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QuantumII
May 25th, 2009, 01:11 AM
Hi

I'm wondering if I can use my null-modem cable between S-100 machines and a PC running a terminal emulator ? And, what are the settings I need to adjust my terminal emulator to ?

I'm a complete newb at this stuff, as I have never had my hands on a s-100 machine until now.

per
May 25th, 2009, 01:25 AM
Hi

I'm wondering if I can use my null-modem cable between S-100 machines and a PC running a terminal emulator ? And, what are the settings I need to adjust my terminal emulator to ?

I'm a complete newb at this stuff, as I have never had my hands on a s-100 machine until now.

Yes, that's possible.

It depends on what serial card your S-100 got. If you got a manual for it, you'll find all the settings there.

Basically, what you need to know is:

Word length (7 or 8 bits, most likely 7 in your cause).
Number of Stop bits (1 or 2)
Pairity settings (even, odd or none)
Baud rate (problably not above 300)

QuantumII
May 25th, 2009, 01:49 AM
Heheheh manual.. No, I'm pretty much on my own here. I will have to experiment. Anyway, it's possible to use the null-modem cable, right ?

The S-100 machine in question is a California Computer Systems 2200. I have no disk drives for it (yet) so I plan to take a second trip to the place where I found it and see what I can dig up.

per
May 25th, 2009, 02:24 AM
Heheheh manual.. No, I'm pretty much on my own here. I will have to experiment. Anyway, it's possible to use the null-modem cable, right ?

The S-100 machine in question is a California Computer Systems 2200. I have no disk drives for it (yet) so I plan to take a second trip to the place where I found it and see what I can dig up.

If you got some info about it (product number, manufacter, model, etc), there might be a manual on the internett.

QuantumII
May 25th, 2009, 04:12 AM
If you got some info about it (product number, manufacter, model, etc), there might be a manual on the internett.

I tried to google it yesterday and today, and I did not get anything useful. It's a pretty straight forward S-100 system so I think I will have no major problems in getting it connected.

Floppy drives on the other hand... I wonder if I can use a bare 8" drive with the required cables connected to the controller card ?

per
May 25th, 2009, 04:43 AM
I tried to google it yesterday and today, and I did not get anything useful. It's a pretty straight forward S-100 system so I think I will have no major problems in getting it connected.

Floppy drives on the other hand... I wonder if I can use a bare 8" drive with the required cables connected to the controller card ?

About how to connect a modern PC to a S-100 system, this ( http://www.solivant.com/altair_bootloaders/index.php?album=altair_bootloaders&pagen=1 ) site is kind of helpfull.

Floppy drives... You have to get your hands on a manual there. I don't really know anything about non-PC drives and formats, but I think you at least have to know if the controller is designed for hard or soft sectored drives/disks.

QuantumII
May 25th, 2009, 04:48 AM
About how to connect a modern PC to a S-100 system, this ( http://www.solivant.com/altair_bootloaders/index.php?album=altair_bootloaders&pagen=1 ) site is kind of helpfull.

Floppy drives... You have to get your hands on a manual there. I don't really know anything about non-PC drives and formats, but I think you at least have to know if the controller is designed for hard or soft sectored drives/disks.

Thanks. I can also use the XT for this you know, so it does not have to be a modern computer.

I'll yank out the controller and see if google knows anything about it.

QuantumII
May 26th, 2009, 03:18 AM
Thanks. I can also use the XT for this you know, so it does not have to be a modern computer.

I'll yank out the controller and see if google knows anything about it.

I took out all the S-100 cards yesterday to clean them. I also took out the backplane to remove 2 exploded caps, and to fix a burnt trace on the -16V rail.

The cards inside are all original California Computer Systems cards, and they are:

- A floppy controller for both 8" and 5,25" floppy drives
- A 64 K RamCard
- A Z80 CPU card with on-board serial
- A Serial & Paralell interface card
- A S-100 terminator board

I have got a new box with C/PM and WordStar and some other programs on 5,25" floppies, but they are for another machine. Will they still work on this one (If I get a floppy connected ) or will there be issues due to CPM bios being tied up to specific hardware ?

I will get pictures posted soon..

per
May 26th, 2009, 03:32 AM
I took out all the S-100 cards yesterday to clean them. I also took out the backplane to remove 2 exploded caps, and to fix a burnt trace on the -16V rail.

