If you want to ask questions about how the machine works, peculiar details, the differences between models, here it is !
How to program the oric hardware (VIA, FDC, ...) is also welcome.
I have two Microdisc and three Atmos. Recently I built a power supply for them, with one jack and two 4 pin DIN connectors (Microdisc style), the PS go out 7.5V 2A and 15V 1A. When I connect Atmos, Microdisc and PS, the Atmos don't boot, all I can see is a screen full of trash.
Yes, i tried without the Atmos' PSU too and the Microdisc power the Atmos thru the expansion port, but same results. I forget to say that the two Microdisc don´t work on the three Atmos.
Hi
I had problems when I rebuilt a couple of drives a few years back and steve marshall sorted me out so you could drop him an email ,from memory your dil switches look in the wrong position on your controller I maybe wrong but its worth a try on row 'A' mine had to be set to 1 on,2 off 3 off 4 off 5 on or off depending on version.
row 'B' 1 off ,2 on 3 off ,4 off others not used
maybe somone still with a drive could confirm this
When i press the reset button nothing happen, some times the pattern on screen change, other times no. I tested the flat cables and all ok, i think the problem can be with signal integrity (Phi2) and others, and a unshielded flat cable.
kenneth wrote:the IC5 pin 2 signal has a strange shape.. Normally phi2 provides a square signal shape and a "pull up" resistor of 3.3k is there for that.
The 3K3 pull up resistor is lost in my two Microdisc, i'll put them and i'll see the wave again. Also, the IC5 pin 2 signal has a level of, 3 squares * 2 volts per square = 6 Volts???? Mmmm strange.
The voltage can go beyond 5v if there is a floating potential ( command by a transistor with an "open collector" ) and add a capacitor... the oscilloscope for example !