@gkaufman is this the correct  updated version up on pcbway https://www.pcbway.com/project/shareproject/ASCII_Video_Terminal_2.html

Hi,  Is there a link to the DHansel .HEX file for the PIC chip firmware?  

https://github.com/dhansel/TerminalUSB

Hi, 

Okay, I've built up the board, but I have a couple of questions;

1. Do I use the Terminal_V1.3_UPGRADE.hex file for the PIC chip?

2. IF I'm connecting with a 5V d.c. from a.c. adapter (WallWart) do I need to also add a jumper on the Use USB Power?

I seem to see 4.92V on PIN 1 of the keyboard connector, but I am not getting a NumLock LED on the keyboard, and I don't see anything on the VGA monitor.

If you're using a PS2 keyboard the V1.3 firmware is perfect.  If you use a USB keyboard add the USB power jumper and use dhansel's firmware.

Walt - It should be a fairly standard connector, it's a standard footprint. It's been several years and I don't have a specific part number. What part isn't lining up - the actual electrical connectors, or the two mounting pins?

Hi, 

The back row of pins seems to be off by about 0.5mm or more.  The VGA connectors from DigiKey easily drop into place on a few different kits I've built, but not on the boards I got for this ASCII Terminal.   

Since I need more VGA connectors, I have a different one on order through DigiKey.  I hope they fit.  I really don't like to bend PINs to make connectors fit, but that maybe what I have to do.  

Hi,  I got a different VGA connector and it fits the ASCII Terminal board, but it does not fit the other three terminals (VersaTerm, VT-132 and DAZZLER) boards.  They all use a different VGA board connector.  

This connector works for the ASCII Terminal board; 
https://www.digikey.com/en/products/detail/adam-tech/HD15-SN-24/9832440

v.
the VersaTerm, VT-132 and DAZZLER VGA connectors;
https://www.digikey.com/en/products/detail/amphenol-cs-commercial-products/L77HDE15SD1CH4FVGA/4888525

I ordered a VGA connector from DigiKey (2092-K66X-E15S-N-VESA-N0) for this and a couple of other projects, but this is the only board that the PINs do not line up correctly.  

Is there a link to a better fitting VGA connector?  

One more thing.

I made it.

Anyone doubted it?

The Mini VT-100 emulator.

https://abload.de/img/mini_vt100emu_single_7pjxv.jpg

Thnks for the inspiration and the force MOTIVATING me to do it on my own.

Heck , waste of human power.

A lot of poeple did the same be cause the original makers DID not share their IP.

Stupid.

is it available to purchase and try out?

Hi,

I do not sell a thing.

All my creations I have published on various sites are free of charge.

I do publish according to the Creative Commons, NO COMMERCIAL

https://creativecommons.org/licenses/by-nc/4.0/

If someone is interested I will send the gerber files via PM.

No commercial use, please.

Have a good day.

Hi,

new revised, heavily reworked pcb layout.

Changed for the footprints of OBTAINABLE parts.

Thats the most OVBVIOUS reason, why makers need the SOURCES.

PERIOD.

No debate on this, hackers.

Accept, be quiet, behave or be gone making much money.

Many changes made.
No more:

- hairy thin traces

- traces between chip pins

- voltage selector for the MAX3232.

IMHO eady for direct toner printing method.

If anoyone wants files, let me know.

I do not know of RELIABLE webspce for longtime hosting.

As of writing PRE BATA.

Just the power ogf imagination.

Nothing has been materialized yet.

Update:

Have not read further comments.

As usual, when poeple wanting to make much money without contributing to the public,

I have to become more creative.

So I did.

Hav converted the layout. Have designed a single sided board layout.
Can pe brinted out, made on a pcb cnc mill easily.

https://abload.de/img/mini_vt100_ps2singles1qkxf.jpg

THE END

Peter -

I'm sorry the project didn't meet your expectations.  I am not a professional, just a hobbyist who made up this design as a way to learn KICAD while working at home because of the pandemic.  I haven't loaded or looked at the files in over a year now, and have no time to revise them further now that I'm back to the office.

