Update on console printer, testing and other issues or activities

MOST 1130 DIAGNOSTIC PROGRAMS TOTALLY RELIANT ON TYPEWRITER WORKING

Most of the diagnostic programs run under the Diagnostic Monitor, a program that provides essential hosting and common services for each diagnostic. It is a powerful capability as it supports multiple concurrent diagnostic programs, providing time sharing that is otherwise unknown in the IBM 1130 system. 

The normal operating software, Disk Monitor System, runs a single program at a time and is a card and printer oriented batch processing system. The Diagnostic monitor relocates diagnostic programs allowing them to stack in core memory, its supervisor will alternate providing processing time to each running diagnostic, and its user interface (console entry switches and typewriter) is designed to be shared across the diagnostics. 

The Diagnostic Monitor logs the status of diagnostics with typed lines on the console printer (typewriter). As each stacked diagnostic is started, it is assigned a relative number that you use to direct the console entry switch (CES) setting and interrupt (IRQ button on keyboard) to a specific number. One can also direct a CES and IRQ to all running diagnostics, if it makes sense. 

My disk functional test, diagnostic 309, depends on the Diagnostic Monitor. That first starts up, prints in initial message, then loads 309 and begins its operation. That is accompanied by a message on the console printer. 

Each command given to 309, such as selecting which drive number to test, involves setting the CES and hitting IRQ. The monitor prints out the CES value passed to 309. There are three different CES entries needed to start 309 testing the drive inside the 1130, each of which must print first. 

The diagnostic prints messages with status as it runs through its various tests, as well as printing more detailed error messages when an issue if detected. For each such printed message, diagnostic 309 calls the diagnostic monitor to do the typing and will not resume executing until the monitor reports completion of the output. 

In other words, until the typewriter is working or I find a way to fool the diagnostic monitor, I am unable to run the disk function diagnostic 309. I therefore have to invest time working on the typewriter first, before I can finish the high priority work which is finalization of the Virtual 2315 Cartridge Facility. 

TYPEWRITER SYMPTOMS AND INVESTIGATION

Any XIO instruction to type a character will cause the typewriter to begin printing. It rotates and tilts the typeball to the appropriate character position and then throws the ball forward into the ribbon and paper behind that. Starting from a known good condition when power is first turned on, I will see the typeball get partway through a print cycle and come to a halt. From that point, the motor of the typewriter is stalled. 

I triggered a shift between lower case and upper case, which worked quite well. I did find a few characters, mostly those with minimum rotation and tilt, that would complete without the motor completely stopping. However, even those moved very slowly. 

I can trigger a tab, a carrier return, and a backspace using an XIO command and I see them begin. The CR causes the motor to stall, but at least the mechanism begins to work. Curiously, the space command does not cause any spacing - no sign of any action at all. The front panel Space, Tab and Return buttons do nothing. 

I have a good 48V voltage delivered to the typewriter, Most of the solenoids do appear to operate successfully since I start printing characters or doing non-print movements. The motor seems very weak and anemic, almost like it is receiving well below 115V. I do need to check the voltages for the motor, but the most likely suspect behind all of this poor behavior is solidifying IBM lubricants. That is, the oil and grease that I mostly flushed out with my clock oil remained in small quantities and is again binding the mechanisms. 

LAPTOP PHYSICAL COLLAPSE

The primary laptop I use to work with the 1130, design code, and so forth is rapidly becoming a pile of broken parts. It is a Lenovo Ideapad with a 17" screen and i7 processor. A fatal flaw that I discovered which plagues these machines is failure of the hinges. About a year ago, the right hinge became stiff and hard to rotate when opening and shutting the lid. Six months ago, the screws tore out of the plastic case since the hinge would no longer rotate at all. Thus, the right side of the screen was detached, an ugly bit of metal stuck out, and I had to carefully move the lid to use the machine at all.

Nothing I did would free up the hinge. Internet searches turned up a litany of hinge failures, endemic in Lenovo machines that used this hinge design. Apparently they were not being repaired by the maker either, thus the owners had to buy a new laptop when the hinges froze. 

About a week ago, the left hinge began to bind up as well, thus pushing apart the plastic on the body. The screen/lid now barely holds in place when I jockey it open and I am likely just weeks away from the screen cable tearing as the death knell for the system.

I have lots of software that is licensed to the ethernet MAC address, which would be a major pain to deal with if I just moved to a new laptop. Plus there is the joy of reinstalling and reconfiguring everything I have on this system.

