• Please review our updated Terms and Rules here

Book 8088 discovery and modification thread

Krangerich said:
This is also new for me. So here is what I did / found out. Until now, I ordered the "Quad-Flop" controller from Texelec and a (modified?) Gotek drive.
The Texelec seemed to be the most versatile option (and probably the only currently available option apart from tons of old random FDCs on ebay).
Click to expand...
Well.. I wouldn't say the only available one if you're handy (I have spare blank pcbs left.. or if motivated enough, i would build another one) of my quad floppy controller (forked from Sergey's original board). but hope the TexElec works for you, At the time I needed them, none existed outside of hard to find old ones on ebay.
 
Krangerich said:
This is also new for me. So here is what I did / found out. Until now, I ordered the "Quad-Flop" controller from Texelec and a (modified?) Gotek drive.
The Texelec seemed to be the most versatile option (and probably the only currently available option apart from tons of old random FDCs on ebay).
For the Gotek drive, the best option is one with an AT32F435 chip on it (there are also STM<something> - old and AT32F415 - less memory). There are versions of a Gotek drive on the internet, that are already modified for convinience:
- already flashed with FlashFloppy (way better firmware)
- modified with a OLED display (instead of three LED digits)
- modified with a rotary knob
- modified with a speaker or buzzer for floppy sounds

In order to connect a floppy to the controller, you originally had to use a 34 pin floppy cable. There was a direct connection to the one drive (drive B / fd1), then a cable twist and a connector to the other drive (drive A / fd0). With the Gotek, I assume that we just need a straight cable, since the Gotek seems to have a Jumper for choosing between fd0 / fd1 and will probably "emulate" the cable twist.

The Gotek also has a 4-pin 3.5" power connector, and I need figure out where to take the 5V from, when everything arrived.

From the software side, the PC8477B controller on the Texelec is pretty common and compatible to the original NEC µPD765 controller (using port 3F0-3F7). Thats the single important thing when you need low-level compatibility in order to run old Minix, PC/IX, Xenix or whatever.
For the BIOS, the XT-IDE bios seems to support it - and the Texelec also has an optional BIOS. But BIOS is just software and thanks to Sergey, all the BIOSes are open source. If something doesn't work as expected, I feel confident enough to make it work.
Click to expand...

The QuadFlop is way overkill for this, pretty much any generic multi io card would work since the floppy side should work in 8 bit mode. You might just need to disable the parallel and especially the serial ports on the card to avoid conflicting with the ones on the Book8088 (relevant if you want to use a serial mouse).

To power it just find 5V on the card, in a multi IO controller you can find it in a game port connector and you would just need a single dupont female to female wire since ground is already connected.
From the QuadFlop itself I don't know, you'd have to use a multimeter to find a suitable point
 
sorphin said:
Well.. I wouldn't say the only available one if you're handy (I have spare blank pcbs left.. or if motivated enough, i would build another one) of my quad floppy controller (forked from Sergey's original board). but hope the TexElec works for you, At the time I needed them, none existed outside of hard to find old ones on ebay.
Click to expand...
Of course, but for the beginning I wanted to see how / if the overall setup works and train my tinkering / soldering skills with a self-built card later :)

Yrouel said:
The QuadFlop is way overkill for this, pretty much any generic multi io card would work since the floppy side should work in 8 bit mode. You might just need to disable the parallel and especially the serial ports on the card to avoid conflicting with the ones on the Book8088 (relevant if you want to use a serial mouse).
Click to expand...
But the only downside would potentially be the price, right?

Since current ebay prices for retro things here are not substantially cheaper (and isn't a relevant factor for me), I've decided to enjoy the customization options, the BIOS and the display header
 
I have installed Intel D8087-1 co-processor, but it is being heated too much (known issue). Do you have any ideas on how to cool it? Custom made heat dissipation latch? Or will it be safe to permit it to operate at that temperature, as it becomes really hot in half an hour of operation?
 

Attachments

  • Co-processor.jpg
    Co-processor.jpg
    996.4 KB · Views: 5
If I was to get a new FDC controller such as the Texelec QuadFlop, would I need to use the BIOS on the card or would it interfere with any kind of floppy support in the main (nOp v1.0.5) BIOS?
 
