ST52F513G3M6 STMicroelectronics, ST52F513G3M6 Datasheet - Page 42

• Manufacturer Part Number: ST52F513G3M6
• Manufacturer: STMicroelectronics

Specifications of ST52F513G3M6

• Cpu Family: ST52
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: I2C/SCI/SPI
• Program Memory Type: Flash
• Program Memory Size: 8KB
• Total Internal Ram Size: 256Byte
• # I/os (max): 22
• Number Of Timers - General Purpose: 2
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5V
• Operating Supply Voltage (min): 2.7V
• On-chip Adc: 8-chx10-bit
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 28
• Package Type: SO
• Lead Free Status / Rohs Status: Compliant

ST52510xx ST52513xx
5 INTERRUPTS
The Control Unit (CU) responds to peripheral
events and external events through its interrupt
channels.
When such events occur, if the related interrupt is
not masked and doesn’t have a priority order, the
current program execution can be suspended to
allow the CU to execute a specific response
routine.
Each interrupt is associated with an interrupt
vector that contains the memory address of the
related interrupt service routine. Each vector is
located in the Program/Data Memory space at a
fixed address (see
Memory
5.1 Interrupt Processing
If interrupts are pending at the end of an arithmetic
or logic instruction, the interrupt with the highest
priority is acknowledged. When the interrupt is
acknowledged the flags and the current PC are
saved in the stacks and the associated Interrupt
routine is executed. The start address of this
routine (Interrupt Vector) is located in two bytes of
the Program/Data Memory, plus another byte for
the JUMP or RETI opcode, between address 3 and
32 (03h-020h). See
Interrupt Vector addresses.
The Interrupt routine is performed as a normal
code. At the end of any instruction, the CU checks
if a higher priority interrupt has sent an interrupt
request. An Interrupt request with a higher priority
stops lower priority Interrupts. The Program
Counter and the flags are stored in their own
stacks.
With the instruction RETI (Return from Interrupt)
the flags and the Program Counter (PC) are
restored from the top of the stacks. These stacks
have already been described in
An Interrupt request cannot stop fuzzy rule
processing. The request is acknowledged only
after the end of a fuzzy rule or at the end of a logic
or arithmetic instruction, unless a Global Interrupt
Disable instruction has been executed before.
Remark: A fuzzy routine can be interrupted only in
the Main program. When a Fuzzy function is
running inside another interrupt routine an interrupt
request can cause side effects in the Control Unit.
For this reason, in order to use a Fuzzy function
inside an interrupt routine, the user MUST include
the Fuzzy function between an UDGI (MDGI)
instruction and an UEGI (MEGI) instruction (see
the following paragraphs), in order to disable the
interrupt request during the execution of the fuzzy
function.
42/136
Organization).
Table 5.1
Figure 3.2 Program/Data
Paragraph
for the list of the
3.4.
Figure 5.1
5.2 Global Interrupt Request Enabling
When an Interrupt occurs, it generates a Global
Interrupt Pending (GIP). After a GIP a Global
Interrupt Request (GIR) will be generated and
Interrupt Service Routine associated with the
interrupt with higher priority will start.
In order to avoid possible conflicts between the
interrupt masking set in the main program, or
inside high level language compiler macros, the
GIP is put in AND through the User Global Interrupt
Mask or the Macro Global Interrupt Mask (see
Figure
The UEGI/UDGI instruction switches the User
Global Interrupt Mask enabling/disabling the GIR
for the main program.
MEGI/MDGI instructions switch the Macro Global
Interrupt Mask on/off in order to ensure that the
macro will not be interrupted.
Figure 5.2 Global Interrupt Request
Global Interrupt
Pending
User Global
Interrupt Mask
Macro Global
INTERRUPT
5.2).
Interrupt Flow
PROGRAM
NORMAL
FLOW
Global Interrupt
Request
INSTRUCTION
INTERRUPT
ROUTINE
SERVICE
RETI