> Thanks Mike for trying in vain to discredit my >entry.
>If you spent as much time researching as you did >inding flaws you will see that on 18F PIC’s (or at >east the ones I’ve used), RA4 is NOT an Open Drain.

Actually Nuxie, I did’nt spent allot of time to discredit your work. The things I saw, I was quick to spot. But, overall I did notice that your design is very pleasing on the eyes. Very pleasing.

>I have tested my design in both SMD and DIP version, >and all pins function correctly as both input and >outputs.
O.k. It’s just that I seem to remember, in fact I know that RA4 has bit me before because it was open drain. Things may have changed since then. Also, with the entire port a for that matter, but, like I said, things may have changed.

>I am working on a full SMD version, however as in >the rules through hole components were preferred so >it is easier to make. Hence why I have SMD and DIP >PIC versions. Also, by vias I meant jumpers for a >single sided board as well. Eliminating them means >it is very easy to make at home through toner >transfer or other methods. It is also hard to find >small quantities (one or two) of SMD parts.

Actually, you can get SM parts at digikey. I would use 1206 or even 1210 as they are easy to handle. If you went with all SM parts, then you wouldn’t have to touch this board with a drill!!! That would be easier, imho, than the benefits of th parts.
…at first glance at digikey, 0.1uF 1206 goes for 1 cent a piece and the disc is 2.4 cents. It also appears as thought there are more readily available of the SM than the discs.

>The PIC has diode protection on all pins inbuilt, >and as it is meant for general use most people will >not need further protection. Same for the analog >port, pull ups are not needed if it will be used as >a digital I/O in most cases.
O.k. It was just my experience, that when interfacing with other boards, I’ve popped that internal diode many times, and those 18f’s get expensive.

>As for your ‘kicker’, it is not meant to be >connected to an RS232 port obviously. I have used it >for PIC to PIC, or other low voltage level >communication. There are many small circuits to >convert it to true RS232 levels using the MAX232 or >other similar chips. I did not put on a MAX232 as I >feel the USB port is sufficient, it adds extra cost, >and then you could not connect it to 5V serial >devices.

How about using two headers for the UART, one before and one after the translator. I find that I talk with RS232 levels more often than TTL UART levels.

Now, if it’s any concearn of yours, I will tell you that if you are feeling angry with me…, you did get your revenge on me, becuase as I was taking the time to write this, I actually missed an ebay item I had be watching. It went for $50, and they normally go for $200. Dang it. Darn it. Dang it.

What is with all the negative comments? Haven’t you guys heard of constructive criticism…

I am working on a full SMD version, however as in the rules through hole components were preferred so it is easier to make. Hence why I have SMD and DIP PIC versions. Also, by vias I meant jumpers for a single sided board as well. Eliminating them means it is very easy to make at home through toner transfer or other methods. It is also hard to find small quantities (one or two) of SMD parts.

The PIC has diode protection on all pins inbuilt, and as it is meant for general use most people will not need further protection. Same for the analog port, pull ups are not needed if it will be used as a digital I/O in most cases.

As for your ‘kicker’, it is not meant to be connected to an RS232 port obviously. I have used it for PIC to PIC, or other low voltage level communication. There are many small circuits to convert it to true RS232 levels using the MAX232 or other similar chips. I did not put on a MAX232 as I feel the USB port is sufficient, it adds extra cost, and then you could not connect it to 5V serial devices.

If you or anyone else would like to discredit or find flaws in my entry, please post it on my website. I feel I followed the HaD contest rules completely, and their suggestion of a PIC programmer/dev board if you read closely.

Now, if I’m right about RA4 being an open drain, and not capable of driving high, then the circuit, in fact, would NOT work. This would void the entry.

As for the layout, Microchip has a wonderful pinnout already, and from my experience, I don’t see any great effort needed to do what’s already fairly easy with this given pinnout. What about diode protection for interfacing to the outside world? Surely you won’t rely on the low current internal ones? The I/O’s on the chip won’t last long here.
Also, I can’t remember off hand, but isn’t RA4 an open drain output? The schematic has this as driving an LED high (I could be wrong here). Also, the whole Port A in general will need pull ups, or hope an external device has pull-ups in order to input any data. Being used as analog input? Again, use protection scheme.
Port B has weak pull ups that can be turned on (is the booter turning them on?) But they are week. Let’s hope nothing on the input loads them down.
Now for the kicker, lets hope to high heaven’s that someone doesn’t actually connect a real RS-232 cable to the UART connection because there is no level translation.
Again, sorry.

Congrats

I think I more expected the winning design to be a modification of an existing product with beyond-the-original-design results. Again, nice project and congrats but where’s the “I turned my Palm III into a brain scanning machine using toothpics and a 9v battery” hacks?

When you think about the rules for this contest and look at this winning entry it makes sense. This guy worked really hard to design a very logically laid-out PC board. He did a great job at what he set out to do, and followed the guidelines of the contest.

Of course, to many of the readers of Hack a Day (and most average Joes on the street), if you handed them a PIC programmer, they’d say, “What is it?” And then when you told them what it is, they’d still ask, “What do I do with it?” On the other hand, if you cram an Xbox 360 into a laptop case, you’ve got people’s attention–and I think that’s the sort of thing a lot of people were expecting to see as a winner. Because, hey, let’s face it, for most of us, when we come here every day, we’re looking for some everyday object being used in some very unorthodox way!

I’ve enjoyed reading about all of the entries.

Props to the guy who submitted it though. Looks nice, but this isn’t what I would have expected from a hackaday winning entry.

*Brian