Jim Strickland
2014-01-01 19:00:45 UTC
I have a question about my parportprop board on my zeta. I had assumed that
its somewhat dim performance on my LCD was because it wasn't driving the
LCD at its native frequency. To that end, I got my hands on a Sony
multisync trinitron over the holiday and hooked it up. I got the same dim
output. I have also tested the monitor with a PC vga board and gotten
normal bright colors, so my question is, are others seeing this?
Looking at the VGA spec, I see that my initial hypothesis that a 3.3v
propeller can't generate the 5 volt signals for the vga standard is
rubbish. The vga spec is 0.7v p-p. I am now wondering if my substitution of
slightly higher resistances in the last stage of the DAC resistors is
what's biting me. I've not tested the output voltages, so it could be
something else entirely. Suggestions?
-JRS
its somewhat dim performance on my LCD was because it wasn't driving the
LCD at its native frequency. To that end, I got my hands on a Sony
multisync trinitron over the holiday and hooked it up. I got the same dim
output. I have also tested the monitor with a PC vga board and gotten
normal bright colors, so my question is, are others seeing this?
Looking at the VGA spec, I see that my initial hypothesis that a 3.3v
propeller can't generate the 5 volt signals for the vga standard is
rubbish. The vga spec is 0.7v p-p. I am now wondering if my substitution of
slightly higher resistances in the last stage of the DAC resistors is
what's biting me. I've not tested the output voltages, so it could be
something else entirely. Suggestions?
-JRS
--
You received this message because you are subscribed to the Google Groups "N8VEM" group.
To unsubscribe from this group and stop receiving emails from it, send an email to n8vem+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/***@public.gmane.org
To post to this group, send email to n8vem-/JYPxA39Uh5TLH3MbocFF+G/***@public.gmane.org
Visit this group at http://groups.google.com/group/n8vem.
For more options, visit https://groups.google.com/groups/opt_out.
You received this message because you are subscribed to the Google Groups "N8VEM" group.
To unsubscribe from this group and stop receiving emails from it, send an email to n8vem+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/***@public.gmane.org
To post to this group, send email to n8vem-/JYPxA39Uh5TLH3MbocFF+G/***@public.gmane.org
Visit this group at http://groups.google.com/group/n8vem.
For more options, visit https://groups.google.com/groups/opt_out.