ColdFire/68K Microcontrollers and ProcessorsのトピックRe: MCF52235: EzPort write enable

MCF52235: EzPort write enable

Petter — Thu, 29 Oct 2020 08:45:49 GMT

I can read FLASH data through the EzPort just fine. However, if I try
to set the write enable bit by issuing a WREN(0x6) command, the status
register read back using RDSR(0x5) does not return anything but zero.
As you see from the enclosed analyzer waveforms I send 0x06, 0x05, and
0x00 (EZBYTE1,2, and 3) but the output is zero.

I've also tried to do a RDSR in a loop, but I still only get zero as
output. I have no problem of issuing a READ(0x3) to read data from the
FLASH. I'm using the M52235EVB board. Any ideas or pointers to
documentation/erratas?

Re: MCF52235: EzPort write enable

Petter — Wed, 12 Sep 2007 01:55:33 GMT

I'll try to upload the waveforms again...

Re: MCF52235: EzPort write enable

Petter — Sun, 16 Sep 2007 22:16:46 GMT

The reason was that I did not release RCON* after I asserted it initially. In this mode I could read the FLASH just fine, but not do any writes to the control register. I can now both read and write to the FLASH from the EzPort.