Programming The Propeller IC
Parallax, well known for its successful Basic Stamp IC, has recently introduced the Propeller: a new microcontroller with a certain difference. It packs no less than eight 32-bit processors (referred to as COGs in Propeller jargon) into a single package with only 40 pins. That design takes genuine simultaneous multiprocessing possible, and the sophisticated internal structure of the device makes it relatively easy to implement video and signal-processing applications. The Propeller can be programmed in assembly language or the high-level Spin language. The processor and the programming tools were developed entirely in-house by Parallax, with the hardware being designed from scratch starting at the transistor level.
Circuit diagram:
Programming The Propeller IC Circuit Diagram
The basic idea behind that was to avoid becoming involved in all sorts of patent disputes with other manufacturers. The result is astounding, and for software developers it certainly requires a change in mental gears. As is customary with modern microprocessors, the Propeller has a simple serial programming interface. The developer’s toolkit from Parallax has a modern USB port for that purpose, but a reasonably simple alternative (illustrated here) is also possible for anyone who prefers to work with the familiar RS232 port. Don’t forget that the Propeller works with a 3.3-V supply voltage.
Copyright: Elektor Electronics
Vpp Programming Supplies Features High Repetition Rate
The LT1072 loop comes on if the Vpp lock goes low, stabilizing at about 17V. This circuit has a clean rise time because of the two pole compensation. The LT1004 reference is biased by the 74C04 when the Vpp command line is low. The A2 and A1 give a scaled output and the LT1004 clamps at 1.23V. To control loop slewing, this circuit uses 680pF that also erase the overshoots. [Circuit diagram source: Linear Technology Application Note]