The cards inside are all original California Computer Systems cards, and they are:

- A floppy controller for both 8" and 5,25" floppy drives
- A 64 K RamCard
- A Z80 CPU card with on-board serial
- A Serial & Paralell interface card
- A S-100 terminator board

I have got a new box with C/PM and WordStar and some other programs on 5,25" floppies, but they are for another machine. Will they still work on this one (If I get a floppy connected ) or will there be issues due to CPM bios being tied up to specific hardware ?

I will get pictures posted soon..

I don't think the BIOS will be an issue. Many S-100 systems are compatible, as long as the cards are compatible. Just note that some programs (like Microsoft BASIC) are sensitive for the CPU type (If it is a Z80 or an Intel 8080), but CP/M is not one of those programs.

QuantumII
May 26th, 2009, 03:49 AM
Wow, kudos to me and google: Look what I found

Manuals for the S-100 cards I have (http://www.hartetechnologies.com/manuals/CCS/)

per
May 26th, 2009, 03:58 AM
Wow, kudos to me and google: Look what I found

Manuals for the S-100 cards I have (http://www.hartetechnologies.com/manuals/CCS/)

And the floppy one states that the ROM on the FDC contains a bootloader designed to load exactly CP/M. In other words, The only thing you need to get it running is a floppy drive and a nullmodem cable.

The floppy drive from your XT will even work with it (if it's a TM 100)!


Here is a datasheet for the UARTs on the async card:
http://www.vegeneering.com/environment_control_system/z8470-dart.pdf

QuantumII
May 26th, 2009, 04:43 AM
And the floppy one states that the ROM on the FDC contains a bootloader designed to load exactly CP/M. In other words, The only thing you need to get it running is a floppy drive and a nullmodem cable.

The floppy drive from your XT will even work with it (if it's a TM 100)!


Here is a datasheet for the UARTs on the async card:
http://www.vegeneering.com/environment_control_system/z8470-dart.pdf

My XT has 2 HH 5,25" drives, but the Compaq portables has Tandon drives (I think)

I also kept the 8" drive from the tandberg box, but I believe 5,25" is the way to go :-)

The serial connector on the back of the S-100 box is a female 25 pin.. Guess I have to hack myself an adaptor to be able to plug the nullmodem cable into it.

MikeS
May 26th, 2009, 10:52 AM
And the floppy one states that the ROM on the FDC contains a bootloader designed to load exactly CP/M. In other words, The only thing you need to get it running is a floppy drive and a nullmodem cable.

Ah, if only it were that simple...

The null modem cable may in fact be the one thing you *won't* need; most systems expect a terminal on a straight-through cable and a PC/XT is configured as a terminal. Once it's up check the voltages on pins 2 & 3 with reference to ground (pin 7 in a DB25, pin 5 in a DE9); the -12V or so is transmit and the one around 0v is receive. Connect the grounds, transmit to receive (and vice versa) and those 3 wires are usually sufficient. Note that on a PC pins 2 and 3 are the opposite of each other on the DB-25 and the DE-9, but if you go by the voltage that shouldn't matter.

The CP/M BIOS is indeed custom-tailored to a particular hardware configuration, so a version of CP/M from another system is almost certainly going to have issues with different disk formats, different console (serial port) address and configuration, possibly different memory size, ROM locations/functions etc.

But maybe you'll be lucky; in any case I'm sure you'll have lots of fun!

QuantumII
May 26th, 2009, 10:58 AM
Ah, if only it were that simple...

The null modem cable may in fact be the one thing you *won't* need; most systems expect a terminal on a straight-through cable and a PC/XT is configured as a terminal. Once it's up check the voltages on pins 2 & 3 with reference to ground (pin 7 in a DB25, pin 5 in a DE9); the -12V or so is transmit and the one around 0v is receive. Connect the grounds, transmit to receive (and vice versa) and those 3 wires are usually sufficient.

The CP/M BIOS is indeed custom-tailored to a particular hardware configuration, so a version of CP/M from another system is almost certainly going to have issues with different disk formats, different console (serial port) address and configuration, possibly different memory size, ROM locations/functions etc.

But maybe you'll be lucky; in any case I'm sure you'll have lots of fun!

So, no null-modem cable required ? In that case I would need a female 9-pihn to 25-pin male or a home made one. I will check the "stock" to see what I have.

Once it's up, that is, the S-100 machine ?

MikeS
May 26th, 2009, 11:12 AM
So, no null-modem cable required ? In that case I would need a female 9-pihn to 25-pin male or a home made one. I will check the "stock" to see what I have.

