PICDREAM II VIDEO PAL GENERATOR

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F1CJN_alain
Posts: 90
Joined: Thu Jul 21, 2011 9:50 am

PICDREAM II VIDEO PAL GENERATOR

Post by F1CJN_alain » Fri Jan 12, 2018 10:11 am

After PICDREAM (20 years !) my new color PICDREAM II is on GITHUB.
- uses a PIC24F16KA101 and an AD724.
- text, colors and background (bars or pseudo SMPTE ) programmable via serial link(or USB) via adaptor
- EEPROM memorization of 2 lines of scrolling or non scrolling texts
- EEPROM memorization of text colors and backgrounds
- the board may plug in on an Arduino Uno for home or repeater messages.

I have put the user manual, schematic, software and board files on GITHUB.https://github.com/F1CJN/PICDREAM-II
An old first video was post on Youtube. https://www.youtube.com/watch?v=cSjej2kyfBw

Have fun
Alain F1CJN

G4FRE
Posts: 197
Joined: Fri May 26, 2017 6:57 am

Re: PICDREAM II VIDEO PAL GENERATOR

Post by G4FRE » Fri Feb 23, 2018 9:44 pm

Hi Alain

What are the PIC chip configuration settings needed for picdream II? I just have to programme the chip to try mine out

73
Dave
G4FRE
Attachments
picdream2_cfg.jpg
picdream2_cfg.jpg (83.88 KiB) Viewed 5671 times

F1CJN_alain
Posts: 90
Joined: Thu Jul 21, 2011 9:50 am

Re: PICDREAM II VIDEO PAL GENERATOR

Post by F1CJN_alain » Thu Mar 15, 2018 11:43 pm

Sorry for the late answer, due to very far and long vacations ;) .
The configuration is included in the .hex file.
So if your are using a Pickkit 3, just load the .hex file after declaring the chip name.
73's
Alain F1CJN

G8AGN
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Joined: Mon Mar 05, 2018 1:41 pm

Re: PICDREAM II VIDEO PAL GENERATOR

Post by G8AGN » Fri Mar 16, 2018 8:05 am

Alain

Do you have any bare pcbs for this project?

73

Barry, G8AGN

G8GKQ
Site Admin
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Re: PICDREAM II VIDEO PAL GENERATOR

Post by G8GKQ » Fri Mar 16, 2018 12:03 pm

Barry

Please see Dave, G4FRE's post in "For Sale" below.

Dave, G8GKQ

G8AGN
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Joined: Mon Mar 05, 2018 1:41 pm

Re: PICDREAM II VIDEO PAL GENERATOR

Post by G8AGN » Fri Mar 16, 2018 1:10 pm

Dave

Many thanks.

Barry

G4FRE
Posts: 197
Joined: Fri May 26, 2017 6:57 am

Re: PICDREAM II VIDEO PAL GENERATOR

Post by G4FRE » Fri Mar 16, 2018 6:06 pm

Alain
what software are you using to connect the pickit 3 to the computer? I have tried mplab-x without success

73
Dave

F1CJN_alain wrote:
Thu Mar 15, 2018 11:43 pm
Sorry for the late answer, due to very far and long vacations ;) .
The configuration is included in the .hex file.
So if your are using a Pickkit 3, just load the .hex file after declaring the chip name.
73's
Alain F1CJN

G8AGN
Posts: 34
Joined: Mon Mar 05, 2018 1:41 pm

Re: PICDREAM II VIDEO PAL GENERATOR

Post by G8AGN » Wed Mar 28, 2018 2:59 pm

Dave, G4FRE, kindly sent me a pcb for the PICdream2 and so it's now built up and working. I opted to use a DIL socket on the pcb for the PIC and to program it using a PICKit3 and the hex file V1c.production which is included in the GitHub download. I did not use the in circuit programming feature but it should work OK.

There are a few errors in the notes and on the silkscreen printing on the pcb

1. The notes refer to J1 as being the USB/TTL interface header. It should be J5.

2. The pins on J5 are labelled incorrectly. Tx should be Rx and vice-versa (see circuit diagram)

Here are a few comments about programming the video output.

1. I'm using the Termite terminal software, v3.4. This should be set to 38400,8,N,1,N and make sure in the Settings menu to select CR-LF to be sent at the end of a command.

2. On first powering up the PICdream2, it should display a preset picture with both scrolling and fixed text and two types of colour bar.

3. To tell the PIC that you want to start programming the display, hit Return on the terminal and it should show a response asking for further input. Try typing <help> and Enter (which will add CR+LF). A list of commands should now be shown. Enter these in turn as desired to give the required video output. I found it useful to connect a colour monitor to the PICdream2 output while programming to check that the display was as I wanted it.

3. I've found two undocumented commands
<smpte>bk and <bar>bk turn off either the SMPTE or secondary colour bars, respectively.

4. When you are satisfied with the video display, it can be saved using the <w> command as detailed in the notes.

5. So far I have not managed to program PICdream2 using an Arduino. The example sketch in the notes gives a compilation error but this can be corrected by moving the closing brace } in void setup{} down by one line in the sketch listing. I don't know whether the mySerial.write commands are correct as they use the special character \r which is just CR rather than CR+LF

Hope these comments will be of use to others.

73

Barry, G8AGN

G8AGN
Posts: 34
Joined: Mon Mar 05, 2018 1:41 pm

Re: PICDREAM II VIDEO PAL GENERATOR

Post by G8AGN » Sat Mar 31, 2018 2:14 pm

I forgot to mention in my previous post that when building up the PICdream2 on Alain's design of PCB, you should ensure that the xtal cans do not actually touch the xtal mounting pads as that can short the xtals - an obvious point maybe but worth checking if nothing works on first switch-on.

Barry

G4FRE
Posts: 197
Joined: Fri May 26, 2017 6:57 am

Re: PICDREAM II VIDEO PAL GENERATOR

Post by G4FRE » Sat Mar 31, 2018 9:51 pm

With the hint from Barry about insulating the crystals I got my Picdream II working.
Like Barry, I also programmed the IC in an external programmer. I tried the ICSP port on the PCB but the PICKIT went into overcurrent alarm as it was powering the whole PCB, not Just the PIC

The only other issue I had was with the USB to serial converter. If your USB interface produces +3.3V levels you can connect it to J5 and the unit works. If your USB interface produces +5V levels, connect it to j2 and the unit works (the clue to this was that the Arduino Uno is 5v and uses J2). If you connect the +5V levels to J5 the unit doesn’t come out of reset, and run the program.This is because these sort of USB interfaces idle at +volts so the pic has +5V on the serial input but only 3.3V on its supply rail so it latches up. Luckily no damage was done! Failing having the documentation, It is easy to tell which level you have by using a voltmeter to measure the TXD out voltage from the usb adaptor. It will be +5 or +3.3V. If its near 0V the level is inverted and the interface cannot be used (I know… I tried using the interface off my kx3 which does this)

Dave
G4FRE
Attachments
picdream2.jpg
picdream2.jpg (1.42 MiB) Viewed 5030 times

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