I made up the PC boards for my own use, there is no profit motive.  I can't imagine etching and drilling PC boards at home when you can have a batch fabricated for less than $10.  If you were in the USA I would gladly mail you some PC Boards for free.

Why not simply branch your revision of the project to a new Hackaday page instead of your continued criticism here.  That would be a nicer way to contribute to the hobby. 

Hi, nice You have monitored the discussion.

Initially I wanted to make the pcb pro add on card used on the Altair8800 emulator.

But the man did NOT share the layout files.

Even the files for the older front panel pcb revision  are pretty much useseless (Fritzing mess).

So If YOU want someone making a pcb at home
DO provide the source files

KiCad Eagle, Diptrace, no the high level editor like Altium and alike,

no one usually owns legally at home.

Pleas just DO it.

No problem, You have the software on Github reop?

PLS, update the files Schematics, publish the source layout files.

I do not care about f*** chineese crapmakers.

They do clone everything without asking for permssion.

How to circumvent the mising files.

For inspection I have loaded the files dl from here and PCBWAY (V2.0)

into CAM tool and imported into layout editor as well.

Edited the thin traces and did a lot more.

Changed some parts  (VGA and DC)  with those I have pruchased from dustributor TME last week.

They do provide a quick delivery, shipped in one business day from abroad.

Parts used:

VGA Amphenol, DC in (different footprint)

TME order codes

- VGA ICD15S13E4GV00LF

- DC in  ADC-002-2

- Mini DIN 6 pin  TM0508A/6

- USB-A MX-67643-0910

See the picture.

No the pcb size has a size of 100x70mm.

Mounting holes spacing 90x60mm.

METRICAL rules.

https://abload.de/img/geoff_vt100_10x100__valjbf.jpg

Thanks

Hi,

please fix the files.
The schematics lacks the names/designators of some parts.

PLS

Put the KiCad files online.
Editing the imported gerbers files is pretty messy.

PLS

When You make a project, have in mind, some poeple want to make the files at home.
No problem making doublesided pcb IF the traces are not hairy thin and the clearance are at a decent level.

Oh no!
Very narrow traces of 0,25mm wigth.

Please do avoid the way You have started traces at the solder pads.
Do not feed the traces toward the next pad, go at an angel away from the pads.

The pcb has a lot place to make it REPRODUCABLE:
anyway

Thanks

Hi all.

Be aware!
Anyone made succesfully a working pcb?
See the picture.
https://abload.de/img/geoffpcbgerberwrongtr7gkkw.png
I clearly shows a trace starting at USB port ending in Nirvana, below the body of a resistor R7.
Load the gerber files BEFORE placing an order.
Wear glasses.
Inspect cerefully.

Peter -

That trace is a remnant of a prior version that I missed deleting.  The tracing is connected properly.  It looks silly, but doesn't hurt anything. 

I can provide gerber's with the tracing removed, but I haven't tested the revised version myself (and I know the existing gerber files do work fine).  If you'd like an updated version to order let me know.  Once you confirm the new version is fine I can replace the files on the web.

- Gary

I've built a (except connectors) surface mount version of this project without the serial interface (intend using FT232R module if necessary).

(I use TinyCAD + FreePCB)

I've found that it will only switch to VGA mode if the monitor is connected at power-up.

(I have a switch to use one of my dual monitors - if it is powered up while not switched in it is composite only.)

If all jumpers are in for white text it is quite dim - should use 3 resistors - 1 for each colour.

So far looks promising though.

Phil

Phil -

My purpose in modifying the original design was actually to add the serial interface, and to learn to use KiCAD.

I had considered using SMD's but decided that it wouldn't reduce the size much given the size of the connectors.  Also many hobbyists are more comfortable with thru-hole devices.

