M306V0ME Mitsubishi, M306V0ME Datasheet - Page 66

• Manufacturer Part Number: M306V0ME
• Description: SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER and ON-SCREEN DISPLAY CONTROLLER
• Manufacturer: Mitsubishi

66
Figure 2.7.14 Switching condition of INT interrupt request
(5) Rewrite interrupt control register
• To rewrite the interrupt control register, do so at a point that does not generate the interrupt request
• When a instruction to rewrite the interrupt control register is executed but the interrupt is disabled, the
for that register. If there is possibility of the interrupt request occur, rewrite the interrupt control regis-
ter after the interrupt is disabled. The program examples are described as follow:
interrupt request bit is not set sometimes even if the interrupt request for that register has been
generated. This will depend on the instruction. If this creates problems, use the below instructions to
change the register.
Instructions : AND, OR, BCLR, BSET
Example 1:
Example 2:
Example 3:
The reason why two NOP instructions (four when using the HOLD function) or dummy read are inserted
before FSET I in Examples 1 and 2 is to prevent the interrupt enable flag I from being set before the
interrupt control register is rewritten due to effects of the instruction queue.
INT_SWITCH1:
INT_SWITCH2:
INT_SWITCH3:
FCLR
AND.B
NOP
NOP
FSET
FCLR
AND.B
MOV.W MEM, R0
FSET
PUSHC FLG
FCLR
AND.B
POPC
I
#00h, 0055h ; Clear TA0IC int. priority level and int. request bit.
I
I
#00h, 0055h ; Clear TA0IC int. priority level and int. request bit.
I
I
#00h, 0055h ; Clear TA0IC int. priority level and int. request bit.
FLG
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER
; Disable interrupts.
; Four NOP instructions are required when using HOLD function.
; Enable interrupts.
; Disable interrupts.
; Dummy read.
; Enable interrupts.
; Push Flag register onto stack
; Disable interrupts.
; Enable interrupts.
(Enable the accepting of INTi interrupt request)
Set the interrupt priority level to level 1 to 7
______
Set the interrupt priority level to level 0
Clear the interrupt enable flag to “0”
Clear the interrupt request bit to “0”
Set the interrupt enable flag to “1”
Set the polarity select bit
(Disable
(Disable interrupt)
(Enable interrupt)
INTi
interrupt)
and ON-SCREEN DISPLAY CONTROLLER
MITSUBISHI MICROCOMPUTERS
M306V0ME-XXXFP
M306V0EEFP
Rev. 1.0