Great Weekend Project For The Propeller DIP Plus Kit

[idbruce]

Hello Everyone

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.

Bruce

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.

[Leon]

I can't see any decoupling capacitors.

The capacitors on the regulators are wrong - check the data sheets.

[Martin_H]

So do you use a computer to program the eeprom on the programmer and it clones it to other chips?

[idbruce]

@Martin_H

So do you use a computer to program the eeprom on the programmer and it clones it to other chips?

When using the programmer without the optional micro-SD Card Adapter, the files needed for the target are uploaded to the EEPROM of the programmer in the form of data blocks (DAT) using the "file" directive. These files are then downloaded to the target using Chip's PropellerLoader object, which can be found in the OBEX or here, where the object is introduced:

http://forums.parallax.com/showthrea...oader&p=591445

As for targeting with the micro-SD Card Adapter, I know it can be done, but I personally haven't done it yet, so I just included that as an optional add on. I will have to do some more research to find out how to actually target the EEPROMs with the adapter.

However to directly answer your question, the EEPROM of the programmer is programmed with a computer, in which case, the transfer mode and type will be determined by the input on PIN 15 of the programmer. So basically there will be an IF ELSE situation or CASE, being dependent upon the state of P15.

Bruce

[idbruce]

@Leon

I can't see any decoupling capacitors.

The capacitors on the regulators are wrong - check the data sheets.

Okay, I know there has been a lot of discussion going on about the use of decoupling capacitors, and I have been paying attention. However when I initially built the first programmer from a Propeller DIP Plus Kit, I wired it according to the schematic presented in PE Kit Lab Fundementals, which does not include the use of decoupling capacitors, and the programmer worked just fine, with the exception of an occasional glitch. So I figured, since board real estate was at a premium for this project, I would attempt the same route. Especially since the PCB and all components must fit into this small box.

http://www.radioshack.com/product/in...ductId=2062280

As for the capacitors on the regulators, the value and the voltage of the capacitors shown are the same as the capacitors sold with and utilized by the Propeller DIP Plus Kit, which is 6.3V 1000 uF electrolytic, and as close as I can determine, the parts sold with the Propeller DIP Plus Kit should have a Nichicon part number of UVR0J102MPD. Like I have said before, I am not an electrical engineer. I am just following Parallax's documentation and supplied parts for this project.

To sum it up, the design and schematic utilizes the documentation provided in PE Kit Labs, the parts provided with the Propeller DIP Plus Kit, and is based upon an existing model that has programmed my machinery. Is it a perfect design? I am certain that it isn't. Will it do the job that it is intended to do? I believe that it will, after I shoehorn in the missing components and circuitry for the missing pushbutton. To help facilitate this, I may remove the 5V regulator and one of the capacitors, because it was not used in the first programmer.

Bruce

[idbruce]

Yes, I do believe the 5V regulator and capacitor is history. The 5V output is surrounded by traces, with no reasonable place to put a 5V rail. By removing this part of the circuitry, I believe there will be enough room for the missing components, plus provide extra access to maybe a pin or more, if needed.

Bruce

[idbruce]

@Leon

I have decided to try and find a place for decoupling capacitors, but I am going to wait until everything else is figured out.

[Leon]

That would be a good idea.

[ctwardell]

How about some 1206 SMD capacitors, should be large enough to very easily solder, yes low enough profile to be OK on the bottom of the board.

C.W.

[idbruce]

Okay, here is the latest schematic with three decoupling capacitors added, as well as a new header for the missing switch. Please note that the final schematic will have some of the part names rearranged, but the design will basically be the same. It is also noteworthy to mention that this schematic has been updated to indicate the removed 5V regulator and the filter capacitor. Now for the hard part, rearranging the board to make room for the capacitors.

Bruce

[idbruce]

I just finished rearranging the board for the three new decoupling capacitors and this is what the new component layout looks like. I must say that it is a very tight fit in some locations.

Bruce

EDIT: If you want to talk about a tight squeeze, the optional micro-SD Card Adapter will require (2) 3/16 DIA. X 9/16 LNG. standoffs with 4-40 female threads. One standoff is approximately 0.01875" from the C1 decoupling capacitor and the opposing edge of the micro-SD Card Adapter PCB should be approximately 0.020" away from the grounding tab of the regulator. And the 9/16" long standoffs should provide a clearance of approximately of 0.052 - 0.102" between the top of the silicon of the regulator and the bottom of the micro-SD Card Adapter PCB, which is based upon the specifications of the regulator datasheet. It should just "BARELY fit. The Mouser part number for the correct standoff will be 761-1638-440-AL.