Once it's up, that is, the S-100 machine ?
Well, yes, once the card with the serial port has power. I take it there are a few caps etc. that need attention first...

An external modem cable should work.

QuantumII
May 26th, 2009, 12:04 PM
Well, yes, once the card with the serial port has power. I take it there are a few caps etc. that need attention first...

An external modem cable should work.

There's no more exploding caps. 3 caps on the backplane has blown, and they were all on the -16V rail. They are placed next to every second slot. They are there to filter the power to the cards, right ? Why don't all the slots have one then ?

I believe the card with the serial port & CPU has power, the power regulator and the Z-80 get's warm.

I will look for such a cable, but I don't think I have one.. Maybe I could rig something :-)

QuantumII
May 26th, 2009, 01:18 PM
Ok, I tried it now with a known good cable (I used it to terminal into the TeleVideo machine.. it gave me a memory error :-( )

But anyway, the S-100 system.. No response trough serial, no lights on the CPU card.. I think I will have to clean it better, a lot of the jumpers have corrosion on them. I will also reseat every chip on the card.

The CPU card alone should be enough to get to the machine monitor right ?

I used one of the Compaq Portables as a terminal running Procomm 2.4.2

MikeS
May 26th, 2009, 01:29 PM
There's no more exploding caps. 3 caps on the backplane has blown, and they were all on the -16V rail. They are placed next to every second slot. They are there to filter the power to the cards, right ? Why don't all the slots have one then ?

I believe the card with the serial port & CPU has power, the power regulator and the Z-80 get's warm.

I will look for such a cable, but I don't think I have one.. Maybe I could rig something :-)

Pin 2 to 3, 3 to 2, and DE9 pin5 to DB25 pin 7 oughta do it. Try 9600,N,8,1 to start; if you get garbage you're probably close and just need to try different parameters, maybe 9600,E,7,1. If you don't get anything you're either too far off with the baud rate or it ain't working, or (unlikely) a three-wire cable isn't enough. Hit RETURN a few times quickly in case it's waiting for some data to determine the baud rate. Maybe also try 300bd JIC.

There is a ROM or EPROM with a monitor program on there (or on the memory and maybe the FDC board)? If not then you ain't gonna do anything until a bootable disk loads.

Have FUN!!!

Don't know why you've only got caps on the -16V line; maybe because it's a relatively low current supply, usually only for the RS-232 and old 3-voltage RAM chips, and maybe it's not as well filtered elsewhere as the high-current +8 and +16V lines, but I'm just guessin'...

QuantumII
May 26th, 2009, 08:32 PM
Don't know why you've only got caps on the -16V line; maybe because it's a relatively low current supply, usually only for the RS-232 and old 3-voltage RAM chips, and maybe it's not as well filtered elsewhere as the high-current +8 and +16V lines, but I'm just guessin'...

It's got caps on the two others as well but only caps on the -16 blew.

EDIT: I've just done a bit of reading in the CPU card's manual (http://www.hartetechnologies.com/manuals/CCS/CCS_2810_CPU_Manual.pdf),and it seems that there has do be done some configuration to make it boot the onboard monitor. I will clean the card carefully today, and then configure it according to the manual.

Once I get the monitor running I can begin to look at getting the floppy controller and the memory card working.

Do you think the CPU card will run on its own or will I need to have the memory card in place as well ?

Oh, and the CPU card can connect to both Altair and Imsai front panel with switches :-) Maybe a future project when (if) I get it working

QuantumII
May 27th, 2009, 02:02 PM
Ok, here's an update:

I cleaned the CCS CPU Card and replaced all the corroded jumpers. I reseated _every_ chip on the card and followed the manual in how to enable the built-in monitor.

No response over serial whatsoever. No garbage, no nothing. The LED's on the card does not light up, and if I put in the memory card, the LED on the memory card does not light up either..

If I put in the Cromemco DPU card things start to act a little different. The Memory card lights up, the floppy controller flashes it's "sel" LED and the two others are on solid. On the DPU card the "Z80" LED lights up.

Nothing on the serial port.

Based on the above, I am almost certain that the CCS CPU card is wasted one way or another. The only thing that gets hot is the Z80 CPU and the voltage regulator.

The Cromemco DPU card is probably working, but does nothing useful as it does not have a serial port. I just put it inside the case to see if it did anything.

Any suggestions on what I can try to get the CCS CPU card working, and does it require to have a RAM board in the system to actually work or can it work entirely on its own ?