My scope didn’t save the test capture .. Next time.
But I could see the clear ones and zeros.
Dirk cleaned up a OCR version of the program, which I cleaned up some more, and found some errors.
So that should be okay now.
Yesterday I got my MAX9814 in, last night I got it working.
Used the leds from a lightpainter project to test controlling the leds.
Why is it, that it doesn’t matter how much components and ledstrips you buy, you alway need more.
Arduino Nano, using FastLeds library and FFT.
Ledstrip is WS2812, and the MAX8914 microphone
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
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.
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)
Below board replaces 2364 (8k) with a 28c256 (32k 4 roms) socket.
My design in Kicad
The rom can be selected using the pressing restore while starting the C64. ( This button press to select is not my idea but I liked it, when I find the original idea I’ll post it.
After ordering and testing, I’ll attach the Gerber files.
Followup on
UPDATE 20230702 20230703 20230714
While working on a Lidar project, my mouser components came in.
Now I have to find a IO address decoder schematic I made a while ago.
This ISA board is going to have a Wirewrapped setup. There is a 8255 IO chip, and uses 3x 74138 for IO address decoding, OR i will use a setup i’ve made for my 6502 using an atf22v10.
What to controll using this 8255? First some Leds, later a LCD display.
Below the 3 mentioned IC’s
The 8255 is a chip like the 6522 used in my DIY 6502 elsewhere on my site.
Overview of comparable IO chips. ( Not interchangeable due to bus timing!)
Most of them have 8 data lines and 2x 8 IO bi-directional lines.
| CHIP | NOTES |
| 6522 | 6502 based machines |
| 8255 | 8088/8068 based machines |
| Z84C2008 | Z80 (called PIO) |
| 8155 | 8085 / 8088 |
| 8520 | 68000 amiga |
| 6821 | 6800 |
UPDATE 20230702
Started wirewrapping, luckily i’ve got a big choice of colors. That makes finding the right signals a breeze.
UPDATE 20230703
Found my schematic
Above uses 3 74138 decoders, address can be “programmed” using jumpers (not used on my prototype board) . Address 0400h in above example.
A15 – 0
A14,13,12 – decodes to OUT-0
A11 – 0
A10,9,8 – decodes to OUT-4
A7 – 0
A6,5,4 – decodes to OUT-0
A3 and A2 are not used (see note)
A1 and A0 are register select on the 8255
Address 0000,0100,0000,xxrr
xx can be a 0 or 1
the 8255 can be controlled using
0400h 0401h 0402h
but also
0404h 0405h 0406h
0408h 0409h ….
040Ch ……
UPDATE 20230714 – Alternative address decode test with ATF22V10
UPDATE 20230803
UPDATE
Miswired second 74138.
Tested with below code
mov dx,503h # control register mov al,80h # output port a,b,c as standard IO/output out dx,al # 16 bit IO mapped IO out mov dx,500h # data register mov al,0 # 0/ff all on/all off out dx,al
I’ve got some micro cassettes with programs for P2000 and the Microtrainer (SDK-85).
Lets try to get this into executable code again.
(I sold my Philips P2000 last year before I found these tapes)
I bought a Cassette player (voice memo recorder) from Marktplaats (dutch ebay), and a mini jack cable (2.5mm to 3.5mm)
There are two things i’m going to try.
Converting the recorded audio into executable code using python or Puredata.
And making a print to connect the tape player to the SDK-85.
Connecting the player to a soundcard gave me:
Signed 16bit 44.1 kHz
(there are simular projects like this for C64 tapes and alike)
So there will be FFT tricks involved.
While browsing though this book:
I found this schematic: (page A1-39)
So that’s next to build
Got a delivery today …
Woot .. let the 8088/v20 hardware hacking commence!
First to do: LEDs, everybody loves blinking leds.
Next: Probably a address decoder with a VIA/CIA and a LCD Display.
Now I have to wait for my mouser order to be delivered.
Started drawing a Cassette interface in Kicad.
This so i can read back my old cassettes with programs.
(And write some new stuff)
I’m planning to buy a small micro cassette player.
With schematic below, I’m going to use it as save/load device.
But also with the same player, I’m going to convert the tape to a wave file, and try to decode the program using python.
While I’m at it, reading the old manuals, a RS-232 interface would be nice also!
UPDATE 20231016
This is the final version
Information about the 7655A.
A eprom WITH IO ports! Amazing piece of history hardware.
Testing some sims on Linux and Android