You should post pictures of your board!

Geoff Graham's code is available, so you could change it to only support VGA if that is helpful.

Appreciate your comment - I tried KiCad (and a few others) but was not keen.

Not sure what size your board is but looks a bit bigger than mine. I could have added the RS232 parts but I don't use an actual serial port any more. (Plenty of room underneath) Did add 5Vreg to increase power options.

I do have a lot of through-hole components but most are many years old - mostly used on breadboards.

I wanted this to add keyboard and display to a Z80 project and may try it with my 6502 as well if I modify the OS.

Tried to add picture but desn't seem to work here.  Board is 68 x 45mm as part of a 100mm square combined with other projects.

Smallest part was crystal- too small for me these days really- rest were 0805 or better.

Yes the connectors do dominate the board - I could have left off the composite and a USB but would not make a great difference.
I like the way it worked first time though after taking a day to find my PicKit3.
Phil

I have a possible application of this project, but I don't know if I can pull it off.   "Smart TV"'s won't play just audio.  I'd like to play audio through the TV.    I would need to cross convert the PC VGA to TV HDMI externally.  The VT100 device on it's own should give me a "black raster" and possibly a blinking cursor, although no cursor is preferred.  Hopefully, this would satisfy the TV's appetite for video and allow the audio to play.

To take this a step further, I'd like:

"Audio

Only"

to appear on the TV in a different location on the screen every say 5s or so.  Locations could be random, but the direct cursor addressing combined with delete line or clear screen escape code should make this "do able". 

The final goal would be to interrogate a dual tuner with RS232 capability and display something like:

"AM 1380

W???

<Song playing> from RDS data"

I'm looking for an easy way.  Something else like a "Rasberry PI" would be doing the interrogating.

Goal 1: Play Audio only on a "Smart TV"

Goal 2: Get wired Ethernet behind the TV

Goal 3: Repeat the IR remote signals via Ethernet (Commercial product)

Goal 4: Audio over Ethernet

Goal 5: Interrogate and display tuner information.

Those goals would make me really happy. 

This next set of goals would make me even happier.  Mostly for tuner #2.

Goal 1: Stream tuner #2 with VLC (could be easy)

Goal 2: Control Tuner #2 by repeating IR over Ethernet.

Goal 3: Control Tuner #2 via a webpage.

Goal 4: Control Tuner #1 from a webpage.

Some  of the other versions of this project do show the config screens.  This is probably thhe best version I've seen.  Consider taking some pics of the configuration screens.  Not everything, but the basic options.

Did you forget the "bell"?  i.e. Control G, I believe.  I can think of two types ofi mplementations.

1/8" stereo plugs in and out.   Software selectable between "mix bell" and  "bell priority".

"mix bell" would mix the sound of a bell into the audio strean.  "bell priority" would essentially mute what's coming in and just output a "bell sound". A "wav" file might be too much.   A relay to activate a buzzer just doesn't seem right, but it's a third option. 

What kinds of caps did you use? I have these caps laying around:

A - electrolytics, Nichion, for c3, c4, c7 (10uF)

B - tantalums, polarized, for c8, c9, c10, c11, c12 (1uF)

For A, is it a big deal they are not tantalum?

For B, is it a big deal to use tantalums instead of ceramic? Polarity for C8, C9, C10 and C11 is obvious. C12 it should be + on the ground side, other side to -VSS? If not I'll find ceramics.

Electrolytics should be fine for the C3/C4 10uf caps, and are non-critical to value.  C7 is spec'd by microchip as a "10uf typical" low-esr cap.  I suspect most modern 10uf caps would work fine.

The 1uf caps can actually be 0.1uf with the MAX3232 I used 1uf as I have a spool of 3K from a hamfest.  I'm sure your tantalums should work fine and it sounds like  you have the polarity correct.

OK, awesome. Thanks for that!

