PFS172 datasheet(88/92 Pages) PADAUK

88 / 92 page

PFS172

8bit MTP MCU with 8-bit ADC

Page 88 of 92

PDK-DS-PFS172-EN_V000-May 8, 2020

Technology is not responsible for this: the quality of the user's crystal oscillator is not good, the usage

conditions are unreasonable, the PCB cleaner leakage current, or the PCB layouts are unreasonable.

9.2.2. Interrupt

(1) When using the interrupt function, the procedure should be:

Step1: Set INTEN register, enable the interrupt control bit

Step2: Clear INTRQ register

Step3: In the main program, using ENGINT to enable CPU interrupt function

Step4: Wait for interrupt. When interrupt occurs, enter to Interrupt Service Routine

Step5: After the Interrupt Service Routine being executed, return to the main program

* Use DISGINT in the main program to disable all interrupts

* When interrupt service routine starts, use PUSHAF instruction to save ALU and FLAG

void Interrupt (void)

// Once the interrupt occurs, jump to interrupt service routine

{

// enter DISGINT status automatically, no more interrupt is

accepted

PUSHAF;

…

POPAF;

}

// RETI will be added automatically. After RETI being executed, ENGINT status

will be restored

(2) INTEN and INTRQ have no initial values. Please set required value before enabling interrupt function.

(3) There are two sets of external IO pin interrupt source. Every set is decided by code option Interrupt Src0

and Interrupt Src1 corresponding to the unique interrupt pin. Please comply with the inten / intrq / integs

9.2.3. System clock switching

System clock can be switched by CLKMD register. Please notice that, NEVER switch the system clock and

turn off the original clock source at the same time. For example: When switching from clock A to clock B,

please switch to clock B first; and after that turn off the clock A oscillator through CLKMD.



Example : Switch system clock from ILRC to IHRC/2

CLKMD

0x36;

// switch to IHRC, ILRC can not be disabled here

CLKMD.2 =

// ILRC can be disabled at this time



ERROR: Switch ILRC to IHRC and turn off ILRC simultaneously

CLKMD

0x50;

// MCU will hang

9.2.4. Watchdog

Watchdog will be inactive once ILRC is disabled.

PFS172 Datasheet(PDF) 88 Page - PADAUK Technology.

PFS172 Datasheet(HTML) 88 Page - PADAUK Technology.

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92

Datasheet Download

Link URL