Maxim Integrated MAXQ Family Users Guide: MAXQ2000 Supplement - Manual (Page 87)

UTILITY ROM (SPECIFIC TO MAXQ2000)
The MAXQ2000 utility ROM includes routines that provide the following functions to application software.
• In-application programming routines for flash memory (program, erase, mass erase)
• Single word/byte copy and buffer copy routines for use with lookup tables
To provide backward compatibility among different versions of the utility ROM, a function address table is included that contains the
entry points for all user-callable functions. With this table, user code can determine the entry point for a given function as follows.
1) Read the location of the function address table from address 0800Dh in the Utility ROM.
2) The entry points for each function listed below are contained in the function address table, one word per function, in the order given
by their function numbers.
For example, the entry point for the flashEraseAll function can be determined by the following procedure.
1) functionTable = dataMemory[0800Dh]
2) flashWriteEntry = dataMemory[functionTable + 2]
Table 48. Utility ROM User Functions (for Utility ROM Version 1.01)
It is also possible to call utility ROM functions directly, using the entry points given in Table 48. Standard include files are provided for
this purpose with the MAXQ development tool set. This method calls functions more quickly, but the application may need to be recom-
piled in order to run properly with a different version of the utility ROM.
In-Application Programming Functions
Function: flashWrite
Summary: Programs a single word of flash memory.
Inputs: A[0]:Word address in program flash memory to write to.
A[1]: Word value to write to flash memory.
Outputs: Carry: Set on error and cleared on success.
Destroys: PSF, LC[1]
Notes:
1) If the watchdog reset function is active, it should be disabled before calling this function.
2) If the flash location has already been programmed to a non-FFFF value, this function returns with an error (Carry set). To reprogram
a flash location, it must first be erased by calling flashErasePage or flashEraseAll.
MAXQ Family User’s Guide:
MAXQ2000 Supplement
FUNCTION NUMBER FUNCTION NAME ENTRY POINT SUMMARY
0 flashWrite 08461h Programs a single word of flash memory.
1 flashErasePage 08467h Erases (programs to FFFFh) a 256-word sector of flash memory.
2 flashEraseAll 08478h Erases (programs to FFFFh) all flash memory.
3 moveDP0 08487h Reads a byte/word at DP[0].
4 moveDP0inc 0848Ah Reads a byte/word at DP[0], then increments DP[0].
5 moveDP0dec 0848Dh Reads a byte/word at DP[0], then decrements DP[0].
6 moveDP1 08490h Reads a byte/word at DP[1].
7 moveDP1inc 08493h Reads a byte/word at DP[1], then increments DP[0].
8 moveDP1dec 08496h Reads a byte/word at DP[1], then decrements DP[0].
9 moveFP 08499h Reads a byte/word at BP[Offs].
10 moveFPinc 0849Ch Reads a byte/word at BP[Offs], then increments Offs.
11 moveFPdec 0849Fh Reads a byte/word at BP[Offs], then decrements Offs.
12 copyBuffer 084A2h Copies LC[0] values from DP[0] to BP[Offs].
Maxim Integrated 87