Occasional problem with IAP EEPROM in LPC11U68

[pavelhudecek]

Hi,

i use these functions:

static uint32_t iapCmd[5], iapRes[4];

uint32_t iapEEread(uint16_t eAdr, uint8_t *data, uint16_t bytes) {

   iapCmd[0] = IAP_EEPROM_READ;

   iapCmd[1] = (uint32_t) eAdr;

   iapCmd[2] = (uint32_t) data;

   iapCmd[3] = (uint32_t) bytes;

   iapCmd[4] = SystemCoreClock / 1000;

   LED_d3=1;

   iap_entry(iapCmd, iapRes);

   LED_d3=0;

   return iapRes[0];

}

uint32_t iapEEwrite(uint16_t eAdr, uint8_t *data, uint16_t bytes) {

   iapCmd[0] = IAP_EEPROM_WRITE;

   iapCmd[1] = (uint32_t) eAdr;

   iapCmd[2] = (uint32_t) data;

   iapCmd[3] = (uint32_t) bytes;

   iapCmd[4] = SystemCoreClock / 1000;

   LED_d3=1;

   iap_entry(iapCmd, iapRes);

   LED_d3=0;

   return iapRes[0];

}

Usually it is working properly, but sometimes (approximately 10 % if hundreds bytes writed, for example 353 bytes, but not if tens bytes writed, and 2 incidents in reading) a problem occurred:

Program stops at address 0xfffffffe, and LED stay ON.

iap_entry is from romapi_11u6x.h

builded in LPCXpresso v8.1.4 [Build 606] [2016-03-14]

SystemCoreClock is from startup set to 48000000.LPC11U68JBD100 is on custom board, blocked with 100n+10n 0805 capacitors on every supply pins, and two 22uF caps near. Supplied from 3,0V LDO.

[pavelhudecek · Accepted solution]

How can i mark this discussion as solved?

[ursaminor]

I can't help with marking this topic as solved, but you probably want to try this out first anyway:

LPC1100/LPC1300 EEPROM Library | www.LPCware.com 

(The link is to the obsolete LPCware site, can't find it in the new forum...)

After all, you don't have to disable interrupts for EEPROM access.

[pavelhudecek]

Thank You, it is optimal solution.

[pavelhudecek]

I've found: The problem is caused by an interrupt.

Error not occurred afther these change:

LED_d3=1;

__disable_irq();

iap_entry(iapCmd, iapRes);

__enable_irq();

LED_d3=0;

But this solution I dislike. Functions are sometimes called upon already disabled interrupt and it is undesirable to be enabled in this case.

How can I detect whether the interrupt is enabled / disabled?

Thanks.

[avt]

int __disable_irq(void); returns the value the IRQ interrupt mask has in the PSR before disabling IRQ interrupts. 

So so check the return value to see if it was enabled or not...

[pavelhudecek]

Thank you, but this is not working. If I try to find declaration of __disable_irq, I see this:

__attribute__( ( always_inline ) ) __STATIC_INLINE void __disable_irq(void)

{

__ASM volatile ("cpsid i" : : : "memory");

}

[pavelhudecek]

Solution found:

__get_PRIMASK() returns 1/0 at depends on interrupt disabled/enabled.