ST92F124XX Datasheet, PDF (80/523 Pages) STMicroelectronics – In-Application Programming

Single voltage Flash and E3™ (emulated EEPROM)
7.3
7.3.1
Register description
Control registers
FLASH CONTROL REGISTER (FCR)
Address: 224000h / 221000h- Read/Write
Reset value: 0000 0000 (00h)
7
6
5
FWMS FPAGE FCHIP
4
FBYTE
3
FSECT
2
FSUSP
1
PROT
0
FBUSY
The Flash Control Register is used to enable all the operations for the Flash and the
TestFlash memories.
Bit 7 = FWMS: Flash Write Mode Start (Read/Write).
This bit must be set to start each write/erase operation in Flash memory. At the end of the
write/erase operation or during a Sector Erase Suspend this bit is automatically reset. To
resume a suspended Sector Erase operation, this bit must be set again. Resetting this bit by
software does not stop the current write operation.
0: No effect
1: Start Flash write
Bit 6 = FPAGE: Flash Page program (Read/Write).
This bit must be set to select the Page Program operation in Flash memory. This bit is
automatically reset at the end of the Page Program operation.
The Page Program operation allows to program “0”s in place of “1”s. From 1 to 16 bytes can
be entered (in any order, no need for an ordered address sequence) before starting the
execution by setting the FWMS bit. All the addresses must belong to the same page (only
the 4 LSBs of address can change). Data to be programmed and addresses in which to
program must be provided (through an LD instruction, for example). Data contained in page
addresses that are not entered are left unchanged.
0: Deselect page program
1: Select page program
Bit 5 = FCHIP: Flash CHIP erase (Read/Write). This bit must be set to select the Chip Erase
operation in Flash memory. This bit is automatically reset at the end of the Chip Erase
operation.
The Chip Erase operation erases all the Flash locations to FFh. The operation is limited to
Flash code: sectors F0-F3 (or F0-F5 for the ST92F250), TestFlash and E^{3 TM} excluded. The
execution starts by setting the FWMS bit. It is not necessary to pre-program the sectors to
00h, because this is done automatically.
0: Deselect chip erase
1: Select chip erase
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Doc ID 8848 Rev 7