P1V i/o pin settings
rjo__
Posts: 2,114
in Propeller 1
I am working on a camera interface for the p1v for Omnivision cameras. Everything was going swimmingly until I hooked a camera up to it:)
That was more than a couple of months ago. Naturally I assumed first that I had a verilog problem...many months of fiddling and head scratching lead me to conclude that my verilog was probably not the problem. I then went back to working with the interface on a Propeller Activity Board. I created software to identify which camera was attached to the P1 and to evaluate signals coming from it... lot's of fun, works great. However when I use exactly the same camera ... OV7670 and exactly the same software on a P1v, the only thing that works is the i2c interface and the pixelclock coming from the camera.
I abandoned my verilog project and returned to a verilog version that included just the P1v, using the de2-115 with Parallax's add-on board... and to my surprise, I had the same problem(Good i2c, good pixelclock... bad H and V sync. In Quartus II, pin i/o standards are quite complete. I am using 3.3v LVTTL with maximum current... after this mind numbing experience, it has occurred to me that this standard might not match the real silicon P1's pin performance.
Any help would be appreciated.
Thanks,
Rich
That was more than a couple of months ago. Naturally I assumed first that I had a verilog problem...many months of fiddling and head scratching lead me to conclude that my verilog was probably not the problem. I then went back to working with the interface on a Propeller Activity Board. I created software to identify which camera was attached to the P1 and to evaluate signals coming from it... lot's of fun, works great. However when I use exactly the same camera ... OV7670 and exactly the same software on a P1v, the only thing that works is the i2c interface and the pixelclock coming from the camera.
I abandoned my verilog project and returned to a verilog version that included just the P1v, using the de2-115 with Parallax's add-on board... and to my surprise, I had the same problem(Good i2c, good pixelclock... bad H and V sync. In Quartus II, pin i/o standards are quite complete. I am using 3.3v LVTTL with maximum current... after this mind numbing experience, it has occurred to me that this standard might not match the real silicon P1's pin performance.
Any help would be appreciated.
Thanks,
Rich
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