Actually, I'm going to add a 220k resistor as I have 1.1 boards, and use a Sipex SP202E (pin compatible to MAX232). I'll finish it up and let you know how it goes.

3D Case Design 

- VESA mount support

- VGA port to the right

- Serial port to the left

- USB and Power to the bottom

- Vents along the top

- opening to access the baudrate jumper blocks connectors

Any other requirements? Suggestions?

Mike -

All sound great to me!

Ordered v1.1 boards, and from the comments I understand I need to cut the trace to pin 5 and add a 220k resistor.  Anything other mods?

I will work on a 3D case once I have the board assembled.

I've ordered up some of the Rev 1.1 boards from PCBWay and am looking for footprint-compatible VGA, PS/2, and serial port connectors.  Which ones in particular were used in this design?

Ken -

I picked up the connectors a long time ago thru Aliexpress (back when Chinese shipping was quick and cheap).  All are very standard connectors and available thru Mouser or Digikey. 

Hi Gary,

              I have looked through the Max232 & Pic data sheets. It looks to me that 1k0 would be the smallest value of series reistor to use between MAX232 pin 12 & PIC pin 5,  but to allow for tolerances I would suggest trying a 1k5 and then measuring the voltage on the PIC pin to see if it has dropped to around 3v0 . If this resistor is made too big then it will limit the maximum baud rate on receive.   I haven't built my board yet so can't check the voltage myself.     

To get the voltage at PIC pin 5 to drop to 3.5v took 220K between the MAX232 and PIC.  Good news is that it still works fine at 115.2K baud.  I don't know if it pays to use a voltage divider instead of a simple resistor?  Geoff Graham used 100K to 3.3v and 10K in series.

A single trace cut as pictured above, with a 220K resister added dropped the voltage at PIC32 pin 5 to 3.5v on my board, and seems to work nicely.

I have re-done the PCB to use MAX3232 IC powered by the 3V3 rail.  They have been shipped to me and I'll test them when they arrive.

Hopefully this will be the last revision!

Hi Gary,

             Thank you re comments on the Composite RCA socket & for redesigning the PCB.

However, while checking resistor values I have noticed a subtle error.  Pin 4 & 5 of the PIC are NOT 5V tolerant. Their maximum permitted input in Vdd + 0.3 V ie about 3V6. If you look at Geoff Graham's schematic you will see a 10k resistor in the RxD line between CON1 & pin 5 on the PIC. Geoff says this resistor is there in case a 5V TTL adaptor is plugged into CON1 to protect the PIC pin 5.  The subtle fault I noticed is that RxD (pin12) of the MAX232 is connected DIRECTLY to the PIC pin 5. The MAX232 will output 5V on pin 12. There should be a 10k resistor fitted in this line to protect the PIC pin 5. As the MAX232 IC is fitted I don't think you will be able to use CON1 (unless you pull out the MAX232 IC). Thus you could cut the PCB track from pin 12 of the MAX to pin 5 of the PIC & connect it to CON1 pin 2 & so use the existing 10k resistor.

Another possible solution would be to use the MAX3232 IC powered by the 3V3 rail, as this chip would only put out 3V3 on pin 12. C11 in this case would need to go to 3V3 not 5V.

ARGH, always one more bug.  Thank you for being so observant!

I'll try and edit the pcb this weekend and get a revised board fabricated.

I'm measuring 3.9v on RxD (PIC pin 5), so indeed over the 3.6v max.  It does appear to work fine, but needs fixing!

I assume that putting a 10K resistor between PIC pin 5 and MAX232 pin 12 would do the trick?

I did leave the CON1 option in place, but realize that to use it you'd need to remove the MAX232.

Pretty easy to cut the trace on the V1.1 board and solder a 10K resistor on the back of the board.  I'll get some pictures of the changes up later this weekend.

Have you decided on how the design will change for this fix? Is it a single resistor or a voltage divider? What value(s) are needed?