Tag Archives: hardware

Mikrotik Wifi, 80386 and Lilygo streaming

Quiet days, I working on some art.

But here are the last ‘prutsen’

My current Wifi setup

I’ve got a Wifi outside of my network for guest and emergency. ( 2 SSIDs)

Then a main Wifi router in my livingroom, one in my workshop/studio and one in the Attic (Electronics Lab)

So three main Wifi AccessPoints. These all have the same SSID’s but on different frequencies. That way i’ve got roaming in and outside my house.
Also some virtual accesspoints are configured.
I’ve got a main, folkband, IOT, guest-inside all on 2.4Ghz and 5Ghz.

I watched a lot of YT presentations about Mikrotik Wifi.

So I ended up with DFS safe channels 20Mhz for 2.4 and 20/40Mhz Ce for 5Ghz. (subchannels for each after some frequency scanning)
(2.4 does a failback to 20Mhz whenever there is even one client detected which connects only on this band. Such as some old IOT stuff)
2.4 in only 1,6 and 11 no overlap, each on another device.
300Mbps is sufficient for my wifi 🙂

I’ve got accesslists in place and i’m going to read into kicking a client when the signal strenght is below -50dB

80386 (DX) Computer

Besides my 8088 and 8086 machines I needed a machine which could run our old demo’s. So I bought a new toy.

It has 8Mb Ram and runs at 40Mhz.

I’ve noticed that many of my VGA register manipulation code, can’t be run on a modern VGA monitor, I need to use a CRT for that .. Another thing to buy

Lilygo T-Display S3 Streaming

Not my code: https://github.com/Steve5451/esp32-stream-desktop
A very cool project!

Needed to fix arduino code, due to the TFT_eSPI library issues.
And I’ve got a S3 with another resolution, but that was an easy fix.
Then needed to reinstall nodejs with another version.
Had to modify the code because the tcp server would not start.
Weird errors logging, but in the end fixed … very cool

I probably end up designing a 3D printed case that looks like a monitor or tv.

MartyPC

Perviously i’ve posted about PCem

But I wanted to have a emulator which could load extension biosses also.
This for my own tinkering.

I was told to look at MartyPC and PCE/ibmpc

I don´t like it being written in Rust, but it does the job.

Running the Basic Extension Rom
Running one of my own roms. I knew it didn’t work, now i can use the buildin debug to see why!
Another of my test roms, which is working!

ROM config part i’ve got in martypc.toml

rom_override = [
    { path = "./roms/BIOS_5160_09MAY86_U19_62X0819_68X4370_27256_F000.BIN", address = 0xF0000, offset=0, org="Normal" },
    { path = "./roms/BIOS_5160_09MAY86_U18_59X7268_62X0890_27256_F800.BIN", address = 0xF8000, offset=0, org="Normal" },
    { path = "./roms/myromextension.bin", address = 0xF6000, offset=0, org="Normal" }
]

GLABios for Laser XT/3

In previous post :

I mentioned a 2 ROM setup because the 8086 is 16bits instead of 8.
So I was wondering that maybe a recompile was needed, or the data being split over two roms (odd/even)

The guy from GLABios was so kind to build me two interleaved roms.

So while working on a padded bench, I tested the ROMs.

Working outside .. on the padded bench

Back to the roms, it didn’t work!

But I missed a detail in the technical manual (the bold text)

In Turbo XT /2 and Turbo XT /3, there are two 28-pin sockets for ROM,
both of them are occupied by 2764 which stored the BIOS. The contents
of the two 2764 are identical.
One of them contribute the ODD Byte to the system and the other EVEN Byte. Together they support 16 Bit BIOS
access.

I don’t know why this is how it works, but when I flashed two the same 28C64’s it worked!
(I also tought that is was strange that both original roms had the same markings.

It workes!

Only remarks/observations:

  • There was a longer wait time before the CF Card was detected/accessed
  • GLABios mentions 8088 in the splashscreen, but the machine is a 8086

UPDATE

GLABios was not updated for displaying 8086 yet.
Error 1701 was the (old spinning) harddisk not being connected.

Nice .. harddisk infomation like size, rom address and CHS

8086 sideway scroller ‘n stuff

Today I was working on my own brew ISA card (wirewrapping).
Did some mini modeling stuff.
Sorted some pipetunes.
And played around with my 8086.

Got it on a desk now, and replaced the harddisk with the CF card.
Also got an old SoundBlaster working, so i wanted to see what of my old code could still run.
Apparanty most code was compiled for 386/486 🙁
So i recompiled some stuff.
Below a horizontal scroller example.

Meanwhile i got my new fans in for my NUC (Kodi player, it was making a hell of a noise due to bad ball bearings.

