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VTI Pressure sensor Demo — Parallax Forums

VTI Pressure sensor Demo

James LongJames Long Posts: 1,181
edited 2010-03-05 00:49 in Accessories
Ok....I have a gripe....which for Parallax is uncommon.

The source code for the VTI is a bin file.....which the Propeller tool can load, but the code is not available.

I would like to have the code for my own uses.

Would it be possible to get the spin/asm file of the demo?

James L

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James L
Partner/Designer

Lil Brother SMT Assembly Services

Please note: Due to economic conditions the light at the end of the tunnel will be turned off until further notice. Thanks for your understanding.

Comments

  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2009-10-09 17:05
    James, this should be taken care of by Monday...that was my mistake.· It is not even the correct demo code.· My apologies.

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    Chris Savage

    Parallax Engineering
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    ·
  • James LongJames Long Posts: 1,181
    edited 2009-10-09 17:51
    Chris Savage (Parallax) said...
    James, this should be taken care of by Monday...that was my mistake. It is not even the correct demo code. My apologies.

    OK,

    I'll let you slide this time....... smilewinkgrin.gif

    I understand these things happen.......

    James L

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    James L
    Partner/Designer

    Lil Brother SMT Assembly Services

    Please note: Due to economic conditions the light at the end of the tunnel will be turned off until further notice. Thanks for your understanding.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2009-10-09 18:00
    James, thanks for understanding...I have been working on code for four products at once. Somewhere along the way the lines get blurred sometimes.

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    Chris Savage

    Parallax Engineering
    50 72 6F 6A 65 63 74 20 53 69 74 65
    ·
  • James LongJames Long Posts: 1,181
    edited 2009-10-09 18:12
    Chris Savage (Parallax) said...
    James, thanks for understanding...I have been working on code for four products at once. Somewhere along the way the lines get blurred sometimes.

    Well...to be honest....I can't gripe too much. I didn't buy my sensor from Parallax.........so I have no room to point fingers.

    I was just going to take a peek at how you guys did the code.

    James L

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    James L
    Partner/Designer

    Lil Brother SMT Assembly Services

    Please note: Due to economic conditions the light at the end of the tunnel will be turned off until further notice. Thanks for your understanding.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2009-10-09 19:37
    Nonetheless, it is in error...our example/demo code is always available to our customers in source format. I just have to pay more attention to what package I ask to be published on the web. =)

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    Chris Savage

    Parallax Engineering
    50 72 6F 6A 65 63 74 20 53 69 74 65
    ·
  • phil kennyphil kenny Posts: 233
    edited 2009-10-15 18:20
    I'm in hope when the Parallax demo code is finally released in source format that
    it will also include how to access and display the temperature monitoring feature
    of the VTI SPC1000 and not just the pressure readings.

    Source code for the Basic Stamp would be very desirable as well.

    phil

    Post Edited (phil kenny) : 10/15/2009 6:25:39 PM GMT
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2009-10-15 21:08
    Phil,

    I just responded in another thread that BASIC Stamp code would be available as well as updated Propeller code. I plan on including the temperature as well. I apologize for not meeting my timeline. I am trying to allocate some time to Propeller objects that need to be done. I am thinking next week will be possible. I will follow up on these threads as soon as I have something though. Rest assured.

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    Chris Savage

    Parallax Engineering
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    ·
  • kberckkberck Posts: 10
    edited 2009-10-31 20:33
    Appreciate it Chris, we know they are working you hard! [noparse]:)[/noparse] Thanks in advance!
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2009-11-02 22:52
    Okay, so as an update there were a few hang-ups I hit on the code...These are due to short-comings of my own which I will be addressing with our master programmer. Seems I need to get caught up to date on some stuff. So bear with me while I further my Propeller Education a bit and wrap these objects. The BASIC Stamp code just needs a schematic on the connections since it's a 3.3V --> 5V connection. Take care.

