ST7LITE1xB
15 DEVICE CONFIGURATION AND ORDERING INFORMATION
Each device is available for production in user pro-
grammable versions (FLASH).
ST7FLITE1xB devices are shipped to customers
with a default program memory content (FFh).
This implies that FLASH devices have to be con-
figured by the customer using the Option Bytes.
15.1 OPTION BYTES
The two option bytes allow the hardware configu-
ration of the microcontroller to be selected.
The option bytes can be accessed only in pro-
gramming mode (for example using a standard
ST7 programming tool).
OPT3:2 = 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
OPTION BYTE 0
OPT7 = Reserved, must always be 1.
1k
0
1
2k
1
0
4k
1
1
OPT6 = PKG Package selection
0: 16-pin package
1: 20-pin package
OPT5:4 = CLKSEL Clock Source Selection
When the internal RC oscillator is not selected
(Option OSC=1), these option bits select the clock
source: resonator oscillator or external clock
Clock Source
Port C
CLKSEL
Resonator
Ext. Osc Disabled/
Port C Enabled
0
0
Ext.
on PB4 Ext. Osc Enabled/ 0 1
Clock source:
Port C Disabled
CLKIN
on PC0
11
Reserved
10
Note: When the internal RC oscillator is selected,
the CLKSEL option bits must be kept at their de-
fault value in order to select the 256 clock cycle
delay (see Section 7.5).
OPT1 = FMP_R Read-out protection
Readout protection, when selected provides a pro-
tection against program memory content extrac-
tion and against write access to Flash memory.
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 the ST7 Flash Programming Reference
Manual and section 4.5 on page 14 for more de-
tails
0: Read-out protection off
1: Read-out protection on
OPT0 = FMP_W FLASH write protection
This option indicates if the FLASH program mem-
ory is write protected.
Warning: When this option is selected, the pro-
gram memory (and the option bit itself) can never
be erased or programmed again.
0: Write protection off
1: Write protection on
7
Res. PKG
Default
Value
1
1
OPTION BYTE 0
OPTION BYTE 1
07
0
CLKSEL
SEC1 SEC0
FMP
R
FMP
W
PLL
x4x8
PLL
OFF
PLL32
OFF
OSC
LVD1
LVD0
WDG WDG
SW HALT
110 100 1 1
1
01111
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