New Roms (eeprom)

Got some new roms in.
These are for my 8088/8086 the 6502 computer and C64 cartridges.

While I seldom had any problem writing to these, now I could not write one!
Erasing didn´t give me an error?!?

henri@zspot:~/projects/wozmon8088/mon8086$ minipro -w mon8086.rom -p AT28C64
Found TL866II+ 04.2.129 (0x281)
Warning: Firmware is newer than expected.
  Expected  04.2.128 (0x280)
  Found     04.2.129 (0x281)
Erasing... 0.02Sec OK
Writing Code...  9.57Sec  OK
Reading Code...  0.12Sec  OK
Verification failed at address 0x0001: File=0xAA, Device=0xFF

Whenever you get this, check the markings of the chip!

Mine are AT28C64b !!!!!!!!!!!

Change your command accordingly.
Another thing to watchout for is write protect, look at the commands

minipro -l | grep 28C64 
Found TL866II+ 04.2.129 (0x281)
Warning: Firmware is newer than expected.
  Expected  04.2.128 (0x280)
  Found     04.2.129 (0x281)
AM28C64A@DIP28
AM28C64A@PLCC32
AM28C64A@SOIC28
AM28C64AE@DIP28
AM28C64AE@PLCC32
AM28C64AE@SOIC28
AM28C64B@DIP28
AM28C64B@PLCC32
AM28C64B@SOIC28
AM28C64BE@DIP28
AM28C64BE@PLCC32
AM28C64BE@SOIC28
AT28C64
AT28C64@PLCC32
AT28C64@SOIC28
AT28C64B
AT28C64B@PLCC32
AT28C64B@SOIC28
AT28C64E
AT28C64E@PLCC32
AT28C64E@SOIC28
AT28C64F
AT28C64F@PLCC32
AT28C64F@SOIC28
CAT28C64A
CAT28C64A@PLCC32
CAT28C64A@SOIC28
CAT28C64B
CAT28C64B@PLCC32
CAT28C64B@SOIC28
XLE28C64A
XLE28C64A@PLCC32
XLE28C64B
XLE28C64B@PLCC32
XLE28C64B@SOIC28
XLS28C64A
XLS28C64A@PLCC32
XLS28C64B
XLS28C64B@PLCC32
XLS28C64B@SOIC28
28C64A
28C64A@PLCC32
28C64A@SOIC28
28C64AF
28C64AF@PLCC32
28C64AF@SOIC28
28C64B
28C64B@PLCC32
28C64B@SOIC28
UPD28C64
UPD28C64@SOIC28
KM28C64A
KM28C64A@PLCC32
M28C64
M28C64@PLCC32
M28C64@SOIC28
M28C64A
M28C64A@PLCC32
M28C64A@SOIC28
M28C64-xxW
M28C64-xxW@PLCC32
M28C64-xxW@SOIC28
M28C64
M28C64@PLCC32
M28C64@SOIC28
M28C64A
M28C64A@PLCC32
M28C64A@SOIC28
M28C64-xxW
M28C64-xxW@PLCC32
M28C64-xxW@SOIC28
X28C64

Laser XT/3 Bios

As posted before

I really like GlaBios for my 8088, so today I got my Laser XT/3 8086 machine from the attic.

Mmm TWO ROM’s thats interesting

Looking futher in the schematics I found this. Apparantly there is a 8K ROM configured in a D0-D7 + D8-D15 setup. (16 bits)

Found a technical manual, this is a excerpt.

In Turbo XT, there are two 28-pin sockets for ROM, one of them is
occupied by a 2764 which stored the BIOS (Basic Input Output System).
The other empty socket is used to house a 32K ROM, such as the BASIC
ROM

And about the XT/3 version which I have.

In Turbo XT /2 and Turbo XT /3, there are two 28-pin sockets for ROM,
both of them are occupied by 2764 which stored the BIOS. The contents
of the two 2764 are identical. One of them contribute the ODD Byte to the system and the other EVEN Byte. Together they support 16 Bit BIOS
access.

This could be an interesting chat with Greg ..

Meanwhile i’m going to look how to split a rom into odd/even.
Maybe i have to write a little python program for this.

Well, thats enough for today.

Lets fix my Cat S60 Flir phone, so i can track the hedgehog in our garden. (Battery replacement and powerbutton fix)

I fixed several phones before, (broken screen. touch not working). But I hate how some manufacturers build them.

XT-CF-Mini Bootable 8-bit ISA CF Card Interface – XT-IDE

Today I got this card (I bought it on Ebay)

It’s fitted with a 64Mb card. Note: the XT at my parents place had a 20Mb harddisk!

It can boot / emulate a harddisk with MsDos installed.

