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Bulletin board and Modem question

I was going to try to call you but couldn't find the IP address at a fast glance; did you remove it?

I haven't tried one, but there are free IP redirector services so that you can have a 'fixed' Internet address even though your IP issues you different dynamic ones.

Anyway, if you're still around, send it again (by PM if you like)

I could even fire up a Cromemco at this end and let you log in and we could message and email on there ;-)
 
Yes sorry I took the IP address down when it didn't work. After some more research I'm starting to think the next thing to try is portforwarding on the router.

I also found some links to programs that periodically ask the ISP for the latest IP address so you can automatically update it. Though that would be a pain for everyone at the other end to have a phone book that kept changing all the time. So a static IP might end up being the answer. I gather the world is running out of addresses, and that is why they are dynamic?

Re "you would type ATDT but instead of a phone number you would use the server name or IP address (see section 5.5 of the BBS Server manual)."

Yes, that would make sense. It looks like all the bits exist to do this - just a matter of pulling it all together. Would it be possible to provide a link please to the BBS server manual?
 
Dr_Acula said:
Yes sorry I took the IP address down when it didn't work. After some more research I'm starting to think the next thing to try is portforwarding on the router.

Re "you would type ATDT but instead of a phone number you would use the server name or IP address (see section 5.5 of the BBS Server manual)."

Yes, that would make sense. It looks like all the bits exist to do this - just a matter of pulling it all together. Would it be possible to provide a link please to the BBS server manual?
Click to expand...
Probably the same place you got the software:
http://www.jammingsignal.com/files/BBS Server 1.2 Manual.pdf
 
Thanks for that - reading it now.

Re the IP address - I haven't been able to find much about this on the internet, so here is my theory anyway. I have a single router and I happen to have 8 computers on that router on a LAN. If I get on one computer and I browse the internet, then a message goes out from that computer to the router and hence to the internet, and then the 'internet' sends back some data to the same place that the signal came from.

BUT - say a computer is sitting waiting for someone to log in. It has opened port 23 and is waiting for some data. It isn't sending anything out to the internet - just waiting. Someone logs in by typing my IP address. That address gets them to my router. But where does the signal go next? Which computer does the router then feed those bytes to? Does it send them to all 8 computers? Does it send them to any of the computers? Or does it (and this is my theory) send it to a specific computer that the router knows is listening to port 23.

So - that means I need to tell the router somehow where to send incoming packets. I have logged into my router, and indeed I think there is a way. I can open up specific ports on specific computers. The router wants to know the local IP address and I have set these as static in the control panel network settings. This particular machine has a LAN IP address of 192.168.2.17 And the router allows me to open a specific port on that specific machine. So I've told it to open port 23.

Now - what I'm hoping is that any packets that come in will arrive at the router and the router will then look up who can talk to port 23 and will forward them to that machine.

The only catch - I can't test it from within my own LAN because it always works!

So, here goes the big test - my ISP IP address I'm told is 121.45.128.99

Fingers crossed (in a big way) - if someone can log in and find the board - or even the single line sign on message, then this will be working and I'll write all this up. If not - I have a colleague who is an expert on routers and port forwarding and can help me.

I have a feeling that simpler setups may not need any of the above security. A dial up connection would not. A older DSL modem that only went to one machine wouldn't either. Even Telnet was quite secure till the mid 1990s. I think it was only more recently that routers defaulted to having all the ports blocked unless you specifically unblocked them. At least sites like this http://portforward.com/ do make it easier.

If we can get this working, then yes, MikeS, it would be great to talk directly to the Cromenco. Maybe even grow it into a BBS if there is enough interest...
 
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I logged in successfully and could "dir' and see your cp/m directory. It was very quick too. Only thing is, I got an echo so when I typed it looked like "ddiirr". It worked though.

I wasn't sure how to leave a sign on message?

Tez
 
@Tez: sounds like you had local echo (AKA half-duplex) turned on.

I tried it but only connected to the server:

Dr_AculaN8VEM_Australia
connecting...

Time was 18:41 GMT (abt 1 1/2 hrs after Tez?); maybe the CP/M system was disconnected?
 
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Wow - this actually works! Much rejoicing.

