SX28 Datasheet Quick Read Through

Comments

• microcontrolleruser Posts: 1,194

  2018-06-03 01:01

  
  Here's the link.
  
  https://www.parallax.com/downloads/sx20ac-and-sx28ac-datasheet
  
  This is a FINE piece of writing.It is done by Parallax.
  
  Yet it within the constraints of working with a set piece of hardware.
  
  It is copyrighted 2008.This is most excellent!
• microcontrolleruser Posts: 1,194

  2018-06-03 01:37

  
  Here's another little 'nugget of gold' in here.The internal oscillator.
  

  The internal RC mode uses an internal oscillator, so the
  device does not need any external components. At
  4 MHz, the internal oscillator provides typically +/-8%
  accuracy over the allowed temperature range. The internal
  clock frequency can be divided down to provide one of
  eight lower-frequency choices by selecting the desired
  value in the FUSE Word register. The frequency range is
  from 31.25 KHz to 4 MHz. The default operating
  frequency of the internal RC oscillator may not be 4
  MHz. This is due to the fact that the SX device requires
  trimming to obtain 4 MHz operation. The parts shipped
  out of the factory are not trimmed. The device relies on
  the programming tool provided by the third party vendors
  to support trimming.
  Figure 9-

  
  What that means to us is you can run it at 31.25 khz.That is k hertz not mega.
  
  That means you can write simple 32 count delay loops.Instead of loop upon loop to slow down a fast chip.
  
  Another tidbit is it says 'Fuse' about some of the registers.That is early terminology of micro's.
  
  Replaced by 'configuration'.
  
  
• The_Master Posts: 199

  2018-06-03 08:26

  Do you talk to yourself at the bus stop, too?
• microcontrolleruser Posts: 1,194

  2018-06-04 02:24

  
  May I resume here?
  
  Looking at the Configuration section of manual.
  
  There is no Config line like with PIC's.
  
  You do the configuration with the programmer.SX Blitz or SX Key.
  
  A little strange but I can live with it.
• Genetix Posts: 1,742

  2018-06-04 02:37

  microcontrolleruser,
  
  PIC programmers not only write to the program into program memory, but also write to data to the EEPROM and burn in the Configuration Bits.
• microcontrolleruser Posts: 1,194

  2018-06-04 02:57

  
  Thanks Genetix
  
  Yes.Different.That's for sure.
  
  The SX Key also runs at 20mhz while it programs.That's kind of odd.
  
  Then when it is debugging it does the same.
  
  Guess it was a tradeoff to get the debugger built into the programmer at the time.