Replace an old or dead hard drive in a vintage PC with a hassle-free, reliable CompactFlash card!
Plug-in and go! (well, as much as you can expect with these old machines)

Brand new!
Built and tested.

Open Source!

This bootable expansion card provides a Compact Flash card interface to 8-bit ISA systems such as PC/XT. Typically paired with a 64MB or 1GB CF card. Silent, and more reliable than an old mechanical hard drive.

By default the XT-IDE BIOS comes configured for:
XT(and higher)-compatible BIOS.
Use the XT-CF-Mini’s IDE interface at 300h, no IRQ.
Boot first hard drive unless user presses A for floppy.
Any of the above can be changed with the simple DOS utility and built-in switches.

Switches and jumpers control:
I/O port for the 8-bit IDE (CF) interface
I/O port for the Option ROM
Option ROM Enable
Option ROM Write-protect

Note: Not all CF cards will work. Most work, but some don’t adhere to the CF standard fully, and won’t work. The full size XT-IDE card with an IDE>CF adapter, is compatible with more CF cards.

https://github.com/Bluelavasystems/XT-IDE-CF-MINI
XT-CF-Mini Pcb designed by Monotech Pc’s and released opensource GNU General Public License v3.0

It is from Blue Lava Systems, who took the schematics from Sergey Kiselev, who took the design from James Pearce.

The harddisk extension is XT-IDE Universal BIOS.
And can be flashed.

Schematic below

ROM address D0000, and IO port 300h does not need a IRQ

After installing this on my 8088/v20 motherboard I tested this with GlaBIOS, but it gave me one beep, and after that it woukd reset the machine.

Testing with the original Phoenix Bios and PCXtBios worked for me.

UPDATE: Bad contacts and a eeprom I didn’t trust.
Greg gave me version 0.2.5 of Glabios, which I burned to a new eeprom. And I cleaned some contacts.
(Checksum rom changed with every reset)

The Card and my extension bios both run with all bios-ses

Amstrad/Sinclair PC200 dualscreen

While doing some wood work, routing and painting. I managed to have some time to experiment with my PC200.

The Amstrad PC20 / Sinclair PC200 was a home computer created by Amstrad in late 1988. The machine was available in two versions, Sinclair PC200 and Amstrad PC20. (US/UK?)

In addition to MS-DOS 3.3 and PPC Organiser (a memory-resident suite of utilities), the PC20/PC200 was supplied with GEM. (I do not have those disks)
https://en.wikipedia.org/wiki/GEM_(desktop_environment)

The limited CGA graphical capabilities and PC speaker sound output were greatly inferior compared to other home computers of the time.
I has a modulator to connect a TV and could do hercules graphics on a sub-9 interface.

I got this computer a long time ago. (I still have to post pictures of my collection and getting them out of storage)

Info about this machine:

Build in 1988, Intel 8086 @ 8Mhz 512KB memory 3.5″ Floppy drive
TV Modulator Pal 640×200 CGA and Hercules

PC200

It still had a floppy in its drive, NIMMO Disk Juli 1992

Apparently this machine was used with a modem to do some interviewing for the University Amsterdam using Telepanel/Interview!

The ROM has several language options which you could set with dipswitches.

Debug part of ROM

Besides the machine having a “amiga” like case, it has two ISA slots behind a little trapdoor! How cool is that!

Dirty view of the ISA slots (One containing a RTC card)

Enabling only CGA on the machine and plugging in a Hercules card, you can do Multiscreen!
CGA and MDA addresses don’t conflict!
And if the ROM supports it .. dual screens baby!

Left Hercules and Right CGA

I used a debug command to fill the right screen

f b800:0 1000 ‘f a s h’

Cool little machine

Running old masm/precompiled machine code crashes. I’ll have to look into that.


Starfield in a bootloader (No OS)

Here is the starfield running from a bootblock loader (No MSDOS)

I threw my back out last week, so I could not move the old 8086 to a better place. I wanted to prepare this machine to boot from floppy disk.

The starfield above boots into VGA mode 13h (320×200 256 colors)

This one also has a Sound Blaster, so I can test music in a boot sector also!

My 8088 (v40) board has VGA also now.
I’m waiting for my ISA-PCMCIA card as replacement for a harddisk/floppy

Another logic probe

I’ve build a logic probe a while ago. (Mentioned here)

Today I got the EIStar LP-1. Its just a cheap easy probe, but does the job.
My version is only TTL and this one is TTL/CMOS (cmos is better when measuring arduino’s outputs)
TTL – Logic 1 = 4.75 -> 5V
CMOS – Logic 1 = more around the 3.3/3.7V

Only thing my version has which i’m missing is a pulse detector.
One millisecond puls gets clocked into a latch and keeps a led on.

Schematic I found (some similarities can be seen with my version)

From freeshell website