ST72C334N2B6 STMicroelectronics, ST72C334N2B6 Datasheet - Page 48

• Manufacturer Part Number: ST72C334N2B6
• Description: Microcontrollers (MCU) Flash 8K SPI/SCI
• Manufacturer: STMicroelectronics

Specifications of ST72C334N2B6

• Data Bus Width: 8 bit
• Program Memory Type: Flash
• Program Memory Size: 8 KB
• Data Ram Size: 384 B
• Interface Type: SCI, SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 44
• Number Of Timers: 16 bit
• Operating Supply Voltage: 3.2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• Package / Case: SDIP-56
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit
• Lead Free Status / Rohs Status: No

ST72334J/N, ST72314J/N, ST72124J
MISCELLANEOUS REGISTERS (Cont’d)
6.2.3 Miscellaneous Registers Description
MISCELLANEOUS REGISTER 1 (MISCR1)
Read/Write
Reset Value: 0000 0000 (00h)
Bit 7:6 = IS1[1:0] EI2 and EI3 sensitivity
The interrupt sensitivity, defined using the IS1[1:0]
bits, is applied to the following external interrupts:
EI2 (port B3..0) and EI3 (port B7..4). These 2 bits
can be written only when the I bit of the CC register
is set to 1 (interrupt disabled).
Bit 5 = MCO Main clock out selection
This bit enables the MCO alternate function on the
I/O port. It is set and cleared by software.
0: MCO alternate function disabled
1: MCO alternate function enabled
Note: To reduce power consumption, the MCO
function is not active in ACTIVE-HALT mode.
48/125
IS11 IS10
IS11
0
0
1
1
(I/O pin free for general-purpose I/O)
(f
7
OSC
IS10 MCO IS21
/2 on I/O port)
0
1
0
1
Falling edge & low level
Rising edge only
Falling edge only
Rising and falling edge
External Interrupt Sensitivity
IS20
CP1
CP0
SMS
0
Bit 4:3 = IS2[1:0] EI0 and EI1 sensitivity
The interrupt sensitivity, defined using the IS2[1:0]
bits, is applied to the following external interrupts:-
EI0 (port A3..0) and EI1 (port F2..0). These 2 bits
can be written only when the I bit of the CC register
is set to 1 (interrupt disabled).
Bit 2:1 = CP[1:0] CPU clock prescaler
These bits select the CPU clock prescaler which is
applied in the different slow modes. Their action is
conditioned by the setting of the SMS bit. These
two bits are set and cleared by software
Bit 0 = SMS Slow mode select
This bit is set and cleared by software.
0: Normal mode. f
1: Slow mode. f
See low power consumption mode and MCC
chapters for more details.
CP1 CP0
0
1
0
1
0
0
1
1
f
f
f
f
OSC
OSC
OSC
OSC
CPU
/ 4
/ 8
/ 16
/ 32
CPU
is given by CP1, CP0
f
CPU
=
f
OSC
in SLOW mode
/ 2