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Help with serial interface PC to Sol-20

After you send PC2FLOP.ENT to the Sol-20 at 1200 baud, I'd then set S3 for 9600 baud and TeraTerm to 9600 baud for the XMODEM file transfer of the disk image. Otherwise, the transfer takes 50 minutes for a DSDD disk image at 1200 baud.

Mike
 
I've said it many times, setting up serial ports sucks. Gets easier after you figure out the pitfalls the first time, but it always is a test of your skills. Glad to see that the problem is solved.
 
You never cross connect two driven pins.

Dwight

This was the main point I realized, initially struggling to connect up RS-232 interfaces. There is no point connecting an input to an input or an output to an output. So whatever devices you are trying to hook up, a very good start is to look at which pins are outputs(or driven pins) and which ones are inputs on the particular device's connectors and that alone solves many potential errors in the hook up.
 
Well, I had to put the cork back into the champagne. I was able to set the serial interface to 9600 baud and loaded PC2FLOP.ent and executed the start. I was able to pick the drive number, select the serial port for the file transfer and start the XMODEM file transfer for the Northstar DOS 5.1 disk image, but when it tried to write to the disk I got the error message: Write failure on track 0, sector 0. Disk creation aborted. I was using the Tandon TM-100 2A drive from my Northstar Horizon computer. I do not know for sure if this drive works. I went and tried another Tandon TM-100 2A drive I have as a spare for my IBM 5150, but got the same error. I'll have to put this Sol-20 disk drive project aside for a few days and work on some other projects that, hopefully, are more successful.
 
Well, I had to put the cork back into the champagne. I was able to set the serial interface to 9600 baud and loaded PC2FLOP.ent and executed the start. I was able to pick the drive number, select the serial port for the file transfer and start the XMODEM file transfer for the Northstar DOS 5.1 disk image, but when it tried to write to the disk I got the error message: Write failure on track 0, sector 0. Disk creation aborted. I was using the Tandon TM-100 2A drive from my Northstar Horizon computer. I do not know for sure if this drive works. I went and tried another Tandon TM-100 2A drive I have as a spare for my IBM 5150, but got the same error. I'll have to put this Sol-20 disk drive project aside for a few days and work on some other projects that, hopefully, are more successful.

I had a few of those issues initially when I set up the drives with my Sol. Most of those troubles in my case turned out to be defective floppy disks. I bought a number of different brands of NOS soft sector disks on ebay, about 30% of them would not format or gave erratic results in use. Somehow it seems that the magnetic media has degenerated on some of them. The ones that have been most reliable for me and practically never have issues are the 3M brand. Mike uses these too and I think he also finds them reliable. So it might not be an actual drive issue, since you have tried two drives and got the same error.

In my drive setup with the SOL, I had never done one before (or even owned an S-100 computer) and my experience fitting drives and a controller to an S-100 computer was zero. So to try to avoid hardware anomalies, which could have sabotaged it working, is the reason I went for NOS disk drive units (YD-580's) and made sure all the IC socket connections on the N* card were perfect and also got a "tested & working" VSG from Mike. So when I set the hardware side of the system up I could be a little more certain that when it didn't work, it would be mainly software issues to solve, and for me that is plenty of trouble just in that area, as I'm very slow on the software side of things.
 
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Well, I had to put the cork back into the champagne. I was able to set the serial interface to 9600 baud and loaded PC2FLOP.ent and executed the start. I was able to pick the drive number, select the serial port for the file transfer and start the XMODEM file transfer for the Northstar DOS 5.1 disk image, but when it tried to write to the disk I got the error message: Write failure on track 0, sector 0. Disk creation aborted. I was using the Tandon TM-100 2A drive from my Northstar Horizon computer. I do not know for sure if this drive works. I went and tried another Tandon TM-100 2A drive I have as a spare for my IBM 5150, but got the same error. I'll have to put this Sol-20 disk drive project aside for a few days and work on some other projects that, hopefully, are more successful.

Make sure you’re using 10 hard sector disks.

Mike
 
This was the main point I realized, initially struggling to connect up RS-232 interfaces. There is no point connecting an input to an input or an output to an output. So whatever devices you are trying to hook up, a very good start is to look at which pins are outputs(or driven pins) and which ones are inputs on the particular device's connectors and that alone solves many potential errors in the hook up.

