Quite a while back, I built a handheld Propeller chip programmer from the Propeller DIP Plus Kit and this was way before I started getting serious about making my own PCBs. I initially created this tool to program my machinery, but recently I have been using it more and more for programming proto board setups, just so I don't have to drag the computer to the project or the project to the computer. Lately I have been bouncing around the idea of focusing on single sided boards, instead of double sided boards, simply because of the dreaded through holes. So I was wondering just how difficult it would be to make a nice single sided design with the Propeller DIP Plus Kit, so I decided to redesign the original programming tool which was built with jumper wires and perf board, just to see what I could come up with. Additionally, I have also decided to share the design and concept with the forum. Please keep in mind that this project is still on the drawing board and so far it has not been tested, but I believe it is a working design. Please keep in mind that even though it is untested, I do not want this board to be produced and sold commercially, however I am posting it here for individual use, and I will probably share the EAGLE files when I am done.
Anyhow, in addition to the Propeller DIP Plus Kit, you will also need several various switches, a project box, a couple LED holders, a couple of bi-color LEDs, several miscellaneous resistors, a row of SIP pins for headers, and you may also need a micro-SD Card Adapter, but this is optional. I probably won't discuss the physical design or programming too much at this point in time, instead I would much rather discuss the electrical design of the programmer, since it is very simple. If you look at the attached images, you will find several photos of the original programmer, an image of the component layout, a photomask image (bottom layer), and a schematic of the design. You may want to print out the component layout, the photomask, and the schematic, just to make it easier to follow along.
The top cover of the project box contains several components which are used for human interaction. These components are intended to be connected to various headers located on the PCB, however these components could also be hardwired direct to the PCB if connectors are not readily available. I will begin my discussion with the various headers, having a component prefix of JP.
JP1 - This header is for the 9V battery clip supplied with the Propeller DIP Plus Kit. Basically it is just the electrical connection from the battery to the PCB.
JP2 - This header is for a rocker switch which provides power from the battery to the entire board. Basically ON and OFF.
JP3 & JP4 - These headers are for two bi-color LEDs. One LED is used for nothing else except to indicate that the board has power. The other LED is used to indicate READY, BUSY, SUCCESS, and FAILURE.
JP5 - This is the connection header going to the Propeller chip that you want to program.
JP6 - This header is used to connect an external pushbutton switch for resetting the Propeller programmer.
JP7 - This header is used for connecting a prop plug to program the internal EEPROM.
JP8 - This header can be used for connecting an optional micro-SD adapter.
JP9 - If an optional micro-SD adapter is utilized, the header will connect to an external slide switch which sets the programming mode. In one position the target chip is programmed from EEPROM and from the other position, it is programmed from the micro-SD. However, if the optional micro-SD adapter is not utilized, then a jumper is placed across these pins to indicate the target should be programmed from EEPROM.
************ LOL.... I just noticed that I missed probably the most important item, the pushbutton and header to start programming the other chip. Oh well, it is late and I am tired. I will probably post more tomorrow when I fix this problem. Until then, glance it over. Should be a nice easy project to gain a new tool for your Parallax projects.
EDIT: The new programmer will not include the ribbon cable or the DB9 connector.
EDIT: Please refer to Post #21 for the most recent update.
EDIT: Please refer to Post #23 for the most recent update.