X10 LTC1298 #1 DATA (bi-directional)
'X11 LCD display (16624 baud mode)<----Scott Edwards 4 X 16 backlit LCD display
'X12 Go button (input to Stamp) <
Maybe use also as a reset pin for the quadravox??
'X13 Quadravox Rx DATA (n,8,1 true)<Sound board for things like, "Dive, Dive" etc
'X14 QuadraVox Tx DATA
'X15 QuadraVox busy pin

Thanks

Mike B.

[noparse][[/noparse]Non-text portions of this message have been removed]

Comments

  • ArchiverArchiver Posts: 46,084
    edited 2004-05-09 14:37
    Hi Mike,

    If I'm not mistaking you could tie together the Clck and the Data
    lines of the two LTC1298 chips. The still seperate CS lines then
    determine which chip is actually used.

    This would free two pins.

    Regards,

    Klaus


    --- In basicstamps@yahoogroups.com, "Mike Blier" <w4fej@b...> wrote:
    > I'm building a project using the BS2P40 (R/C submarine) building
    everything including the RF link. I have used all 32 pins on the
    hand held side of the link. One of the devices in the hand held unit
    is the Quadravox sound module from Parallax. I thought (incorrectly
    it turns out) that I could skip the reset line on the QV board. The
    QV board works fine the first time I run the program and play a file,
    however the second time I try to play a sound the QV board won't play
    along. If I power down and power up again it works, also if I
    manually reset the QV board with a clip lead then play a sound it
    works fine..
    >
    > Here's my question: Can I use one of the pins I use for input
    most of the time and make it do double duty and on occasion reset the
    QV board?? If so how do I go about making this bit of magic work??
    My first thoughts on a candidate is the "GO" button, a momentary
    (N/O) that gets used VERY seldom realitive to the sprgram speed. How
    do I "wire OR" this pin?? Any traps to avoid using a pin for double
    duty??
    >
    > Here are my logical pin assignments:
    >
    > '{$STAMP BS2p}
    > 'Pin assignments for the control unit
    >
    > 'Pin # Use
    > '

    > ' MAIN I/O PIN
    >
    > '0 I2C SDA (DS1307 pin 5)
    > '1 I2C SCL (DS1307 pin 6)
    > '2 RTC SQW (DS1307 pin 7)
    > '3 BCD DATA pin (74LS165 pin 9)<
    Thumb wheel data
    > '4 BCD DATA clock (74LS165 pin 2)
    > '5 BCD DATA load (74LS165 pin 1)
    > '6 LED DATA pin (74HC595 pin 14<
    System status LED display
    > '7 LED DATA clock (74HC595 pin 11)
    > '8 LED DATA latch (74HC595 pin 12)
    > '9 Radio TX DATA<----430 Mhz 5, watt radio module
    > '10 Radio RX DATA
    > '11 Radio CTS
    > '12 Radio RTS
    > '13 LTC1298 #2 Chip select<
    Reads 3 POTS for control of
    speed, direction and dive planes
    > '14 LTC1298 #2 Clock
    > '15 LTC1298 #2 DATA
    >
    > ' AUX I/O PINS
    >
    > 'X0 Forward Ballast tank Blow
    > 'X1 Forward Ballast tank vent
    > 'X2 Aft ballast tank blow
    > 'X3 Aft ballast tank vent
    > 'X4 Dive tank blow
    > 'X5 Dive tank vent
    > 'X6 Scope Up
    > 'X7 Scope Down
    > 'X8 LTC1298 #1 Chip select
    > 'X9 LTC1298 #1 Clock
    > 'X10 LTC1298 #1 DATA (bi-directional)
    > 'X11 LCD display (16624 baud mode)<----Scott Edwards 4 X 16
    backlit LCD display
    > 'X12 Go button (input to Stamp) <
    Maybe use also as a
    reset pin for the quadravox??
    > 'X13 Quadravox Rx DATA (n,8,1 true)<Sound board for things
    like, "Dive, Dive" etc
    > 'X14 QuadraVox Tx DATA
    > 'X15 QuadraVox busy pin
    >
    > Thanks
    >
    > Mike B.
    >
    > [noparse][[/noparse]Non-text portions of this message have been removed]
  • ArchiverArchiver Posts: 46,084
    edited 2004-05-09 16:42
    --- In basicstamps@yahoogroups.com, "klausdejong" <klausdejong@x>
    wrote:
    > Hi Mike,
    >
    > If I'm not mistaking you could tie together the Clck and the Data
    > lines of the two LTC1298 chips. The still seperate CS lines then
    > determine which chip is actually used.
    >
    > This would free two pins.
    >
    > Regards,
    >
    > Klaus

    looks like the DS1307 is using 3 pins also.
    check the data sheets on using it as a 2 wire device.


