ST62T00CB6 STMicroelectronics, ST62T00CB6 Datasheet - Page 27

• Manufacturer Part Number: ST62T00CB6
• Description: IC MCU 8BIT OTP 1K 16-PDIP
• Manufacturer: STMicroelectronics
• Series: ST6r

Specifications of ST62T00CB6

• Core Processor: ST6
• Core Size: 8-Bit
• Speed: 8MHz
• Peripherals: LVD, POR, WDT
• Number Of I /o: 9
• Program Memory Size: 1KB (1K x 8)
• Program Memory Type: OTP
• Ram Size: 64 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 6 V
• Data Converters: A/D 4x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 16-DIP (0.300", 7.62mm)
• Controller Family/series: ST6
• No. Of I/o's: 9
• Ram Memory Size: 64Byte
• Cpu Speed: 8MHz
• No. Of Timers: 1
• Rohs Compliant: Yes
• Processor Series: ST62T0x
• Core: ST6
• Data Bus Width: 8 bit
• Data Ram Size: 64 B
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 9
• Number Of Timers: 2
• Operating Supply Voltage: 3 V to 6 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• Development Tools By Supplier: ST622XC-KIT/110, ST62GP-EMU2, ST62E2XC-EPB/110, ST62E6XC-EPB/US, STREALIZER-II
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit
• Cpu Family: ST6
• Device Core Size: 8b
• Frequency (max): 8MHz
• Total Internal Ram Size: 64Byte
• # I/os (max): 9
• Number Of Timers - General Purpose: 1
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 6V
• Operating Supply Voltage (min): 3V
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Through Hole
• Pin Count: 16
• Package Type: PDIP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Connectivity: -
• Lead Free Status / Rohs Status: In Transition
• Other names: 497-2093-5

INTERRUPTS (Cont’d)
3.4.2 Interrupt Procedure
The interrupt procedure is very similar to a call pro-
cedure, indeed the user can consider the interrupt
as an asynchronous call procedure. As this is an
asynchronous event, the user cannot know the
context and the time at which it occurred. As a re-
sult, the user should save all Data space registers
which may be used within the interrupt routines.
There are separate sets of processor flags for nor-
mal, interrupt and non-maskable interrupt modes,
which are automatically switched and so do not
need to be saved.
The following list summarizes the interrupt proce-
dure:
MCU
– The interrupt is detected.
– The C and Z flags are replaced by the interrupt
– The PC contents are stored in the first level of
– The normal interrupt lines are inhibited (NMI still
– The first internal latch is cleared.
– Theassociated interrupt vectoris loaded inthe PC.
WARNING: In some circumstances, when a
maskable interrupt occurs while the ST6 core is in
NORMAL mode and especially during the execu-
tion of an ”ldi IOR, 00h” instruction (disabling all
maskable interrupts): if the interrupt arrives during
the first 3 cycles of the ”ldi” instruction (which is a
4-cycle instruction) the core will switch to interrupt
mode BUT the flags CN and ZN will NOT switch to
the interrupt pair CI and ZI.
User
– User selected registers are saved within the in-
– The source of the interrupt is found by polling the
– The interrupt is serviced.
– Return from interrupt (RETI)
flags (or by the NMI flags).
the stack.
active).
terrupt service routine (normally on a software
stack).
interrupt flags (if more than one source is associ-
ated with the same vector).
MCU
– Automatically the MCU switches back to the nor-
The interrupt routine usually begins by the identify-
ing the device which generated the interrupt re-
quest (by polling). The user should save the regis-
ters which are used within the interrupt routine in a
software stack. After the RETI instruction is exe-
cuted, the MCU returns to the main routine.
Figure 20. Interrupt Processing Flow Chart
mal flag set (or the interrupt flag set) and pops
the previous PC value from the stack.
YES
NO
PROGRAM FLAGS
THE INS TRU CTION
INT ERR UP T MASK
THE STACK ED PC
IN STRUC TION
INS TRU CTION
INS TRU CTION
EXEC UTE
A RE TI
ST62T00C/T01C ST62T03C/E01C
SELECT
WAS
FETCH
C LEAR
”POP”
?
?
YES
N O
YES
?
NORMAL MODE?
AN IN TER RUP T R EQUEST
NO
AN D INTE RRU PT MASK
IS THE CORE
ALREADY IN
C HEC K IF THER E IS
IN TERNA L MODE FLAG
PC IN TO THE STACK
INT ERR UP T VEC TOR
INTER RU PT MASK
LOAD PC FROM
PUSH THE
(FFC/FFD)
SELECT
SET
VA000014
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