8-bit Microcontrollers中的主题 Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Fri, 26 Jul 2013 19:42:57 GMT

I am using the examples from AN4570. The example "EEPROM_ProgramUpto4Bytes". I am writing to location 0x3100 and the data is visible when using the "Memory Monitor" but when the chip is reset the data goes back to 0xFF. I am erasing before writing and the functions are returning success. I am assuming that the BUSCLK is the 4MHz crystal that is clocking the chip (the datasheet is vague about this) so I have set FCLKDIV to 0x03 (3.6 to 4.6MHz). Any ideas on what I'm doing wrong?

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

pavel_sadek — Sun, 28 Jul 2013 09:48:40 GMT

Before command write sequence, NVM_FCLKDIV should be written to configure the flash clock to be between 0.8 and 1MHz.

be sure you are running the routine from RAM.

Pavel

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

Monica — Wed, 07 Aug 2013 01:24:01 GMT

Hello Gregory,

was this helpful? Please let us know :smileyhappy:

Best,

Monica.

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Wed, 07 Aug 2013 13:16:13 GMT

I have not been able to try running from ram but I believe that was my issue.

Thank you all!

Re: Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Tue, 13 Aug 2013 16:28:51 GMT

I have been trying to run the code in ram but have run into a problem. When I uncomment the lines that copy flash to ram, the debugger fails to launch. I get the error shown in the attached image (EEPROM_ERROR_DEBUG.png).

I am attaching the project that is giving me the issues. The copy lines are in the file hal_eeprom_init.c. Lines 58 and 60.

The chip that I'm running this on is a MC9S08PA4. There is only 512 bytes of ram. The two functions (erase and write) are a total of 204 bytes. I am left with a very small amount of RAM. Could I use the same ram space and copy the functions in as I need them?

Thank you in advance!

Re: Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Tue, 13 Aug 2013 18:19:22 GMT

Is it possible to just have the code

NVM_FSTAT = 0x80;

while (!(NVM_FSTAT & NVM_FSTAT_CCIF_MASK));

run in ram rather than the complete functions? This seems to be the only time that the eeprom is accessed and it would help me with my memory constraints.

Thanks again!

Re: Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

pavel_sadek — Wed, 14 Aug 2013 07:34:47 GMT

you can use just this fragment in RAM

be sure interrupts are disabled during this operation

Pavel

Re: Re: Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Wed, 14 Aug 2013 20:07:28 GMT

I have used just that small bit of code

NVM_FSTAT = 0x80;

while (!(NVM_FSTAT & NVM_FSTAT_CCIF_MASK));

and loaded it into an array that I call from the erase and write routines and it is still not writing the eeprom (I still see the values there when I write but when I power cycle it, the values are not retained).

Also, I am having problems with the debugger (https://community.freescale.com/thread/310757). This kind of issue keeps coming up. While I'm working on this code it will go off and say that it can't show the disassembly for the current instruction. Sometimes it just completely loses connection to the micro and needs to be started again. Any idea why I can't write the eeprom and why the debugger is doing this?

Thank you in advance!

Re: Re: Re: Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

pavel_sadek — Thu, 15 Aug 2013 12:26:29 GMT

I have ran your code on my PT60 TWR board - it is failing in hal_clk_init function,

I have excluded

// ICS_OSCSC_OSCOS= 0x01; // Output Select (1 Oscillator clock source is selected)

// while (ICS_OSCSC_OSCINIT == 0); /* waiting until oscillator is ready */

and flashed those 4 bytes into EEPROM space 0x3100

then I did a POR (I have disconnected the board completely to be sure)

and launched the code again with breakpoint at the beginning of main

the content of EEPROM is correct

this ICS setup seems to be the source of an issue of your debugger too.

I hope this will help

Pavel

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Thu, 15 Aug 2013 14:52:43 GMT

I did comment out those two lines but my experience was very different.

Debug with no breakpoints.

Then I get;

Then I step into ~7 times and then I get

This is essentially the same as before. The only difference is that if I put a breakpoint on the line after the eeprom_init the debugger never reaches the breakpoint (same error as before) when I have those lines commented out. With those lines the debugger does reach the breakpoint.

This is the debug circuit on the board I am using.

The datasheet does not have any pull-ups or a capacitor. Could this be the source of the debugging issue?

Thank you for help!

