THE MOST ESSENTIAL PROPELLER CHIP CIRCUIT
BARE BONES is one of our favorite Propeller chip machines and continuing projects. In under ten minutes, it's possible to whip up this circuit and run the virtual LED programmed in Spin, blinking it on and off, watching it on the serial terminal.
This is the latest updated schematic to construct the Bare Bones Propeller circuit with the mentioned improvements. It has the main chip protection circuit added to the schematic for crisscross wiring and decoupling capacitors, ensuring a greater longevity chip.
ADDITIONS
The main schematic addition is one resistor to activate the BOEn disable circuit so that the Propeller can operate on less voltage, at or below the 2.7 volt reset limit. This allows experimenting with solar cells, smaller batteries with less voltage and other supply circuits. It also allows a battery to function at increased discharge levels and the Propeller chip can boot at a lower voltage.
VERSION
This updated Bare Bones Schematic is currently at version 1.4 and is subject to change without notice. It replaces versions 1.0, 1.1, 1.2, and 1.3. Use the blog's search feature to find any future changes. The suggestions from this thread, and some from another thread are now incorporated into the circuit to maximize Propeller chip performance, reliability, and facilitate ease of assembly for beginners.
LOWER POWER
The circuit allows lower power operations, mainly 3-volts with two (1.5 volts each) AA batteries, and experiments at lower voltages. Bare Bones is a good reference circuit and starting point for many projects. By itself, Bare Bones is considered to be a simple machine project with provided software on the schematic and the ability to communicate with a serial terminal, providing virtual representations.
PROPELLER TOOL SOFTWARE
http://www.parallax.com/downloads/propeller-tool-software
BARE BONES CODE
With no crystal needed, the program runs in rcfast (~12 mHz) and at 1200 baud to blink a serial terminal LED on and off. Hosted at the Parallax Forum, the link for download is found below or simply cut and paste the code into BST or the Propeller Tool software.
' Terminal LED Test Program http://humanoidolabs.blogspot.com/
' Author: Humanoido (c) 07.18.2013 Terms of Use MIT License
' Runs on Bare Bones Propeller
' Blinks one serial LED
' Boot to RCFAST (~12MHz)
OBJ
PST : "Parallax Serial Terminal"
PUB main
pst.Start(1200)
pst.str (string(13,"Serial LCD Demo",13,"Blink LED On and Off",13))
repeat
pst.str (string("LED ON *",13))
waitcnt(clkfreq/2 + cnt)
pst.str (string("LED OFF o",13))
waitcnt(clkfreq/2 + cnt)