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    Chris Savage

    Parallax Engineering
    50 72 6F 6A 65 63 74 20 53 69 74 65
    ·
  • StroudljStroudlj Posts: 2
    edited 2009-11-06 16:45
    Chris, you stated that "The BASIC Stamp code just needs a schematic", does that mean that you have a .pdf for it, just waiting on the schematic or are you saying that all the BASIC Stamp users just need the schematic and not code?

    Not sure if I am comunicating what I am asking... If the .pdf for the BASIC stamp users is complete, could you post a link to it?

    Larry Stroud
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2009-11-08 07:45
    Larry, sorry for the delay...I have actualy been brushing up on some SPIN and PASM myself recently. We have BASIC Stamp code, but you cannot connect the sensor directly to the BASIC Stamp as it is 3.3V and the BASIC Stamp module is a 5V device. I have been working on a schematic that will use readily accessible parts that the average customer can use for the interface so they don't need a specialized interface IC. I will have something soon. Right now I want to wrap the SPIN code but I needed to get caught up as I have been working on so much hardware I haven't really done much programming in a while and found myself a little rusty. =) It happens to the best of us.

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    Chris Savage

    Parallax Engineering
    50 72 6F 6A 65 63 74 20 53 69 74 65
    ·
  • JaimeJaime Posts: 16
    edited 2010-01-26 01:44
    Chris: I am also very interested in the code to interface this sensor with the Basic Stamp2. If you· have an advance with the code that you could post would be very useful, in the meanwhile I could find out how to develop the hardware to connect the components. If you have something pass it on.. I understand the hard·work you have been doing on it.. Thanks a lot Chris..·
  • WildatheartWildatheart Posts: 195
    edited 2010-01-26 04:24
    Chris, I too would like to have your proposed interface diagrams for the BS2 as well as the experimental source code. I'm interested in using the sensor to monitor the cabin pressure of my submersible.
  • JDJD Posts: 570
    edited 2010-01-28 01:25
    Wildatheart,

    My apologies, it turns out the firmware for that module is not available to the public; so only the binary files can be used

    I hope this helps,

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    Respectfully,


    Joshua Donelson
    www.parallax.com

    Post Edited (Joshua Donelson (Parallax)) : 1/29/2010 7:42:53 PM GMT
  • Sal AmmoniacSal Ammoniac Posts: 213
    edited 2010-02-01 21:11
    Here's some Spin code that reads the sensor temperature and pressure information in a loop:

    '' SCP1000 Driver
''
'' Pin assignments (relative to 'Pin' parameter passed to SCPInit):
''
''      0   SCK  (output)
''      1   MOSI (output)
''      2   MISO (input)
''      3   CSB  (output)
''      4   DRDY (input)
''
''

CON

  SCK = 0                                               ' Clock
  MOSI = 1                                              ' Master Out, Slave In
  MISO = 2                                              ' Master In, Slave Out
  CSB = 3                                               ' Chip Select
  DRDY = 4                                              ' Device Ready


  AltCor = 1920                                         ' sealevel altitude correction (in mb * 100)                        


VAR

  long Pin
  long status
  long rawtemperature, pressureH, pressureL
  long Temperature, Pressure
  long Stack[noparse][[/noparse]64]
  byte Cog



PUB Start(PinStart) : okay

  Stop
  okay := (Cog := cognew(SCPInit(PinStart), @Stack) + 1)

PUB Stop

  if Cog
    cogstop(Cog~ - 1)

PUB Active : YesNo

  YesNo := Cog > 0

  
PUB SCPInit(PinStart)

  waitcnt(clkfreq/10 + cnt)                             ' wait 100 msec for SCP1000 to initialize
  Pin := PinStart                                       ' save starting port pin number

  dira[noparse][[/noparse]PinStart..(PinStart+DRDY)] := %11010               ' set port direction bits

  CSB_HI                                                ' set CSB high (inactive)
  SCK_LO                                                ' set SCK low

  SCPWriteRegister($3, $a)                              ' select high-precision mode
  SCPReadRegister8($1f)                                 ' dummy read of pressure register to clear DRDY
  SCPReadRegister16($20)