It is morning here and Henk has just posted overnight on the N8VEM forum an almost identical description about opening ports. So I think this is on the right track. The board is actually out in my shed and I just tried logging in myself and it says it is busy. So I assume that someone else is using it - and that is great because it means if more than one person tries to log in you get a meaningful message back saying to try again later. And this is with no BBS software running as yet - that will be the next step.

Re double echo - I'd be interested to hear experiences from others on that one. I got a double echo using teraterm talking to the Netherlands. But the weird thing is that it only happened on the first login and fixed itself on the second login. I presume it is a matter of turning off local echo so that the only byte that comes back is the one that came from the remote machine?

There are some timeout settings that might need adjusting - eg I think it drops out after 15 mins of no activity. Not sure about the settings like whether to drop out if the BBS drops DCD. These are modem settings I think and won't apply for this application.

Baud rate is 9600. We could try up to 38400.

What BBS software would people suggest?

Addit: It looks like it hung about 6 hours ago, and then about 5 people had tried to log in after that. The default on the disconnections was no disconnection, so I've changed that so it disconnects after 5 mins of inactivity and after 30 mins of anyone being connected. Working again now and baud rate is 38400 and it is at an A> prompt. Try running wordstar (WS).
 
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Worked for me this time, although using Hyperterm I was dropping characters; probably my end, will try a different TelNet client. Said HELLO but figured WS might be messy; what kind of terminal is it installed for?

So, can I log on to one CP/M board out in the shed and then talk to you on another in the house via wireless link yet? And if not, why not?
;-)

I'll thank Leif on your behalf next time I see him in a couple of weeks...
 
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Tried it, but I had to type very slowly, otherwise characters were dropped or garbled. Even though I had local echo turned off, I still got double characters.

Reasonably, 4800 is about the fastest you're going to do with a 4 MHz Z80. Limiting the speed to 1200 would historically be more accurate.
 
Chuck's experience sounds like mine, although I didn't get any double characters. But if Tez really had no problems other than the echo, then either he was doing something different or his neighbour across the Tasman Sea changed something. What kind of handshaking have we got going there, and is it a full cable?
 
Woot!

Cool if you could thank Leif personally. I'd really appreciate that.

Am brainstorming with Henk about bbs software. Some nice packages here http://www.bbsdocumentary.com/software/AACPM/CPM/RBBS/ which ran with no errors and they are .com files. Pretty amazing considering they would have been compiled for a completely different machine. The .asc I think is a .bas file and the source looks fairly similar to the one Henk has (but the two bugs on his version are not there). I ran it on another board with the setup and it asked a large number of questions and then worked just fine. It even had an option to chain a program when it finishes, so it could chain itself and prevent users ever getting into CP/M if you wanted to.

I tried doing some tests with xmodem and that hasn't worked. The message coming back is "short packets". I suspect solving this will solve the dropped character issue too.

I tried 9600 and 38400 and no difference.

I also tried logging in via a terminal program on the local PC and that works fine. So the difference between it working on the local machine and logging in from a different PC (using the same terminal software Hyperterminal private edition v5.0) is the LAN network cabling, the router and the bridge software. Of these 3, I suspect the bridge software would be the first to look at. I couldn't find the source code - maybe it isn't out there, but it could be handy to trap data going through and trap an xmodem packet and see if it indeed it is short.

Re wireless links - yes the aim is to be working on a portable CP/M computer, out in the yard or anywhere in the house, and to connect to another one wirelessly, do file transfers, and then to connect to the CP/M 'internet', which in practice would be a BBS somewhere. I'd like to get data hopping smoothly between wireless nodes too. I've got a lot working there - I have a test setup with 4 boards and they are all running some software that tests for links with a 'ping', then builds up a database of all the boards each board can talk to. Then every now and then, each board will pick a friend at random and send it the list of its friends. (using a shell to xmodem). Over time, each board ends up with a bunch of text files which has the lists of what each board can talk to. I've got that working now (it takes all night to build up a good statistical database), and I've also got upgraded software automatically propogating through the network.