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

pavel_sadek — Fri, 16 Aug 2013 08:52:18 GMT

Hi again,

well, Reset is connected according ref manual fig. 2.5, that is correct. BKGD/MS pin pullup is not recomended anywhere however it has internal one, so the additional pullup hooked externally should not cause any issue.

I would point you to errata document, it is available on S08P product summary page, there are 2 for different masks of PA4, so choose the correct one.

there are few issues and their workarounds for Flash and Debugging mentioned

the raw code of yours works, this is proved by my last trial, so issue might be with missing workaround for your exact device (mask)

I do not have any PA4 device here to check.

Pavel

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Fri, 16 Aug 2013 14:36:42 GMT

Hello Pavel,

I looked at the errata here (This is an N36F mask)

http://cache.freescale.com/files/microcontrollers/doc/errata/S08PA4_0N36F.pdf?fpsp=1&WT_TYPE=Errata&WT_VENDOR=FREESCALE&…

I can't see where any of the issues are germane to what I am seeing? The flash issues (NVM) are related to the EEPROM?

Thank you again for your help!

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

pavel_sadek — Mon, 19 Aug 2013 08:28:34 GMT

yes - EEPROM is non volatile memory, there are 2 errata to check.

your code works correctly with PT.

why is reset tied to 4V instead of 5V?

Pavel

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Mon, 19 Aug 2013 16:55:33 GMT

Hello again Pavel,

What I mean is that, when you actually read the errata, all it talks about is protected "Flash". There is no indication that it affects EEPROM. Is EEPROM protected or partially protected? I never read anything, the second time I read it, that says that EEPROM is an issue.

I didn't see that 4V when I posted it. I can assure you that this board is not wired that way.

Thank you for your help.

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

pavel_sadek — Fri, 23 Aug 2013 09:34:14 GMT

Hi Gregory.

the EEEPROM has its protection too, it is stated on page 66 - 68 of reference manual, so it can be protected (or just partially protected - 32 / 64/ 96 or 128 bytes of size)

the workaround guides to use unprotected device

this errata / workaround does not apply to PT60, so you can test it on your PT60 twr board (same as I did successfully few days ago), that is why I feel this errata as a suspect.

Pavel

Re: Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

zbeehu — Wed, 28 Aug 2013 06:06:23 GMT

I also ran this code on myPA4TWR board -

then,I also close the watchdog

when I debug,it also show NO source available for"0x0000(0x0000)()"

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

pavel_sadek — Wed, 28 Aug 2013 09:39:40 GMT

Hi Gregory, Hu,

I have ordered PA4 sample to check your issue, I will be back soon with new reply

Pavel

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

gregoryberardi — Wed, 28 Aug 2013 14:15:20 GMT

Hello Pavel,

Thank you very much for the help!

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

pavel_sadek — Thu, 05 Sep 2013 08:45:43 GMT

Hi Gregory,

I have wired the sample with BDM and power source - looks ugly however works.

now I have loaded your latest code.

as I do not have anything hooked to the mcu, I had to replace your clock init whth

//hal_clk_init();

ICS_C3 = *(unsigned char*)0xFF6FU; //ICS trim

ICS_C2 &= (unsigned char)(~ ICS_C2_BDIV_MASK);

I have disabled the wdog, your code was missing the wdog unlock sequence which is not correct

WDOG_CNT = 0xC520; // write the 1st unlock word

WDOG_CNT = 0xD928; // write the 2nd unlock word

WDOG_CS1 = 0;

I am calling the eeprom functions from the main loop controled by global variable "operation" that I have made for this purpose.

hal_eeprom_write_4_bytes works ok on my side

hal_eeprom_erase_4_bytes is erasing only first sector (two bytes), you need to exclude the alignment control that you have placed there and erase in sequence both sectors that belongs to memory space (4 bytes) you want to erase - take a look into AN at page 6; segmantation is sector or whole block...

I have tested the debugger for freezing, I have noticed it occurs when fast toggling between run and stop, it might be due to propagation delays in eclipse (I have quite fast PC so it is not so obvious here for the first sight), however there were no freezes when stepping (F5/F6) at all.

I have also enabled the EEPROM preservation to exclude eeprom overwriting when debug session toggling (it is in propoerties of Multilink connection).

so as a conclusion - I think your issue was the watchdog, then you need to update the erase function and it might be ok

Pavel

Re: Writing EEPROM does not appear to be persistent when using example AN4570. MC9SO8PA4

zbeehu — Thu, 05 Sep 2013 08:56:02 GMT

It must close the watchdog?