Old_hitech
I still recommend that you get a rs232 light box. It saves a lot of time and frustration in setting up RS232 connects. Your original setup should have worked. The fact that you have something working now is great but with one of the light boxes in your hands, you will be sure of what you are doing and you'll know why it didn't work. Now it was just a lucky ending. The you've added new software and a USB to serial, that likely wasn't needed. Had the Sol had a blown input, you'd still be in the dark as to what end was failing.
If something fails in the future, you'll still be wondering what part of the system failed.
Dwight
 
Dwight, Thanks for your reply. I understand your point and am ready to purchase one. Since I am thinking of connecting my Sol-20 to my Northstar Horizon at some point in the future, I can see the need. I 'googled' for an RS-232 breakout box and see a few options. Do you have a recommended one?
As for my efforts to create a bootable disk, The diskette I used for my initial attempt was a 10 hard sector diskette I received when I purchased the Northstar Horizon. I believe it is a 10 hard sector diskette as I am able to see many holes in the disk media when I rotate it in the sleeve. I did not count them, but since they were used with the Northstar Horizon computer, I assumed they were the 10 hard sector diskettes that I was looking for.
When I was trying to create bootable disk, I did not try a second diskette, but I did get a few with the Horizon so I will try a few different diskettes next time. Unfortunately, I did not receive any new diskettes with the Horizon.
 
I am back at it trying to create a bootable floppy with my Sol-20. I now have tried 3 different diskettes from at least 2 different vendors and I still am receiving the error Write failure on track 0, sector X. Each time I run the program I get different sector references of 0 or 6 or 8 or 9. Not sure why that is occurring. When I get the error I usually perform an UPPER CASE/REPEAT on my Sol-20 then follow that with EX 100 to restart the application. I set the drive to 1 and the serial port to default and it prompts Start XMODEM send now.... I then on my PC laptop using the Tera Term application Select File/ Transfer/XMODEM/ Send... I select the NSDOS-51-SSDD.NSI file and Tera Term starts sending the file and at about 25.7% complete the Tandon disk drive light turns on and shortly after that I get the Write failure error. Is this the correct way to send the file to the Sol-20 from Tera Term? Is there some other XMODEM settings I need to setup prior to sending to the Sol-20 running PC2FLOP?
 
I thought about all the help/suggestions/recommendations I received from the members of this forum and what was not working -- the write to disk on the disk drive and remembered that Mike told me about the +4.2V on the +5V line being not right. With that I brought out a spare IBM PC power supply and connected my disk drive to this power supply. I measured the +5V line and it was now +5V. I checked the +12V and it was +12V. I proceeded to run the PC2FLOP application and transfer the CP/M 2.23 48K SSDD.NSI file and it worked!! I restarted my Sol-20 and was able to boot to CP/M with the EX E800 command. Finally.....time to pop the champagne again!
 
I have no particular recommendations. The simple light with no wire cross connect is usually all that is needed but the ones with the jumper wires are handy when you don't want to solder up another connector combination that you don't have one with the right wiring. I have both in my box of RS232 stuff and seem to find use for both.
Dwight
 
There are plenty of these sorts of things around in either 9 pin or 25 pin variants , they have bi-color LED's: this link also shows where to buy them, but mostly now these sorts of things are all over ebay.

https://store.chipkin.com/articles/rs232-how-can-i-know-which-rs-232-data-lines-are-active

There is a more elaborate RS-232 diagnostic tool, I have attached a photo of one I have. The ribbon cable has a 25 pin connector on it. So what it is, is a break out box with connector pins, DIP switches & LED's. On top of that it contains a good number of IC's and its powered by a plugpack and it contains a 9V rechargeable battery. Its called a BERT, bit error rate tester. I haven't as yet figured out how to use it to its full potential.
 

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There are plenty of these sorts of things around in either 9 pin or 25 pin variants , they have bi-color LED's: this link also shows where to buy them, but mostly now these sorts of things are all over ebay.

https://store.chipkin.com/articles/rs232-how-can-i-know-which-rs-232-data-lines-are-active

There is a more elaborate RS-232 diagnostic tool, I have attached a photo of one I have. The ribbon cable has a 25 pin connector on it. So what it is, is a break out box with connector pins, DIP switches & LED's. On top of that it contains a good number of IC's and its powered by a plugpack and it contains a 9V rechargeable battery. Its called a BERT, bit error rate tester. I haven't as yet figured out how to use it to its full potential.

