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-   -   Karen's PICL - PCB available (https://www.vintage-radio.net/forum/showthread.php?t=181338)

Phil__G 23rd Jun 2021 2:50 pm

Karen's PICL - PCB available
 
4 Attachment(s)
I've just done a PCB for Karen's 2007 PICL design, which is an SC/MP emulation in a PIC, running the genuine National NIBL interpreter code from 1976.
Karens emulation is cycle-perfect and enables a two-chip genuine NIBL machine to be built very cheaply and easily.
The PCB is under 3" square and has all the Flag and Sense lines brought out to LEDs, buttons and a header, and talks via the usual USB-to-serial CH340 module. The chips are a 6264 static RAM and a PIC16F877 (not sure in an '877A' will work).

For anyone fancying a look at NIBL or a trip down memory lane, this computer is really cheap, quick & easy to make. Its nice to make one of Karens many projects as a tribute to all she achieved.

Here's a video: https://www.youtube.com/watch?v=Hv-_9tpXeqA

The channel also has a video of the strip-board version, another running a Geoff Graham terminal chip and one using a re-coded Xbox chatpad keyboard.

Ultimately I'll post the gerbers but first I need to check some changes I made for the next batch (If there is a next batch!). The change is minor, just repositioning the serial board so its flush against the edge of the PCB. Its electrically identical but I'd like to test one first.

If anyone would like a board, please email me rather than use the forum and I'll send a PCB at cost. If I run out, I'll order more, takes a couple of weeks. This is at cost, strictly non-profit.

Here's Karens PICL page: http://techlib.com/area_50/Readers/Karen/micro.htm#PICL

Cheers
Phil email: рhіlg@tаlk21.соm
Note that to avoid spam, the address above is unsearchable text & can't be copy-&-pasted into the 'to' field !

Timbucus 23rd Jun 2021 9:19 pm

Re: Karen's PICL - PCB available
 
Phil,

That is so cool - I actually watched and liked that video last night... the more you look into Karen's work the cleverer it becomes.

Great to see a PCB like this - a real service for those who want to play.

Any chance you will be making an Orton View PCB :) ?

Tim

Quote:

Originally Posted by Phil__G (Post 1384769)
I've just done a PCB for Karen's 2007 PICL design, which is an SC/MP emulation in a PIC, running the genuine National NIBL interpreter code from 1976.
Karens emulation is cycle-perfect and enables a two-chip genuine NIBL machine to be built very cheaply and easily.
The PCB is under 3" square and has all the Flag and Sense lines brought out to LEDs, buttons and a header, and talks via the usual USB-to-serial CH340 module. The chips are a 6264 static RAM and a PIC16F877 (not sure in an '877A' will work).

For anyone fancying a look at NIBL or a trip down memory lane, this computer is really cheap, quick & easy to make. Its nice to make one of Karens many projects as a tribute to all she achieved.

Here's a video: https://www.youtube.com/watch?v=Hv-_9tpXeqA

The channel also has a video of the strip-board version, another running a Geoff Graham terminal chip and one using a re-coded Xbox chatpad keyboard.

Ultimately I'll post the gerbers but first I need to check some changes I made for the next batch (If there is a next batch!). The change is minor, just repositioning the serial board so its flush against the edge of the PCB. Its electrically identical but I'd like to test one first.

If anyone would like a board, please email me rather than use the forum and I'll send a PCB at cost. If I run out, I'll order more, takes a couple of weeks. This is at cost, strictly non-profit.

Here's Karens PICL page: http://techlib.com/area_50/Readers/Karen/micro.htm#PICL

Cheers
Phil email: рhіlg@tаlk21.соm
Note that to avoid spam, the address above is unsearchable text & cant be copy-&-pasted into the 'to' field !


SiriusHardware 23rd Jun 2021 10:49 pm

Re: Karen's PICL - PCB available
 
Agreed, a nice job by Phil and a great tribute to Karen who no doubt would have been very pleased to have seen this. It's great to see that she is still motivating new builds and new projects after she so sadly left us last year.

You're probably better off emailing Phil for a more immediate response and further information, he's made it fairly clear that he regards his presence here as sporadic at best.

I'm going to stay hands off on this one because I am trying to thin my stuff down rather than acquire more of it, but I will remain an interested observer as always.

For an OrtonView PCB we might need to look to someone who is already incentivised by owning an issue VI replica, the version best suited to working with original SOC VDUs and Ortonview which was intended as a one for one substitute for the SOC VDU. I think it would also make sense for it to include the 1.5K memory expansion (for which the issue VI already has the memory hole) because the VDU is barely usable on a 640 byte MK14, it really needs to have 512 continuous bytes of additional RAM dedicated to it.

