Prop memory talk?

Comments

• mctrivia Posts: 3,772

  2009-12-01 22:12 edited 2009-12-01 22:12

  Because it is not needed for boot. Solder a pull up to the other wire and you are good.
  
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• Zap-o Posts: 452

  2009-12-01 22:18 edited 2009-12-01 22:18

  mctrivia
  Are you sure. I think that I tried this and it would not program to eeprom. Hum - I will try it again.
• mctrivia Posts: 3,772

  2009-12-01 22:24 edited 2009-12-01 22:24

  Make sure the 2 devices do not use same address. It is safe to have a 10k pull up on each line.
  
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• Phil Pilgrim (PhiPi) Posts: 23,514

  2009-12-01 23:44 edited 2009-12-01 23:44

  A pullup on SCL is only necessary on multimaster busses or with slave devices that implement clock stretching. Otherwise, it's okay to drive SCL both high and low, and no pullup is required.
  
  -Phil
• Graham Stabler Posts: 2,510

  2009-12-01 23:45 edited 2009-12-01 23:45

  If the propeller is always the master then no pull up is needed on the clock line (SCL) because the prop can drive it high and low. One is needed on the data line (SDA) as the I2C device will only pull the line low.
  
  A 10k pull up on the clock will make no difference to the props ability to drive the line so it should not have affected the eeprom operation.
  
  Graham
• Cluso99 Posts: 18,069

  2009-12-02 02:02 edited 2009-12-02 02:02

  I always put 10K on both. I usually use the SCL to drive other things as well.
  However, the boot code of the prop makes the SCL line an output so the pullup is not required.
  
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