I-Appliance BBS
The Official Source for Internet Appliance Upgrades and Mods
Amazon Honor System Click Here to Pay Learn More
BBS Main List | Sign In | Sign Up | Search | Help | Linux-Hacker.netReply to Thread | Printer |

Home / Other I-Appliances / WebPal
Can't get gdb working after building serial interface

New MessageCan't get gdb working after building serial interface (modified 0 times) zitsky
Profile
Hi. My Webpal has been in my basement for more than a year collecting dust. I just recently took it out and started playing with it. I've read this board and all the websites over and over again. I'm a system admin, but this is my first real hardware hack project. I've built a serial interface based on Bill Danielson's using a prototype board. I was pretty excited when I managed to get the serial interface working, since I'm not much good with a soldering iron. I did not cut trace JP1 yet. I was saving that until I can verify that everything works. I figured that as long as I wasn't using the infrared keyboard, that it wasn't a problem?

I can get the "Easy Rider" prompt over the serial port by doing the Reset/SW2 combination. I've managed to build gdb 5.2.1 using CentOS 3.1 as a platform. It seems to build OK and appears to have rdp support built in. However, I can never get gdb to connect to the Webpal. I can set the device and speed in gdb using 'set remotedevice' and 'set remotebaud', but gdb never seems to synchronize. After I put in the command 'target rdp /dev/ttyS0', gdb just seems to hang and never synchronizes. Should I expect to see some message from gdb? If I try to set the speed using stty, it never comes back either. I've tried building gdb with cygwin on a Windows platform but I can't get it to build properly.

One another question. I see at least two different ways of flashing the WebPal from the serial port. One way is Bill's method of using gdb and wpflash. The other is rscott's method of loading emLilo. Are these two completely different methods, or are they complementary? Is Bill's way just another way of getting emLilo on the WebPal?

Sorry if these are stupid questions. This is just my first attempt at hardware hacking. Thanks very much for your help.

11-15-2004 01:15:11

New MessageRE:Can't get gdb working after building serial interface (modified 0 times) bigbrd
Profile
emlilo and my (bigbrd) bootstrap loader are two different loaders. rscott and I both wrote these about
the same time several years ago when the webpal first appeared on the surplus market. Most people are
using my bootstrap loader...I don't think rscott has worked on his since then....although I think he
might have used this bootstrap when he was playing with the Ceiva picture frame.

The bootstrap procedure for both is to use gdb to download a copy of the particular bootstrap loader
in RAM and then to use it to program a copy of itself into flash. So, for either to work, you'd
need to be able to synchronize with gdb and download something into the RAM on the webpal using
GDB.

I don't have too many ideas as to what might be wrong. You might want to check the JP1 jumper is cut.
I think that affects receiving data rather than sending it so perhaps only sending is working for
you (e.g. you see the prompt).

If you can't get things to work, I have been working on a new procedure where you download the
code using the original webpal code. In other words, you set up the webpal to point to your
ISP (hopefully you have a dialup account or got a dialup account with your broadband account)
and then download a file from the net that reprograms the webpal. If you have access to a
dialup account, have a webpal that works with its modem, and want to try that, email me and I
will try and put together something that works. Its been on the back burner for awhile since
not too many people are still bootstrapping webpals anymore. Anyway, if interested, email
me at my bigbrd id, but at pacbell.net.

Bill

11-15-2004 21:55:00

New MessageRE:Can't get gdb working after building serial interface (modified 0 times) zitsky
Profile
Hi Bill. I managed to get it working by playing around with the serial port settings. Sometimes stty would work on Linux, but usually it would just hang on my system. I managed to get it working under Windows (with Hyperterminal) by using the MODE command first to set the serial port exactly the way I wanted it. Once I got the serial port settings right I managed to load the bootstrap code. I did try setting the serial parameters in the comm program. I'm not sure why that wasn't enough.
12-07-2004 15:12:46

New MessageRE:Can't get gdb working after building serial interface (modified 0 times) flippernet
Profile
I'm having GDB problems on the serial port too. I designed my own serial converter since I didn't have the parts in the posted design so I may still have a bug in it but it seems to work. Here's the problem...

I get the webpal Easy Rider message completely intact and intelligible so that would indicate my serial port is at least working properly in that direction but GDB won't synchronize. It reports it got notice from the target it was reset, waiting for it to stabilize... then... trying again.... got bad res value of 0,0... and finally timeout. I've tried every combination I can think of, starting GDB first, webpal first, and various delays. GDB claims to be trying to send a reset and I *can* see, depending on which I start first, that the webpal resets but that puts it back into normal mode and not talking to the serial port. Why is GDB sending a reset? Other times GDB complains unable to reset the board, try pressing the reset button. Which is counter productive for the same reason.

That the webpal appears to reset when GDB sends a reset would suggest my serial converter is working right in the other direction as well but I don't have any way of seeing the actual data.

I notice that the J11 serial port does have full handshake lines beyond simply RTS/CTS but the serial schematic did not show them being used or jumpered. Is it possible some versions of the webpal expect DCD/DTR/DSR jumpered on it's end like on the PC end?

Easy Rider reports my bootrom as v3.07beta. Does that provide any clues?

03-15-2005 22:58:58

Reply to Thread | Printer |
All times are PSTPowered by UltraBoard v1.62



Copyright © 2000, Netmake Inc. All Rights Reserved.
See Terms and Conditions for more information.




i-opener opener laptop notebook computer help drivers dll free windows dos repair fix linux mac macintosh 2000 95 98 nt pc configure hardware software sound video netscape explorer network networking lan wan software cmos fat bios printer card mouse modem ide scsi cd rom controllers scanner tape hard drive cgi scripts source code mp3