Advertisement
Pe nt e k Mo del 4284 Oper ating Manual
4.3
Flash EEPROM Operations
4.3.3
Erasing the Flash EEPROM
4.3.3.2
4.3.4
Moving the Code from Global DRAM to Flash EEPROM
After the Flash EEPROM sectors you wish to move your code into have been
erased, you are ready to copy your code from the DRAM to the Flash
EEPROM. This will also involve the use of some of the firmware functions
described in
at the top of the next page.
Artisan Technology Group - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisantg.com
(continued)
(continued)
Erasing Selected Flash EEPROM Sectors
Individual sectors of the Flash memory can be erased by calling
some of the functions described in
manual. The procedure is described below:
1) Read the pointer to the Flash Erase Sector function from
DRAM_base+0x0854. Write the result of that read into
the Host Function Command Pointer location,
DRAM_base+0x0000 0800.
2) Write the address of the sector to be erased (from
Table
4−5, previous page) to the Flash Boot Address location,
DRAM_base+0x0000 0804.
3) Write a '0' to the Host Read y Flag L ocation,
DRAM_ base+0x000 0 081 0.
4) Set the Host Interrupt Bit in the 4284's Host Control Register to
the '1' state, by writing a '2' to A16_base+0x0004.
5) The firmware will now begin to erase the Flash EEPROM
sector at the address given in step (2), on the previous page.
6) Poll the Host Ready Flag (DRAM_base+0x0000 0810). This will
be set to the '1' state by the firmware upon completion of the
sector erase operation.
If necessary, the procedure described above can be repeated to
erase additional sectors. Note that the entire Flash EEPROM can
also be erased using the procedure above, if you begin by copying
the Flash Erase function pointer (at DRAM_base+0x0000 0850) to
the Host Command location, instead of the Flash Erase Sector
pointer.
Table 4−2
(see
page
59). A description of the procedure begins
P age 67
(continued)
Table
4−2, on
page 59
of this
Rev.: F.2
Advertisement