Slothie 27th Jun 2021 9:56 am

Re: Karen's PICL - PCB available
 
I've been thinking about doing an ortonview PCB with memory expansion and a couple of other bits, and to allow me to tinker with the firmware because I have tried over the last few months a couple of times but my breadboard implementation is so unreliable its impossible to decern software problems from loose wires!
Phils PICL board looks great, I'd be tempted if I didn't already have 4 or 5 projects on the go.... Its certainly very smart looking, I feel Karen would approve (although it lacks a hand-crafted case to contain it!!)

SiriusHardware 27th Jun 2021 10:10 am

Re: Karen's PICL - PCB available
 
Yes, for those of us who are complete Klutzes at metalwork and woodwork, we need a commercially produced hand crafted enclosure. ;)

Mark1960 27th Jun 2021 6:59 pm

Re: Karen's PICL - PCB available
 
Quote:

Originally Posted by SiriusHardware (Post 1385753)
Yes, for those of us who are complete Klutzes at metalwork and woodwork, we need a commercially produced hand crafted enclosure. ;)

Just pick a case and design the pcb to fit that case. There are a few cases that would allow the front panel to be a pcb, which does limit the front panel color options but avoids the need for any metalwork or woodwork.

ParcGwyn 3rd Jul 2021 7:11 pm

Re: Karen's PICL - PCB available
 
1 Attachment(s)
Very nice, a lot more professional than my matrix board.

Dave
GW7ONS

Timbucus 3rd Jul 2021 10:57 pm

Re: Karen's PICL - PCB available
 
Oh nice another one built and working - is that a VT100 terminal board below?

ParcGwyn 4th Jul 2021 3:49 pm

Re: Karen's PICL - PCB available
 
Quote:

Originally Posted by Timbucus (Post 1387486)
Oh nice another one built and working - is that a VT100 terminal board below?

I made the terminal a few years ago, specifically to use PICL, on a piece of matrix board. I think it this one: https://www.serasidis.gr/circuits/TV...V_terminal.htm but can't be certain.

Dave
GW7ONS

Slothie 4th Jul 2021 5:24 pm

Re: Karen's PICL - PCB available
 
1 Attachment(s)
I know I said in comment #4 above I had too many projects on the go, but Phil was kind enough to send me a PCB anyway and I had most of the components required left over from other projects, so I've spent my birthday weekend putting it together. The only parts I was short were the 1/8w resistors, the CH340 serial board (I had other types but not the one that would plug straight in) and the Memory chip. I ordered the bits last week and all the bits arrived my Saturday aside from the memory chip, but that will probably be here monday. Its looking nice, I just need a teeny terminal to go with it! I also need to dig out my PIC programmer and program one of my spare 16F877's.

Timbucus 5th Jul 2021 1:35 pm

Re: Karen's PICL - PCB available
 
1 Attachment(s)
I also have to thank Phil as he sent me a board - I am putting together a kit to build it but, I thought you may all appreciate a photo of me powering up the original prototype which was included in the Orton collection I now curate...

Attachment 237113

.. it is also in the YouTube video - not actually powered up at this point as well...

https://www.youtube.com/watch?v=mZY5Q_jzRxs&t=2785s

Slothie 5th Jul 2021 7:45 pm

Re: Karen's PICL - PCB available
 
My RAMs arrived today, and my PICL is fully-functional. I still need to get the settings right for 'minicom' for uploading programs, it seems a bit sensitive, sometimes I get load errors and other times I don't. I also find if I edit captured files to re-upload they don't always load, so their might be spurious characters getting inserted by vi. Maybe I need to tinker with the settings more! I did also think if there is space on the microcontroller then some kind of buffer could be implemented to ease the flow control problems, but that would be an experiment for another day.

I also am finding the LEDs a bit bright, so I could have used the 470 ohm resistors I had rather than the 330 ohm resistors I bought, so if others are building one then I'd suggest experimenting with the value before soldering everything in.

Now I'm just thinking of ideas of what to do with it!

