Search found 1754 matches

by riden
Fri Oct 28, 2005 8:19 am
Forum: New Product Ideas
Topic: Offering PICs with bootloaders already programmed
Replies: 2
Views: 1817

Check the pic section, the 16F88 has the option of having the bootloader burnt in. Thanks for the pointing this out. The thought did cross my mind when I posting my previous message that maybe, somewhere on the site, I could order a PIC with the bootloader on it. I will say, in my defense, that I m...
by riden
Fri Oct 28, 2005 8:08 am
Forum: SparkFun Product Questions
Topic: my projects
Replies: 7
Views: 4695

my goal is to build a 25MHz generator to beat my 12MHz wavetek but then to extend that design to use some of the monster 100MHz+ DDS engines from AD and see if I can get above the 50MHz range. I don't really have the background to deal with the RF issues involved in outputting clean signals at 100M...
by riden
Thu Oct 27, 2005 8:11 pm
Forum: New Product Ideas
Topic: Offering PICs with bootloaders already programmed
Replies: 2
Views: 1817

Offering PICs with bootloaders already programmed

It would be nice if SparkFun would offer PICs with the Screamer boot loader already programmed into it. That way, a customer can download the Screamer PC client and be able to download their programs into the PIC without having to have a PIC programmer. I know it would be a hassle to have to deal wi...
by riden
Thu Oct 27, 2005 7:57 pm
Forum: SparkFun Product Questions
Topic: digital chess/scrabble clock
Replies: 1
Views: 2011

I don't think using a PIC or other microcontroller for this project is an overkill by any means. You could built a timer using discrete components (digital counters and LED display instead of LCD) but the wiring using a PIC and LCD will be drastically simpler and use far less components. If you don'...
by riden
Thu Oct 27, 2005 7:42 pm
Forum: New Product Ideas
Topic: Graphical LCD Carrier Board back light inverter chip?
Replies: 7
Views: 3488

It does the job quite nicely. Just remember that the version having the built in inductor is a QFN package. I glued my chip upside down to the back of the LCD and carefully soldered the connections dead-bug style. Better fabricators than I would have designed a PC board and properly attached the dev...
by riden
Thu Oct 27, 2005 7:36 pm
Forum: SparkFun Product Questions
Topic: my projects
Replies: 7
Views: 4695

Function generator

I'll be watching with interest your progress on the function generator project! What is the maximum frequency that you would like to generate? I've built a couple of function generators using software only synthesis. My top range using a PIC was about 65KHz and over 200KHz using a low end AVR chip. ...
by riden
Thu Oct 27, 2005 12:59 pm
Forum: New Product Ideas
Topic: Graphical LCD Carrier Board back light inverter chip?
Replies: 7
Views: 3488

If you are looking for an inverter to drive an EL panel, I've used the Durel 355B device. The QFN package requires ZERO external componets as it has the inductor built into the tiny package.

http://www.rogerscorporation.com/durel/ ... 052A03.pdf
by riden
Thu Oct 27, 2005 12:53 pm
Forum: Boot Loading
Topic: Screamer and Proton+
Replies: 2
Views: 4678

Screamer and Proton+

I know that this topic has arisen before in various flavors, but I am unable to use Screamer to load hex files created with Proton+ because the required jump to my program is not at location 0. There was even a discussion on the Crownhill site where there was confusion because Proton+ already is "bo...
by riden
Tue Aug 30, 2005 6:48 am
Forum: SparkFun Product Questions
Topic: Water level detection
Replies: 9
Views: 6520

I can think of a few factors that could influence the approach taken. 1) Is it permissible to have a sensor come in contact with the liquid whose level you're measuring? If you're measuring water levels in a lake, for instance, it would okay to insert a sensor in the liquid. However, in a food proce...
by riden
Sat Aug 13, 2005 9:15 pm
Forum: Boot Loading
Topic: PIC16F88 Bootloader RB2 and RB5
Replies: 3
Views: 4564

After wrestling with an 16F877A LCD init problem, I decided to move the project over to a 16F88 running the bootloader to troubleshoot the LCD driver code. After porting, I had the "same" problem with LCD. However, what I came to discover is that it wasn't the same problem. I was using RB5 for a dat...
by riden
Mon Jun 06, 2005 9:49 am
Forum: Boot Loading
Topic: Screamer bug fix
Replies: 34
Views: 19342

Not familiar with Java's comm api - but I am assuming inp.read() is a blocking operation otherwise what would it return when there are no new chars available? The api can be set to block, return after at least n chars have been received, or timeout if no data is received (returning -1). Should be a...
by riden
Sat Jun 04, 2005 1:03 pm
Forum: Boot Loading
Topic: Screamer bug fix
Replies: 34
Views: 19342

Thanks for the information about the free version of the compiler! This will make things a whole lot easier on this end. Also, I agree that T1CON should be explicitly initialized, always good to have everything in a known state. One would think 13ms should be plenty of time to send the ACK but there...
by riden
Fri Jun 03, 2005 11:10 pm
Forum: Boot Loading
Topic: Screamer bug fix
Replies: 34
Views: 19342

Increasing delay before loader transfers control

As part of a PIC development tool that I'm writing, I've implemented the downloader protocol in Java. However, I've noticed that the loader often fails to load because by the time the ENQ has been recognized and the ACK sent to the PIC, the bootloader timer has timed out and transferred control to t...
by riden
Fri Jun 03, 2005 10:54 pm
Forum: Boot Loading
Topic: Screamer bug fix
Replies: 34
Views: 19342

I'm using the 1.4 (6/16/2004) version of the PIC bootloader HEX files and have a suggestion for a small improvement. The existing code reads the line data in a loop and then executes another loop to calculate the checksum. for(i = 0 ; i < record_length ; i++) //Read the program data { temp = getc();...