Lpc2000

--- In lpc2000@yahoogroups.com, "catstransport" <remco@u...> wrote:
> I have a small problem with the wait states of the tl16c754. I have
> made a test method for writing and reading to some addresses. To the
> address of lcr i can write and read. But to the address of mcr I can't
> write or read to it. Both have the possebility to read and write. When
> The cs and bls signals are working when I write 0xaa and 0x55 to the
> quad uart.I look at the address lines and data lines by scope I see
> that the lines are triggered.
> I think that it has to do with the wait states. Now the BCFG register
> is set to 0x0000ef8f. With a maximum WST1 and WST2 wait state and IDCY
> to it's maximum. I have tried to set the AURT and just write a
> character to it but that doesn't work. Has anyone a solution for this
> problem.
> I have tried to changing some wait states but still i have this issue.
> Can somebody help me with this issue.

Wait States is not the problem. We are using the same chip and after
stuffing around for a couple of weeks we finally found that the device
is in some legacy mode. The address lines are ignored and one need to
access it in a 2 step process. First write the address to device.
(i.e. Address of register in data byte) The next access then reads or
writes the data from the register pointed to by the first access. 
Please contact TI regarding this matter. When we contacted them we got
a very unsatisfactory reply. Hopefully if more people complain about
this, they would fix the device or provide a way to switch so that it
works as specified in the datasheet.

Regards
  Anton Erasmus