Slothie 5th Jul 2021 7:50 pm

Re: Karen's PICL - PCB available
 
Here's a program to calculate 'e' (the base of natural logarithms) to arbitrary numbers of significant digits (set by the variable N in line 100).
Code:

100N=20:X=TOP:Y=TOP+N
110FORI=0TON-1:@(X+I)=0:@(Y+I)=0:NEXTI
120@Y=1:D=1:DO
130 U=0
131FORI=N-1TO0STEP-1
132U=U+@(X+I)+@(Y+I)
133@(X+I)=MOD(U,10)
134U=U/10
135NEXTI
140PR@X,".";:FORI=1TON-1:PR@(X+I);:NEXTI:PR""
150U=0:V=0
160FORI=0TON-1:U=U*10+@(Y+I):@(Y+I)=U/D:U=MOD(U,D):V=V+@(Y+I):NEXTI
170IFU>D/2@(Y+N-1)=@(Y+N-1)+1
180D=D+1:UNTILV=0

I modified this from the version on the page https://www.quinapalus.com/psb.html which shows a LPC811 version based on the PICL.

SiriusHardware 5th Jul 2021 8:24 pm

Re: Karen's PICL - PCB available
 
I don't know if Minicom does, but programs like Hyperterminal (Windows) can open and send a text file and there are advanced settings for inserting extra time between transmitted lines and between transmitted characters.(Forgive my ignorance but I am assuming that what you are trying to upload is essentially the text you would type in if you were entering the code manually).

Slothie 5th Jul 2021 8:41 pm

Re: Karen's PICL - PCB available
 
Quote:

Originally Posted by SiriusHardware (Post 1387898)
I don't know if Minicom does, but programs like Hyperterminal (Windows) can open and send a text file and there are advanced settings for inserting extra time between transmitted lines and between transmitted characters.(Forgive my ignorance but I am assuming that what you are trying to upload is essentially the text you would type in if you were entering the code manually).

Yes, you can in minicom too. With a 500mS delay after each line and 50mS delay between characters its reasonably reliable, but that is slow so I need to tune it some!

SiriusHardware 5th Jul 2021 9:26 pm

Re: Karen's PICL - PCB available
 
I wonder if this is a bit like the ZX81, where the screen update after each line entry gets slower and slower the more lines there are? If so, you would have to make the inter-line delay the maximum that it is ever likely to have to be, which in the early stages of transmission would waste a lot of time.

For optimum upload speed the system probably really needs a serial 'Wait, I'm busy' handshaking line in addition to TX/RX/GND.

Failing that, maybe write a bit of Python to open the text file and send it to the serial port character by character (at timed intervals if necessary) but with an increasing delay after sending each successive line. You could also have it strip out any unwanted non-printable characters which may have been introduced at the capture / edit stage.

Mark1960 5th Jul 2021 11:43 pm

Re: Karen's PICL - PCB available
 
If the interface to NIBL is full duplex, could you wait for each character to be echoed before sending the next character?

Slothie 5th Jul 2021 11:52 pm

Re: Karen's PICL - PCB available
 
Quote:

Originally Posted by Mark1960 (Post 1387954)
If the interface to NIBL is full duplex, could you wait for each character to be echoed before sending the next character?

The interface doesn't echo characters back unfortunately!

Since the serial I/O of the PICL is done by the PIC rather than bit-banged by the SC/MP as in the original, it may be possible to change the emulator to do flow control and buffering, or even just echo back the characters, without having to change the NIBL code.
I'd also like to build in a lower-case -> upper-case conversion just for convenience! Its going to be on the lower part of my to-do list however!

Timbucus 6th Jul 2021 1:23 am

Re: Karen's PICL - PCB available
 
Of course most of Karen's later projects were aimed at overcoming this problem with NIBL - this entry in HomeBrew is relevant... https://www.vintage-radio.net/forum/...d.php?t=168499

Phil__G 23rd Jul 2021 2:10 pm

Re: Karen's PICL - PCB available
 
1 Attachment(s)
The second batch of PICL PCBs have just arrived this morning, I've a couple spare if anyone is interested. I took the opportunity to to flip the CH340G serial board so its component-side up, and to move it in a few mm so its flush with the overall outline. The pcb has corner mounting holes - otherwise its identical to the previous board. Functionally its identical.
If anyone would like a board, please email me rather than use the forum and I'll send a PCB at cost. If I run out again, I can order more, no problem. This is at cost, strictly non-profit.

Regarding loading programs, at 1200 baud NIBL does need a line delay of say 300ms and a few ms of character delay, thats just how it is.
Even with generous delays, its faster than its original 110 baud and less error-prone than typing, and is probably as fast as a typical tape interface was back then... :thumbsup:

Cheers
Phil email: рhіlg@tаlk21.соm
Note that to avoid spam, the address above is unsearchable text & can't be copy-&-pasted into the 'to' field !


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