Vitalii said:
I have installed Intel D8087-1 co-processor, but it is being heated too much (known issue). Do you have any ideas on how to cool it? Custom made heat dissipation latch? Or will it be safe to permit it to operate at that temperature, as it becomes really hot in half an hour of operation?
Click to expand...
How much is "too hot"? I haven't put a 8087 to my Book8088, but in my IBM 5150 and 5155, which both have an 8087, it's too hot to touch for a long time, but not so hot that you can't touch it even for a short time. I don't think the Book8088 would be any different from that, even at 8MHz.
 
It is about 50 to 55 degrees centigrade, I presume the temperature is about the same as in your IBM computer. But I have operated it with an open latch, and if I close it it will run in the confined space and the temperature will definitely be higher.
 
Vitalii said:
It is about 50 to 55 degrees centigrade, I presume the temperature is about the same as in your IBM computer. But I have operated it with an open latch, and if I close it it will run in the confined space and the temperature will definitely be higher.
Click to expand...
Sounds like it's about the same. I wouldn't worry too much but, just to be on the safe side, I would have it working like 30 minutes with the cover in place, then remove the cover and quickly measure the temp.
 
Betamax80 said:
If I was to get a new FDC controller such as the Texelec QuadFlop, would I need to use the BIOS on the card or would it interfere with any kind of floppy support in the main (nOp v1.0.5) BIOS?
Click to expand...

It looks like QuadFlop has it's own BIOS (Sergey's? :)) so it will install it's own int 13h handler for floppy over any existing, but you might need to play with it's dip switches to find working memory location for QuadFlop BIOS.
 
Vitalii said:
I have installed Intel D8087-1 co-processor, but it is being heated too much (known issue). Do you have any ideas on how to cool it? Custom made heat dissipation latch? Or will it be safe to permit it to operate at that temperature, as it becomes really hot in half an hour of operation?
Click to expand...
I wonder if 80187 can fit in this?
 
Is there anyone making the more conventional "xt-fdc" card at all?
Or is anyone aware of other new cards being made - for FDC?
Also am I missing something - are these USB > FDD boards just to allow a FDD to become "external" or do they actually allow disk emulators to work right thought?
Admittedly this is all going to be a clunky solution for the Book8088 - probably a Gotek > QuadFlop > ISA board > ISA breakout cable > laptop. Eek.
 
I believe there was a very very rare NEC chip that complemented the V20?
The 8087 get super warm - even the maker of the book8088 has said to me he knows its not well implemented.
The laptop can't even supply power reliably to the XT-IDE components with it in, slight issue and the serious heat issues too.
 
Betamax80 said:
Is there anyone making the more conventional "xt-fdc" card at all?
Or is anyone aware of other new cards being made - for FDC?
Click to expand...

Well, I make the Monster FDC. Probably an overkill for what you need it for... If you can solder, you can get the PCB only, and solder a single FDC. If you can't solder... maybe I can do that for you. If you're interested, I can check what would be the price for the components/work.
 
Last edited:
Vitalii said:
I have installed Intel D8087-1 co-processor, but it is being heated too much (known issue). Do you have any ideas on how to cool it? Custom made heat dissipation latch? Or will it be safe to permit it to operate at that temperature, as it becomes really hot in half an hour of operation?
Click to expand...
8087 co-processor will get hot. But probably not as hot to melt the case ;)
There is not that much clearance in the case to install any kind of heatsink... the best I can think of is replacing the plastic door that accesses the CPU/FPU/BIOS with a piece of aluminum, so it will conduct the heat outside. Also that aluminum plate being larger than the FPU itself, will probably spread the heat more evenly.
 
Betamax80 said:
I believe there was a very very rare NEC chip that complemented the V20?
The 8087 get super warm - even the maker of the book8088 has said to me he knows its not well implemented.
The laptop can't even supply power reliably to the XT-IDE components with it in, slight issue and the serious heat issues too.
Click to expand...
yes, thats upd72091
 
You must log in or register to reply here.
Back
Top