  SCPLoop                                               ' kick off processing


PUB SCPLoop | TempC, TempF


  repeat
    waitpeq(|< (Pin+DRDY), |< (Pin+DRDY), 0)            ' wait for DRDY to go high
    status := SCPReadRegister8($7)                      ' read status register

    rawtemperature := SCPReadRegister16($21)            ' read temperature register
    pressureH := SCPReadRegister8($1f)                  ' read pressure register (high bits)
    pressureH &= $7                                     ' only lower 3 bits are significant
    pressureL := SCPReadRegister16($20)                 ' read lower bits of pressure
    pressureL := (pressureH << 16) | pressureL          ' merge pressure halves
   
    TempC := rawtemperature * 10 / 2                    ' compute temperature in °C x 100
    TempF := TempC * 9 / 5 + 3200
 
    pressureL /= 4                                      ' convert raw pressure to mb x 100
    pressureL += AltCor
    
    Temperature := TempF
    Pressure := pressureL


PUB SCPTemp

  result := Temperature

PUB SCPPressure

  result := Pressure

  
PRI CSB_HI
  outa[noparse][[/noparse]Pin+CSB]~~                                       ' set CSB high (inactive)

PRI CSB_LO
  outa[noparse][[/noparse]Pin+CSB]~                                        ' set CSB low (active)

PRI SCK_HI
  outa[noparse][[/noparse]Pin+SCK]~~                                       ' set SCK high

PRI SCK_LO
  outa[noparse][[/noparse]Pin+SCK]~                                        ' set SCK low


PRI SCPWriteRegister(reg, value)
  reg <<= 2
  reg |= $2                                             ' set bit to indicate write

  CSB_LO                                                ' set CSB to enable sensor
  SCPSend(reg)                                          ' write register address
  SCPSend(value)                                        ' write register value
  CSB_HI                                                ' disbale chip select


PRI SCPSend(value) : rbyte | tmp, i
  tmp := value >< 8                                     ' reverse order of bits
  repeat i from 0 to 7
    SCK_LO                                              ' set SCK low
    outa[noparse][[/noparse]Pin+MOSI] := tmp & 1                           ' write bit out to sensor
    tmp >>= 1
    SCK_HI                                              ' set SCK high    
    rbyte := (rbyte << 1) | ina[noparse][[/noparse]Pin+MISO]               ' accumulate incoming data

  SCK_LO                                                ' lower SCK


PRI SCPReadRegister8(reg) : rbyte
  reg <<= 2
  reg &= $fc                                            ' clear lower two bits to indicate read command

  CSB_LO                                                ' enable sensor
  rbyte := SCPSend(reg)                                 ' send register address to sensor
  rbyte := SCPSend(0)                                   ' write dummy byte to allow sensor to respond with 8 bits of data
  CSB_HI                                                ' disable chip select 


PRI SCPReadRegister16(reg) : rword | wordH, wordL
  reg <<= 2
  reg &= $fc                                            ' clear lower two bits to indicate read command

  CSB_LO                                                ' enable sensor
  wordH := SCPSend(reg)                                 ' send register address to sensor (and ignore return value)
  wordH := SCPSend(0)                                   ' write dummy byte to allow sensor to respond with 8 bits of data (MSB)
  wordL := SCPSend(0)                                   ' write dummy byte to allow sensor to respond with 8 bits of data (LSB)
  CSB_HI
  rword := (wordH << 8) | wordL                          ' return 16 bit result
  • JDJD Posts: 570
    edited 2010-02-03 20:20
    Thank you Sal

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    Respectfully,


    Joshua Donelson
    www.parallax.com
  • JaimeJaime Posts: 16
    edited 2010-03-04 22:54
    Do any of you guys, know if there is some code example of how to interface the VTI SCP 1000 sensor to the BS2 (basic Stamp)? Your feed back will be greately appreciated.

    Best Regards

    Jaime... microwaveteach@hotmail.com
  • hover1hover1 Posts: 1,929
    edited 2010-03-05 00:49
    Yup, It's long over due.
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