ST72321B STMICROELECTRONICS [STMicroelectronics], ST72321B Datasheet - Page 175

• Manufacturer Part Number: ST72321B
• Description: 64/44-pin 8-bit MCU with 32 to 60K Flash/ROM, ADC, five timers, SPI, SCI, I2C interface
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

ST72321B DEVICE CONFIGURATION AND ORDERING INFORMATION (Cont’d)
OPT0= FMP_R Flash memory read-out protection
Read-out protection, when selected, provides a
protection against Program Memory content ex-
traction and against write access to Flash memo-
ry.
Erasing the option bytes when the FMP_R option
is selected causes the whole user memory to be
erased first, and the device can be reprogrammed.
Refer to
gramming Reference Manual for more details.
0: Read-out protection enabled
1: Read-out protection disabled
OPTION BYTE 1
OPT7= PKG1 Package selection bit 1
This option bit selects the package.
Note: On the chip, each I/O port has up to 8 pads.
Pads that are not bonded to external pins are
forced in input pull-up configuration after reset.
The configuration of these pads must be kept at
reset state to avoid added current consumption.
are in input floating configuration after reset. Refer
to Note 4 on
OPT6 = RSTC RESET clock cycle selection
This option bit selects the number of CPU cycles
applied during the RESET phase and when exiting
HALT mode. For resonator oscillators, it is advised
to select 4096 due to the long crystal stabilization
time.
0: Reset phase with 4096 CPU cycles
1: Reset phase with 256 CPU cycles
OPT5:4 = OSCTYPE[1:0] Oscillator Type
These option bits select the ST7 main clock
source type.
Resonator Oscillator
Reserved
Internal RC Oscillator
Version
R/AR
K
J
Clock Source
Section 4.3.1
Selected Package
page
LQFP64
LQFP44
LQFP32
13.
and the ST7 Flash Pro-
Flash size
32/48/60K
48/60K
1
0
0
1
32K
32K
OSCTYPE
PKG 1
0
0
1
0
1
0
1
0
OPT3:1 = OSCRANGE[2:0] Oscillator range
When the resonator oscillator type is selected,
these option bits select the resonator oscillator
current source corresponding to the frequency
range of the used resonator. Otherwise, these bits
are used to select the normal operating frequency
range.
OPT0 = PLLOFF PLL activation
This option bit activates the PLL which allows mul-
tiplication by two of the main input clock frequency.
The PLL is guaranteed only with an input frequen-
cy between 2 and 4MHz, for this reason the PLL
must not be used with the internal RC oscillator.
0: PLL x2 enabled
1: PLL x2 disabled
CAUTION: the PLL can be enabled only if the
“OSC RANGE” (OPT3:1) bits are configured to “
2~4MHz”. Otherwise, the device functionality is
not guaranteed.
External Source
Typ. Freq. Range
Clock Source
8~16MHz
1~2MHz
2~4MHz
4~8MHz
2
0
0
0
0
OSCRANGE
1
1
OSCTYPE
1
0
0
1
1
175/187
0
1
0
0
1
0
1