Cluso’s Electronic Designs and Projects
15-Mar-2017: I am updating/re-designing my website. Currently some things are broken. I am working on fixing this, so please bear with me.
Most of my designs (both hardware and software) are based on the P8X32A Propeller microprocessor chip by Parallax Inc. This micro has 8x 32-bit RISC processor cores, each running at 80MHz although I usually overclock up to 96MHz or 104MHz. All cores (called cogs) have their own dedicated 2KB RAM (512 x 32-bits) register/memory/program space, counters, etc. They also share a common memory space (called hub memory) of 32KB SRAM and 32KB ROM.
The Propeller chip (affectionately called the “Prop” by many) has no built-in peripherals as is usually found in other micros. Rather, it has an extremely powerful set of counters, etc, that, together with code in one or more cores (each processor core is called a cog), effectively “bit-bang” the I/O pins to emulate all different types of peripherals. This way, a variety of extremely intelligent peripherals can be built, with the flexibility of you deciding which peripherals you require. Many peripherals/drivers are available as Objects and published for general “free” use.
The Propeller has 32 I/Os. All I/Os are available to each core and all are identical, so I/O pins are not fixed as is normal on other micros. This chip is so flexible that you could have 16 UARTs, or VGA and 8 UARTs plus Composite video and a PS2 Keyboard and PS2 Mouse and a microSD and sound. This means that you don’t require a family of chips.
The Propeller is 3V3. It uses an external 32KB EEPROM (or larger) to store user code, or it can be downloaded from a PC using a simple serial (usually USB based) interface (often called a PropPlug). A cheap USB-Serial CP2102 6pin can also be used, but it requires a simple transistor reset circuit connected to DTR – Many of my Propeller boards have this transistor reset circuit built-in.