Next step is to take the list of each boards friends and work out optimum paths for any message. Probably just work through every combination - I think it should be a manageable factorial number if the number of boards in the mesh is small. Then put that list in another text file, and if a message arrives with a destination x, then every board knows the most efficient path to send it.

But an important part of all this is the ability to log into the internet from within CP/M. So that might require a modification to Leif's program, ie from within CP/M you send a command out to the serial port that contains an IP address, and the bridge software tries to connect to that IP address, and then sends back a message either with the connected data or with an error saying unable to connect.
 
Re "Reasonably, 4800 is about the fastest you're going to do with a 4 MHz Z80. Limiting the speed to 1200 would historically be more accurate."

Ok, Dropped it back from 38400 to 1200. It has got that retro feeling again.

Tried xmodem from the local PC and all ok as it was for 38400, but from another PC even at 1200 I am getting errors but less errors - some short packets and some checksum errors and some packets are ok but not enough for the file to go through. I'd be interested to see if anyone has dropped characters now at 1200.
 
MikeS said:
Chuck's experience sounds like mine, although I didn't get any double characters. But if Tez really had no problems other than the echo, then either he was doing something different or his neighbour across the Tasman Sea changed something. What kind of handshaking have we got going there, and is it a full cable?
Click to expand...

I logged in using Telnet in the MS-DOS window under Windows XP.

The echo seemed to be the only problem initially. Certainly I could get a directory without any problem. I even managed to get mbasic up! However once I did, it seem to stall.

I then disconnected and tried to log on again. I couldn't. Perhaps I was the one that hung it.

Tez
 
Yes it was stuck in mbasic. That was my fault though as I hadn't set the timeout parameters. Now, even if it does hang, it should disconnect after 5 mins of inactivity. Try again now and see if the characters are better when run at a slower rate. MikeS, you might be right, maybe handshaking is the issue. This is a 3 wire null modem connection. So no RTS etc. Leif's program has this as an option and so it knows this is the hardware setup. But maybe that isn't enough? Are the dropped characters ones going into the board (ie you type DIR and it comes back with DR?), or is it characters coming out of the board? Maybe the software needs some sort of buffering/timeouts? I've been using similar techniques with a vb.net terminal program where it periodically checks for input 10x a second and if there is a character it adds them to a buffer. If no character has come in for (say) 0.3 seconds it sends the buffer on.
 
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Hmm, I would think that a 3-wire cable would definitely cause problems, since there's either no handshaking at all or it'd be XON-XOFF, but that would probably mess up file transfers.

But that still doesn't explain how/why Tez had no problems...

Time for me to dust off some old hardware and try it myself so I know (or think I know) what I'm talking about...
 
Just tried it again (and apparently crashed it by asking for c: ); This time I tried Teleterm from an XP command prompt like Tez and it did indeed work quickly but echoing commands. Is that an option on the BBS end by chance? Looks like I really *will* have to dig it out again.

And it's time to fire up a *serious* Telcom program...
 
You have to add some bullet-proofing to your BIOS. I just logged on and was greeted with:

BDOS ERR ON D: BAD SECTOR

I take it that you don't have a D: drive.

The simplest thing is to map all references (via the select routine in the BIOS) to the same drive. So the user can't get away from the legal drives. You could even do that by hooking the CBIOS vector with the BBS software so that your system would operate without restriction when you run it locally.
 
Oops - that was me, looking for some useful software; looks like he swapped disks and the only file on a: was xmodem. b: and c: did come back empty but d: finally crashed it. Needs a watchdog.
Sorry... ;-)
 
MikeS said:
Oops - that was me, looking for some useful software; looks like he swapped disks and the only file on a: was xmodem. b: and c: did come back empty but d: finally crashed it. Needs a watchdog.
Sorry... ;-)
Click to expand...

That's okay--it was me who got it stuck in MBASIC. ;)

Here's some files to stick on the BBS. ADVENTURE and STARTREK (uses BASIC-E, included)
 
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Just tried to log in with my Radio Shack M100 but unfortunately it was busy. It ended with some garbage; what baud rate are we running right now?

Never mind; guess someone else was trying. Got in with the M100 this time, but it's still trying to read a non-existent drive d:

There are a couple of options to control echo from the BBS; maybe they need looking at...
 
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