ST72260G, ST72262G, ST72264G
15 DEVICE CONFIGURATION AND ORDERING INFORMATION
Each device is available for production in user pro-
grammable versions (FLASH) as well as in factory
coded versions (ROM/FASTROM).
ST7226x devices are ROM versions. ST72P26x
devices are Factory Advanced Service Technique
ROM (FASTROM) versions: they are factory-pro-
grammed XFlash devices.
ST72F26x XFlash devices are shipped to custom-
ers with a default program memory content (FFh).
The option bytes are programmed to enable the in-
ternal RC oscillator. The ROM/FASTROM factory
coded parts contain the code supplied by the cus-
tomer. This implies that FLASH devices have to be
configured by the customer using the Option Bytes
while the ROM/FASTROM devices are factory-
configured.
15.1 OPTION BYTES
The two option bytes allow the hardware configu-
ration of the microcontroller to be selected.
The option bytes have no address in the memory
map and can be accessed only in programming
mode (for example using a standard ST7 program-
ming tool). The default content of the FLASH is
fixed to FFh.
In masked ROM devices, the option bytes are
fixed in hardware by the ROM code (see option
list).
USER OPTION BYTE 0
OPT 7 = WDG HALT Watchdog reset on HALT
This option bit determines if a RESET is generated
when entering HALT mode while the Watchdog is
active.
0: No Reset generation when entering Halt mode
1: Reset generation when entering Halt mode
0: Hardware (watchdog always enabled)
1: Software (watchdog to be enabled by software)
OPT 5:4 = VD[1:0] Voltage detection selection
These option bits enable the voltage detection
block (LVD and AVD) with a selected threshold ot
the LVD and AVD.
Configuration
VD1 VD0
LVD Off
Lowest Voltage Threshold (∼3.05V)
11
10
Medium Voltage Threshold (∼3.6V)
01
Highest Voltage Threshold (∼4.1V)
00
OPT 3:2 = SEC[1:0] Sector 0 size definition
These option bits indicate the size of sector 0 ac-
cording to the following table.
Sector 0 Size
SEC1
SEC0
0.5k
0
0
1k
0
1
2
1
0
4k
1
1
OPT 1 = FMP_R Read-out protection
This option indicates if the program memory is pro-
tected against piracy See “Memory Protection” on
page 16.. The read-out protection blocks access
to the program memory in any mode except user
mode and IAP mode. Erasing the option bytes
when the FMP_R option is selected will cause the
whole memory to be erased first, and the device
can be reprogrammed. Refer to Section 4.5 and
the ST7 Flash Programming Reference Manual for
more details.
0: Read-out protection off
1: Read-out protection on
OPT 6 = WDG SW Hardware or software watch-
dog
This option bit selects the watchdog type.
USER OPTION BYTE 0
USER OPTION BYTE 1
7
07
0
OSC OSC OSC OSC OSC
WDG WDG
HALT SW
VD1
VD0
SEC
1
SEC
0
FMP
R
FMP
W
EXTIT
PLL
CSS TYPE TYPE RNGE RNGE RNGE
OFF
10
2
1
0
Default
Value
1
1
1
1
1
1
0
0
1
110
1
1
1
1
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