    But, it seems like you might be able free up a few pins elswhere.

    Since you probably have the DS1307 embeded in your board, you cannot
    swap it out for a DS1302. That would have offered the serial lines
    of the LTC1298 and then needed only one pin for the chip select.

    Dave




    >
    >
    > --- In basicstamps@yahoogroups.com, "Mike Blier" <w4fej@b...> wrote:
    > > I'm building a project using the BS2P40 (R/C submarine) building
    > everything including the RF link. I have used all 32 pins on the
    > hand held side of the link. One of the devices in the hand held
    unit
    > is the Quadravox sound module from Parallax. I thought
    (incorrectly
    > it turns out) that I could skip the reset line on the QV board.
    The
    > QV board works fine the first time I run the program and play a
    file,
    > however the second time I try to play a sound the QV board won't
    play
    > along. If I power down and power up again it works, also if I
    > manually reset the QV board with a clip lead then play a sound it
    > works fine..
    > >
    > > Here's my question: Can I use one of the pins I use for input
    > most of the time and make it do double duty and on occasion reset
    the
    > QV board?? If so how do I go about making this bit of magic
    work??
    > My first thoughts on a candidate is the "GO" button, a momentary
    > (N/O) that gets used VERY seldom realitive to the sprgram speed.
    How
    > do I "wire OR" this pin?? Any traps to avoid using a pin for
    double
    > duty??
    > >
    > > Here are my logical pin assignments:
    > >
    > > '{$STAMP BS2p}
    > > 'Pin assignments for the control unit
    > >
    > > 'Pin # Use
    > > '

    > > ' MAIN I/O PIN
    > >
    > > '0 I2C SDA (DS1307 pin 5)
    > > '1 I2C SCL (DS1307 pin 6)
    > > '2 RTC SQW (DS1307 pin 7)
    > > '3 BCD DATA pin (74LS165 pin 9)<
    Thumb wheel data
    > > '4 BCD DATA clock (74LS165 pin 2)
    > > '5 BCD DATA load (74LS165 pin 1)
    > > '6 LED DATA pin (74HC595 pin 14<
    System status LED
    display
    > > '7 LED DATA clock (74HC595 pin 11)
    > > '8 LED DATA latch (74HC595 pin 12)
    > > '9 Radio TX DATA<----430 Mhz 5, watt radio module
    > > '10 Radio RX DATA
    > > '11 Radio CTS
    > > '12 Radio RTS
    > > '13 LTC1298 #2 Chip select<
    Reads 3 POTS for control of
    > speed, direction and dive planes
    > > '14 LTC1298 #2 Clock
    > > '15 LTC1298 #2 DATA
    > >
    > > ' AUX I/O PINS
    > >
    > > 'X0 Forward Ballast tank Blow
    > > 'X1 Forward Ballast tank vent
    > > 'X2 Aft ballast tank blow
    > > 'X3 Aft ballast tank vent
    > > 'X4 Dive tank blow
    > > 'X5 Dive tank vent
    > > 'X6 Scope Up
    > > 'X7 Scope Down
    > > 'X8 LTC1298 #1 Chip select
    > > 'X9 LTC1298 #1 Clock
    > > 'X10 LTC1298 #1 DATA (bi-directional)
    > > 'X11 LCD display (16624 baud mode)<----Scott Edwards 4 X 16
    > backlit LCD display
    > > 'X12 Go button (input to Stamp) <
    Maybe use also as
    a
    > reset pin for the quadravox??
    > > 'X13 Quadravox Rx DATA (n,8,1 true)<Sound board for things
    > like, "Dive, Dive" etc
    > > 'X14 QuadraVox Tx DATA
    > > 'X15 QuadraVox busy pin
    > >
    > > Thanks
    > >
    > > Mike B.
    > >
    > > [noparse][[/noparse]Non-text portions of this message have been removed]
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