BOUGHT ANOTHER OF THE SAME LAPTOP, WILL SWAP ETHERNET AND DISK

I found a used Ideapad 340 17IRH that Lenovo was selling and purchased it. I plan to swap the disk drive and the ethernet/wifi parts that contain the MAC address so that I can presumably keep working as if the PC hadn't fallen apart in my hands. 

SLOWING WORK IN THE SHOP

This does slow work in the shop, as I have to baby the laptop and take extra time before doing simple things like loading a new FPGA bitstream, loading code in the 1130 core memory, or connecting to the debug serial output of the Virtual 2315 Cartridge Facility. 

BOUGHT A MOTORCYCLE LIFT TO RAISE 1130 BOXES UP IN THE AIR

Some work I do on the IBM 1130 required me to lie on the floor on pads while I awkwardly worked on objects that were 6 to 14 inches above the ground, but deep inside the box. Trying to solder wires while on my back looking up is annoying, too. 

I located a motorcycle lift that has a platform which is 87 inches wide and 27 inches deep. It can lift up to 1000 pounds getting those pesky lower areas up where I can comfortably work on them from a chair. An IBM 1130 is 29" deep and 58" wide in its basic configuration and 88" wide with the expansion frame added. 

That may appear to be an inch or two too large for the lift, however it rolls on heavy casters that are offset inside those dimensions. Thus the 1130 models will fit on the lift. The basic configuration is around 750 pounds and the full machine with expansion hits 1000 pounds. 

When I showed up at Harbor Freight to pick up the box, which the online manual shows comes in pieces that are bolted together by the purchaser, I expected I can get it into the trunk of my Tesla, with the rear seats down to allow the box to slide back far enough.

I discovered that the motorcycle lift was shipped in a crate for handling with a forklift. The crate was eight and a half feet deep, with tall wood strips across the bottom to raise the crate off the ground to permit the forklift to get under it. The weight was heavily skewed to one end. 

Thus, the boxes width and height would fit in the Tesla trunk, but the wood blocks on the bottom made it impossible to slide it in easily. The depth was too long to fit with the trunk closed, even if we could have gotten it fully inside. Lastly, the wood blocks were arranged for the forklift to fit under with the crate extending side to side eight plus feet. If they had been at right angles, the forklift might have been able to drive the crate into the Tesla, but that wasn't the situation I faced.

Somehow we got the crate into the Tesla far enough to ensure that with the very heavy end inside, it wouldn't tip out. The trunk lid closed partway and I drove slowly and carefully out to my shop. Getting the crate in the car depending on the help of the forklift. With no forklift at the shop, I had to improvise to get it out all by myself.

Fortunately, the crate wood used by Harbor Freight is so thin and cheap that I could tear apart the crate with pliers, screwdrivers and my hands, no saws or heavy machinery. I took out sections of crate, removed the big wood blocks from underneath, and then pulled the various components of the lift out of the crate one by one. 

The final piece, which was still around five feet long, I was able to slide inside the crate until it was ready to tip down to the ground. I had to pull it far enough out that it didn't pivot up and strike the inside of my car, so there was quite a bit of tugging and lifting of weight involved towards the end. 

In the end though, through sheer stubbornness, I persevered. I had the parts all on the ground outside the shop and put it together out there. I then collected all the crate parts, broke them down to more manageable sized pieces, drove it over to my condo and got it all in the dumpster that sits under the garbage chute in the building. 

I rolled the lift into the shop where it waits for the next time I need to get access tbo the lower part of an 1130 box. Currently, the typewriter that I have to work on sits at the upper portion of the machine, but it won't be long before I want to get this on the lift and ready to raise and lower. 

PREPARING NICE LOOKING ENCLOSURE FOR VIRTUAL 2315 CARTRIDGE FACILITY

I drew up a design for an enclosure that will sit inside the IBM 1130, accessibly by lifting the top grey cover to the right of the typewriter. Inside it I will mount the main box, the power distribution board, the time delay relay, the power supply and angle the main box up so its face is tilted where the operator can best see it with the 1130 cover open. 

The enclosure will be constructed of black opaque acrylic. I ordered the acrylic sheets in roughly the proper sizes but have developed laser cutter files to cut the precise outlines and various holes I will need. 

FINISHING PRODUCTION VERSIONS OF MY PCBS FOR THE FACILITY

As I receive the final components from Digikey, I am building the final versions of everything with the goal of having a full final version of the Virtual 2315 Cartridge Facility working on the VCF's 1130 system, plus a second unit ready to install on the System Source Museum's 1130.