Wow, now that's a tester! Kudos to Crock. Dundee. :) Put's my LED based tester to shame.
 
I'm still reading through this thread, so if this has been covered my apologizes.

I'm having issues with a serial connection too. I thought most of my hair was gone, but today I've lost even more! I've had some success, but never enough, consistent enough, to really know what kinda worked. I've been trying TeraTerm, but have tried a couple others as well. Right now I've got MobaTerm sort of working. I can connect, type characters on my PC and they show up on the Sol. But, the Sol monitor carot > is still there, and as soon as I hit return on the PC, the Sol should perform a CR/LF, but since it still thinks in in monitor mode, it just shows a ? and returns to the carot > prompt. And yes, I did SET I=1 before starting, or I wouldn't have seen anything.

What would be helpful is perhaps a guide showing a pin-to-pin chart from a 4-pin, USB port to the DB-25 connector. I'm sure some here made there own cables for this purpose. Did you use a standard USB port that only has 4-pins? Perhaps the reason I'm having trouble is I'm trying to use a new style 'active' (FTDI dongle) connector cable that goes from a USB port to an 8-pin RJ45 port. From there, you can assign the 8 flying lead little pigtails to the proper DB-25 pin. Picture attached. Perhaps a cable like this won't work correctly. Apparently not - for me! :)

Also, if you did make a cable, what are the minimum signal pins you have to use. With USB, you only have 3. RX, TX and Gnd.

Any insight appreciated.

USB to DB25 Cable.jpg
 
This is from another thread, some useful info:

This is a paragraph pasted from the Sol20.org site:


If you want to try and download these programs to your Sol, here's how to do it.

Grab the *.ent file you are interested from one of the tables below.
Connect a serial cable from your PC to your Sol
Set the baud rate, data bits, parity bits, and stop bits the same on the two machines. I have difficulty getting my Sol to transfer reliably if the baud rate is higher than 1200. YMMV.
Test that the link works. Use the TERM command to do so.
On the Sol, type "SET I=1". This makes it accept subsequent input from the serial port, as if you were entering it from the keyboard.
On the PC, transfer the *.ent file over the serial link as a straight ASCII file.
To run the program, type "EX xxxx", where xxxx is the load address, and off she goes!
Mike Douglas has having troubles getting ENT programs to load into his machine at 9600 baud. After puzzling over it a bit, he found that some .ENT files are saved with CR/LF line endings. He found that deleting the line feeds from the files and telling his term program (TerraTerm) to insert a 100 ms delay after each CR fixed it -- he could then reliably send data at 9600 baud. That 100ms is to give SOLOS enough time to scroll the screen after each line.




You just do it on the Sol , with Solos running in the usual way, after you have done a reset, or after the Sol is powered when it comes up with the usual cursor. The TERM command that you type on the Sol is just a good way to test the serial link and that it is working in both directions properly. As noted the SET I=1 command you type on the SOL, makes the SOL ready to receive a file to memory, typically a .ENT file that specifies the starting address and memory addresses that the file will get loaded to in the SOL's RAM. Sending a file to the SOL this way, with TeraTerm at least, the option to select is just "SEND" not the "transfer" options which include Xmodem. They are used when you want to transfer other file formats like .COM files etc.

When the .ENT file is sending, you will see the addresses and bytes appearing on the SOL's VDU, just as if somebody was typing them in at a high speed. So its easy to see that you got the whole file and it went to the correct addresses.

******
I'm sure I drew a diagram up of the cable arrangements I use and put it on a thread, but I can't seem to see it anywhere, I'll look for it.

If you are using a USB, you would need a USB serial converter which has a small chip in it. There was some episode, a while back, involving many fake chips and some manufacturer somehow deactivated their product line in some vindictive event, but I cannot recall the details.I have avoided trying to use a USB interface as it threw in more variables.
 
Since I'm new to this file xfer from PC thingy....

All the .ENT files I have found on deramp's site are not able to be downloaded. as a file. Instead they open up as a web page. Do I need to copy the contents and paste in a Notebook file and save as an .ENT file? I've tried copy n paste directly from the webpage into the TeraTerm's terminal screen, but that has been futile. Where can I get the actual .ENT file to download? I will then try 'sending' it to the Sol via TeraTerm.
 