[Leon]

The regulator capacitors are still wrong! See the data sheet. Use a 100 nF on the input and a capacitor with the correct ESR on the output.

Use 100 nF decoupling capacitors.

[rwgast_logicdesign]

idbruce i use those same regulators, the 5v calls for a .47uf on the input and a 22uf on the output, while the 3.3 is a .1uf(100nf) on the input and a 10uf on the output.

as far as the rest of the project cool idea if u had alot of machienary like cnc's or somethimg to program. im assuming you came up with this out of need, what do you program with it? nice fit in the enclosure btw

[idbruce]

@Leon

The regulator capacitors are still wrong! See the data sheet. Use a 100 nF on the input and a capacitor with the correct ESR on the output.

Okay I believe you and agree with you completely, because the datasheet specifically states that, but why would Parallax market a kit with inappropriate capacitors? And I must say that I know these capacitors work for the DIP40 Prop and the 3.3 regulator. I am just wondering why they would do that? I can't understand their reasoning behind this. Perhaps because it is a minimal setup design?????

Use 100 nF decoupling capacitors.

So you are saying that instead of the 0.01 uF capacitors that I used for the three decoupling capacitors, I should be using 0.1 uF? I was thinking that 0.01 uF was standard. Perhaps I wasn't paying as good attention as I thought I was.

[Leon]

Always go by the data sheet!

100 nF is the usual value.

[idbruce]

@rwgast_logicdesign

as far as the rest of the project cool idea if u had alot of machienary like cnc's or somethimg to program.

You don't need CNC equipment or other machinery to find a use for this project. For example, I have several computers on various tables and the tables are always crowded with datasheets, drawings, books, etc...(always very messy). It is very hard for me to setup electronic experiments near my computers, to say the least, so a portable Propeller programmer is nice to have for this type of situation. With a portable programmer, it shouldn't matter where the target Propeller chip is located, it could be monitoring a sensor located above water at the center of a lake. If the target needs to be reprogrammed, instead of loading your precious laptop into a canoe and paddling out to the target, just grab the handy dandy Portable Prop Programmer. If it drops to the bottom of the lake, of course you will cry, but it will only be a $50 loss instead of $2000.

im assuming you came up with this out of need, what do you program with it?

Yes, I did not have a nice setup for programming my machinery, so I created this gadget to make it easier on me. And as I said before, you can program any Propeller chip that is setup for serial programming.

nice fit in the enclosure btw

Well thank you. It was a tight fit on the first one and this new one will propably be just as tight, especially with a micro-SD Card Adapter, however this one will be much neater and appear more professionally designed.

Bruce

[Pliers]

but why would Parallax market a kit with inappropriate capacitors? And I must say that I know these capacitors work for the DIP40 Prop and the 3.3 regulator. I am just wondering why they would do that? I can't understand their reasoning behind this. Perhaps because it is a minimal setup design?

More to the point of low current requirements.

Because the Parallax example circuits use very little current, they do not tax the voltage regulators.

The voltage regulator manufactures have to meet their Guaranteed operating performance, therefore they give component values and requirements that will meet their specification.

I like experimenting. The experiment I see here would be to build the circuit and try different size caps to see what I could get away with.
You know? Start with no cap and see what happens. Then add more and more capacitance until the circuit works properly.

Anyhow, I enjoying reading your post. Keep up the good work.

[Leon]

The stability of those LDO regulators has nothing to do with the current. Read the data sheet and follow the recommendations.

[idbruce]

@Leon

I would be a real *&$%&*, if I did not at least say thank you. So thank you very much for the guidance.

Bruce

[Pliers]

Sorry to be off topic here, but I thought the question was

but why would Parallax market a kit with inappropriate capacitors? And I must say that I know these capacitors work for the DIP40 Prop and the 3.3 regulator. I am just wondering why they would do that? I can't understand their reasoning behind this. Perhaps because it is a minimal setup design?????

I tried to answer it.
Perhaps I should have called it power drain instead of current draw?