topic Re: LPC8xx EEPROM Emulation in LPC Microcontrollers

LPC8xx EEPROM Emulation

LArmstrong1985 — Mon, 31 Oct 2016 14:57:35 GMT

Hi,

I tried the official example for LPC8xx EEPROM Emulation attached here.

For me it doesn't work because in Debug mode, if I unpowered the board and I execute the firmware,

I don't read the written value on page started from 0x1000.

What am I doing wrong?

Thank you very much!

Original Attachment has been moved to: LPC800-EEPROM-emulation.zip

Re: LPC8xx EEPROM Emulation

jeremyzhou — Tue, 01 Nov 2016 01:07:46 GMT

Hi Fabio Benevento,

After had a brief look through the description, I still have some queries.

1. I was wondering if you can tell me the whole steps of testing the demo on the board.

2. Can you explain the meaning of the "if I unpowered the board and I execute the firmware"?

Have a great day,
Ping

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Re: LPC8xx EEPROM Emulation

LArmstrong1985 — Wed, 02 Nov 2016 08:48:06 GMT

Hi Jeremyzhou,

I executed the demo in debug mode. Until I keep powered the demo board

with usb and I rerun the demo I read the value written in flash the first time.

If instead, between an execution and the other, I unpowered the demo board

when I rerun the demo in debug mode I lost the written data and I read 0xFF

for all byte in the area in 0x1000.

I hope I was clear.

Thank you in advance.

Fabio

Re: LPC8xx EEPROM Emulation

jeremyzhou — Thu, 03 Nov 2016 06:30:06 GMT

Hi Fabio Benevento,

I think I'm clear with the issue: the written value will disappear after you return the debug mode no matter keep power persistently or not.

The 0x1000 area is occupied by the demo, in another word, the area will always be erased and programmed when enter the debug mode.

Hope it helps.
Have a great day,
Ping

Re: LPC8xx EEPROM Emulation

LArmstrong1985 — Thu, 03 Nov 2016 09:37:20 GMT

Hi Jeremyzohu,,

the address 0x1000 is the address proposed by the demo, but I've also tried other address like 0x2000 with same

results.

Moreover, if I see the bin size is 0x9b4 then 0x1000 is a free area.

What tool have you used for view the memory footprint? I've ever used the memory view but only when I'm in debug mode.

Anyhow do you have another example that store persistently a group of value in flash?

Thank you in advance.

Fabio

Re: LPC8xx EEPROM Emulation

jeremyzhou — Fri, 04 Nov 2016 12:23:17 GMT

Hi Fabio,

I've run the demo on the LPCXpresso 812 MAX with two kinds of IDE: KEIL and LPCXpresso.

It both can works well.

In my testing, the address is changed to the 0x2A00.

Using the LPCXpresso:

1. In the firstly cycle , enter the debug mode.

2. Enter the debug mode after re-power the board.

And the same result is happen when using the KEIL.

Hope it helps.
Have a great day,
Ping