>
>
> Hi,
>
> I seem to have the same problem... I'm using a "barebone" CY7C68013A board
> without any drivers (i.e. the PBx pins are directly connected to the DUT).
> When one of the PB pins samples a "1", this level is output still after
> sampling.
>
> Actually, I had the issue when I was preparing the ATMEGA32 SPI dumps: The
> SPI and the in-circuit programming pins are the same and I wasn't able to
> use the ATMEL programmer after capturing the SPI signals. I thought the SPI
> signals may have tripped up the programmer but seems above mentioned
> behaviour is the culprit.
>
> I am no CY7C68013A expert but according to the datasheet Port B has tri
> state functionality => So it should be possible to set the pins before &
> after acquisition accordingly, we "only" need to find the correct place in
> the firmware...
>
In fact the default state of the port control register is tristated. You
can easily verify that PB0-PB7 are tristated right after reset or right
after you connect the CY7C68013A to the USB port. It is *after* the fx2lafw
firmware is loaded by sigrok and an acquisition is run that PB0-PB7 are
left configured as output. I would be surprised if it was not caused by a
bug in the fx2lafw firmware.

The problem here is that IMO this is a very serious bug because it is
causing an electrical conflict on the PB0-PB7 pins on *every* CY7C68013A
based analyzer out there in which the fx2lafw firmware is being used, and,
most importantly, *it is being unnoticed,* because the DUT won't be
disturbed as long as you have an intermediate input buffer like almost all
logic analyzers have. The electrical stress will eventually cause failure
of one or several I/O pads.

Regards.








> Regards - Clemens
>
>
>
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