I think I've finally found the correct wiring for the USB-to-DB25 cable I'm using. At least I've been able to communicate between the 2 devices.

However, due to some unwanted frustration as to why the .ENT data was not transferring correctly/completely, I learned some things about the Dual Personal Module I had been using years ago. Or, I re-learned some facts I had not remembered. After reviewing the DPM docs in more detail, B. Hogg (Micro Complex) rewrote parts of SOLOS. He retained some original commands, and also added some new ones.

One of the SOLOS commands he placed was for EN. The DPM offers either EH - enter HEX, or EA - enter ASCII. Perhaps for flexibility. I can't recall this difference from when I used my Sol, but something else I encountered today that I was not aware off and just discovered while trying to transfer .ENT data. Apparently, both the new commands EH and EA, only work for a single memory location per line. So, instead of being able to string together 16 memory locations per line and hit enter, with EH, every time you enter a byte, it does an auto LF, popping up the next address for entry. No wonder I'm about to loose my mind! I'm still investigating this, but after double checking, that is the way it seems to work. So, that makes all the .ENT files impossible to load. The DMP simply chokes.

Can anyone using the the DPM confirm this? I thought I may have had a CR/LF setting wrong in TeraTerm confusing how the transfer worked, but I tried it manually and that is the way you appear to load data manually from the keyboard using the DPM. Not that anyone would want to do that - then or now! I used CUTER to start back in the day, and immediately went to a MDS when they became available. But it's sure making reviving the Sol more painful. Luckily, I have the original SOLOS module and it seemingly works with all my upgrades - with the limited testing I've done.
 
Luckily, I have the original SOLOS module and it seemingly works with all my upgrades - with the limited testing I've done.

This is the type of thing I was alluding to in a previous post. At least if you are setting up an original system, the manufacturer's documentation is there and you know almost for sure what results you should be getting and if you don't get them, to start the usual fault minding methods.

Once you have a modified or non standard system, unless it is super well documented, it can be very difficult to know what part of some problem is due to a modification, be it altered firmware or even altered hardware.

If it were me, I would stick to original SOLOS for now until you have got all of the bugs worked out and after that maybe go back to the B.Hogg micro complex OS.

One of the biggest issues I have is trying to figure out when something isn't working, is whether its a hardware issue or a firmware problem if I don't have another reference machine known to be good, or super good documentation in front of me on both the hardware and firmware. Or at least a known proven copy of the firmware to try. Then there is the PBKC problem on top of that I might suffer from more than most.

If you are tackling a machine with both hardware and firmware variations together, it could be very difficult to untangle a problem, at least it would be for me.

I sometimes find that afterthought projects which modify a manufacturer's design, firmware or hardware, throw in additional problems and they never seem to be as well documented and probably not as well tested or verified either as the original product design. This remark obviously doesn't include isolated bug fixes.
 
For now I'm back to using stock SOLOS. However, my upgrades are still in place. I can't imagine them affecting anything with the serial interface. I'm getting really strange results and it may be a result of using a USB-to-Serial cable with the chip(FTDI). I tried another brand of the chip cable and the results were the same. I don't have any other serial port to use. This is really head banging at this point. The thing is, I can enter a few bytes manually, but when I do a carriage return, it seems to go offline and no other remote commands work. I have attached 3 pics of my settings in TeraTerm in hopes someone can validate they should work. I believe they do, except for a CR resulting in having to SET I=1 again on the Sol console.

I'm trying to get the little 19 byte LOADER program loaded, but every time the input line from TeraTerm is disrupted, I have to reset the Sol to get anything back. Resulting in loosing the 19 byte loader program - again!

On a related topic.... How do you go about transferring (or sending) a .ENT file? When I go to download the ENT file it's just a webpage. Shouldn't I be able to simply copy-n-paste the hex code into the terminal screen and hit okay? Is there a way to download the .ENT file as a text file and save it locally?

I guess I just need some tutelage on this and the exact details of how it done to effectively gets some workable results. :) Sorry to cross-post some of this last topic.


TT Serial Parameters.jpg TT Terminal Parameters.jpg TT Clipboard.jpg
 
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