User guide

DS4830A User’s Guide
232
25.2 – In-Application Programming Functions
25.2.1 – UROM_flashWrite
Function UROM_flashWrite
Summary Programs a single word of flash memory
Inputs
A[0]: Word address in program flash memory to write.
A[1]: Value to write to flash memory.
Outputs Carry: Set on error and cleared on success
Destroys PSF, LC[1]
Notes:
• This function uses two stack levels to save and restore values.
• If the watchdog reset function is active, it should be disabled before calling this function.
• Interrupts are disabled while in this function.
• If the flash location has already been programmed to a value other than FFFFh, this function returns with an
error (Carry set). In order to reprogram a flash location, the location must first be erased by calling
UROM_flashErasePage or UROM_flashEraseAll.
25.2.2 – UROM_flashErasePage
Function UROM_flashErasePage
Summary Erases (programs to FFFFh ) a 512-byte page of flash memory.
Inputs
A[0]: Word address located in the page to be erased. (The page number is the high 8 bits of
A[0].)
Outputs Carry: Set on error and cleared on success.
Destroys
PSF, LC[1], GR, AP, APC, A[0]
Notes:
• If the watchdog reset function is active, it should be disabled before calling this function.
• Interrupts are disabled while in this function.
• When calling this function from flash, care should be taken that the return address is not in the page which is
being erased.
25.2.3 –
UROM_flashEraseAll
Function UROM_flashEraseAll
Summary Erases (programs to FFFFh ) all locations in flash memory
Inputs
None
Outputs Carry: Set on error and cleared on success.
Destroys PSF, GR, LC[1], LC[0], AP, APC, A[0]
Notes:
• If the watchdog reset function is active, it should be disabled before calling this function.
• Interrupts are disabled while in this function..
• This function can only be called by code running from the RAM. Attempting to call this function while running
from the flash results in an error.