Pluggable Blades
Stackable Blades
Tiny Modules


*** This website remains for non-current information ***

Most 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 to 104MHz. All cores have counters, etc and share a common hub of 32KB SRAM and 32KB ROM. The Prop (Propeller chip) has no built-in peripherals as is usually found in other micros, but rather has an extremely powerful set of counters etc that, together with code in 1 or more cogs (each processor core is called a cog). This way, extremely intelligent peripherals can be built. The Prop has 32 I/Os and all are available to each cog and all are identical, so there is really no fixed pins to be used for a peripheral. Such is the flexibility of this chip that you could have 16 UARTs, or VGA and 8 UARTs, Composite video and a PS2 Keyboard and PS2 Mouse and a microSD and sound. There are no variants (family) of this chip because it is so flexible, you just need the same chip. It is 3V3 and uses an external 32KB EEPROM to store user code or it can be downloaded from a simple serial (usually USB based) interface (often called a PropPlug).

Some of my designs can be used with other micros.

Here are some of the newer designs...

These boards are typically 1"x1" (25x25mm) and stack vertically using pin headers and pin sockets with extended pins to allow stacking. The headers I use are 4@ 1x9 t/hole (through hole) at 0.1" pitch. I can provide these cheaply. A number of boards (modules) are available.

If not all connections are required to be passed through to the next vertical board, I use an extra set of stacking headers with unused pins removed from the headers. This is a simple process to remove the desired pins with a pair of pliers. These connectors are cheap.

Multiple processor boards can also be stacked.

These boards are typically 1.76"x1.76" (45x45mm) and 1.2"x1.76" (30x45mm).  They plug horizontally using RA (right angled) pin headers and sockets. Most will fit into ~$2.00 Hammond 1551 R/S/F/G boxes (user modified) which are also available in translucent blue. Typically I use a standard 1x6 and 1x14  pin connections where the Pin #1 is +5V regulated and Pin #2 is GND, followed by a number of I/O pins. A number of boards (modules) are available.

Multiple processor boards can alse be daisy-chained. One of the boards has provision for taking the stackable boards, making a combination of stackable and pluggable boards possible.

These boards are tiny pcbs designed for a general purpose add-on. These boards (modules) can be used with almost any micro and provide a unique add-on function.

Examples include..... microSD, USB interface, RTC (Real Time Clock), Wii interface, etc.

A small 1.2"x1.9" (30x48mm) matchbox sized microcomputer (smt) board which includes a Propeller P8X32A processor overclocked at 104MHz, 64KB EEPROM, 512KB 55ns SRAM and a microSD socket. The board requires an external power supply, either 3V3 regulated of the fitting of an onboard regulator for an external 6-9V DC (e.g. powerpack). The RamBlade can run CPM2.2 configured with 8x 8MB hard disks, all by software emulation of a ~4MHz Z80. External interface is by serial connection or by a simple cable interface using 4 resistors to a Composite Monitor (monochrome B&W) and a PS2 style Keyboard (most USB keyboards support PS2 mode).

Status: Currently available

A large 2.9"x8" (74x203mm) tripple Propeller-based processor board, using t/hole components except for the USB chip (FT232RL) and TO252 voltage regulators. One Prop has interfaces for TV (composite video) or VGA and PS2 Keyboard and Mouse. A 512KB SRAM may be fitted in a latched design which takes some pins away from the interfaces. The second Prop has a serial interface plus microSD and 512KB 55ns SRAM. A second 512KB SRAM can be fitted as can a large Flash chip. The third Prop is for general I/O use. An onboard USB PropPlug interface is provided. Power is via 6-9V DC external power pack and onboard 5V and 3V3 regulators. Three uncommitted LEDs are available. The second Prop was used to develop the Z80 (ZiCog by heater) emulation and run CPM2.2.

Status: No longer available (pcbs too expensive! ) Note: If sufficient interest I could produce more bare pcbs - they would cost $28 (minimum 10 pcbs) or $45ea (minimum 3 pcbs). Leadtime 4 weeks.

My boards are designed to be cheap and simple. Most boards are produced in low volumes and so will not always be in stock. However, I can do another small run within 3-4 weeks. This means that the pcbs cost me more but I do not have to buy large quantities.

Boards are often a mix of smt and t/hole. Most t/hole parts will not normally be soldered. I am able to supply bare pcbs and bare pcbs with (most) parts as a kit. In particular, the pin headers and cable housings can be provided cheaply - this tends to be an otherwise expensive part of the cost. When time permits, I will solder smt pcbs for a small cost.

I am in the process of building a QuadCopter. As part of that project I have designed a number of boards to control this using a Propeller chip. These will be detailed shortly.

Here are some links with more details...

QuadCopter Project - Parallax Forum

Using the Wii Gyro & accelerometers - Parallax Forum

QuadCopter Project - Parallax Forum

Also on the drawing board is my version of the Micro-Mendel utilising some of the Prusa Mendel improvements, and hopefully a few more. I have also commenced building some pcbs to control this with a Propeller. Currently also complete is a small (1.67"x1.76") stepper controller motherboard which houses 4 stepper driver boards (0.6"x0.8") which I hve also designed and are compatible with the Pololu stepper driver boards.

Here are some links with more details...

Propeller based CNC-3D Printer - Parallax Forum

MakerBot Build - Parallax Forum

Cluso's Micro-Mendel - RepRap Forum