Shop OBEX P1 Docs P2 Docs Learn Events
Frequency Divider Help — Parallax Forums

Frequency Divider Help

ToddTodd Posts: 3
edited 2005-09-28 02:54 in BASIC Stamp
I need to make an input selectable frequency divider and wondering if this would be a good project for the Basic Stamp and what commands I would need to use.· This would be for altering the VSS signal when changing the gear ratios in my GTO, I would need three options depending on what gear ratio I'm using, 1st would be just a 1:1 where pulses out equals pulses in, next would be where pulses out equals pulses in*.93, and last would be where pulses out equals pulses in*.85, any help would be appreciated, thanks.

Todd
·

Comments

  • Bruce BatesBruce Bates Posts: 3,045
    edited 2005-09-27 22:46
    Todd -

    Do you have any documentation or knowledge of what this "VSS signal" looks like, what the voltage is, the duration of the signal, and how often it occurs? Without that sort of information it will be difficult to tell whether any particular piece of hardware or software can use it and manipulate it within the confines of how the overall gear ratio selection system is configured.

    The more system and data information that is provided, the better the answers will probably be. Even a web site link would be fine.

    Regards,

    Bruce Bates
  • ToddTodd Posts: 3
    edited 2005-09-27 23:06
    This is just a basic square wave signal from a proximity sensor, the most the frequency input would ever be at top speed would be around 400Hz, I'm fine with all the electronics·side of it, just not with the code side, so I was wondering if a Stamp would be a good application for modifying the pulse output.

    Todd
    ·
  • Bruce BatesBruce Bates Posts: 3,045
    edited 2005-09-27 23:17
    Hi Todd -

    Seems simple enough. The PBASIC Commands that you probably want to investigate are PULSIN/PULSOUT and/or COUNT. The Parallax PBASIC Stamp Manual can be downloaded for free from here:
    http://www.parallax.com/html_pages/downloads/basicstamps/documentation_basic_stamp.asp

    Regards,

    Bruce Bates
  • ToddTodd Posts: 3
    edited 2005-09-27 23:21
    Thanks, I played with a Stamp a few years ago, but it was very simple stuff, just using it as a simple PLC basically, all digital I/O and simple logic, nothing fancy.
  • BeanBean Posts: 8,129
    edited 2005-09-28 02:54
    Todd,
    If the frequency out must be present at all times then you may need to use the SX with interrupts to accomplish the task.
    The the output does NOT have to be present at all times, then the basic stamp code will be to simply measure the incoming frequency for some period of time, adjust the value and send out the adjusted frequency for some period and repeat.
    But with the stamp while you are measuring the incoming frequency the output will be steady (either high or low).
    Bean.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "SX-Video·Module" Now available from Parallax for only $28.95

    http://www.parallax.com/detail.asp?product_id=30012
    Product web site: www.sxvm.com
    Available now... SX-Video OSD module $59.95 www.sxvm.com

    "I'm a man, but I can change, if I have to, I guess"
    Red Green
    ·
Sign In or Register to comment.