what values
model Oric-1 from Tangerine Computer Systems
CPU 6502A @ 1 MHz
ROM 16 kB (mine has only IC9, HN613128P ORIC, BASICV1.0, this is a OTP PROM)
RAM 48 kB
Graphics 40 x 28 text, 240 x 200 8 colors
sound AY-3-8912, internal speaker
storage tape recorder, 300 or 2400 baud
operating system Tangerine / Microsoft Extended Basic v1.0
power 9V 600 mA

ports on the back (left to right)

TV output, UHF channel 36 - RCA phono female

RGB output - 5-pin 180 degrees DIN (DIN 45322) connector, female

cassette / sound ouput - 7-pin 270 degrees DIN (DIN 45322) connector, female

printer port - 20 pin 2 rows IDC connector, female

bus expansion port - 34 pin 2 rows IDC connector, female

power connector, 9V center positive

PCB: ORIC-1 Issue 3

other: grey logo

back to my computer history page.


oric.org, Wikipedia Tangerine Computer Systems, Oric-1, DIN connector, Defence Force Forum, Oric video output, RGB to SCART (PDF), Muso's ORIC Site, TheSpider's Oric Web, The Oric Software page, Geoff Phillips' Home Page, Oric World,

more links

RGBtoHDMI, Acorn Electron World: From SCART To Finish, P65Pas - CPU 6502 Pascal Compiler / IDE / Debugger,


CLK - Clock Signal (emulates more than Oric), Oricutron, Emul8D,

local links

local links: GBS-8200 (v4), Skantic B2010HD,


2019-02-25: tested the video buffer with my Skantic B2010HD SCART input (called EXT1 in source menu on the TV). It works as expected, steady and good picture. 0V or 5V on SCART pin 8 (via jumper) - doesn't matter, nothing changes.

2019-02-09: tested the video buffer with the SCART to HDMI converter and a HDMI monitor it works, picture is nice and crisp. 0V or 5V on SCART pin 8 (via jumper) - doesn't matter, nothing changes.

2019-02-09: tested the video buffer with a TV (SCART input). It work, I got a steady and quite good picture. 0V or 5V on SCART pin 8 (via jumper) - doesn't matter, nothing changes.

2019-02-09: video buffer - soldered components on the PCB, ready for testing.

2019-01-08: PCB - milled a new version. This time I got a working PCB in the end.

2019-02-07: PCB - milled a new version of the PCB. Unfortunately, I used the wrong feed settings - 300 mm/min instead of 150 mm/min so the result is useless. Tracks with breaks, rough edges and copper strays shorting tracks etc. New try tomorrow.

2019-02-05: SCART cable - the cables I have are fully wired, which means

1 - 2
2 - 1
3 - 6
6 - 3
17 - 18
18 - 17
19 - 20
20 - 19

all others (including the screen, pin 21) are wired straight through.

2019-02-05: video converter - tested it with a small TV at home. No picture at all.

2019-02-04: video converter - I found another error in my schematic - pin 5 on the input connector (from Oric) J1 is not connected to ground, only to pin 1 of U1. Made a patch wire, tested again, still no change. Could it be that the TV has problems?

2019-02-04: video converter - more testing; tried a different 74HC244 (U1) - no change. Tried a different Q1 - no change.

2019-02-03: Over at stardot.org.uk forums, IanB got Hoglet's RGBtoHDMI working with a ZX81, using a composite video adapter he made. Interesting.

2019-02-02: soldered a patch wire from pin 16 to the right place, and isolated pin 18. Now at least I get a picture on the SCART TV, but it is rolling (vertical sync not stable). The SCART to HDMI converter still shows no picture.

2019-02-02: I tested the video buffer, both with a SCART TV, and with a SCART to HDMI converter. Unfortunately I get no pictiure. Looking at the schematic, I see an error: I have connected the blanking signal to pin 18 of the SCART connector - but it should be connected to pin 16 (pin 18 is ground signal for the pin 16).

2019-02-01: I soldered components to the video buffer PCB. for C1 I used a 10 uF electrolytic capacitor, and I used BC547 (BC547B) instead of BC548 for the transistors.

2019-02-01: I milled a PCB for the video output buffer described in Oric video hardware.

2019-01-18: video output - we have 74HCT244 at Bitraf.

2019-01-18: power on test - I found a 9V psu at Bitraf, and tested the Oric-1 (without picture). The command PING, ZAP, SHOOT work, so the machine is working (to some degree at least).

2019-01-18: the 5-pin DIN plug fits the RGB connector, it is for soldering wires to the pins.

2019-01-17: eBay - the package with the DIN plugs arrived.

2019-01-09: RGB connector pinout

1 red
2 green
3 blue
4 sync

I'm guessing sync is composite sync.

2019-01-08: I ordered some DIN connectors (male) from eBay.

2019-01-08: psu - the power supply is missing.

2019-01-08: I created the first version of this page.