W741E260 Datasheet, PDF (23/94 Pages) Winbond – 4-BIT FLASH MICROCONTROLLER

W741E260
76543210
IEF w
w
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Note: W means write only.
IEF.0 = 1 Interrupt 0 is accepted by overflow from the Divider 0.
IEF.1 = 1 Interrupt 1 is accepted by underflow from the Timer 0.
IEF.2 = 1 Interrupt 2 is accepted by a signal change at port RC.
IEF.3 is reserved.
IEF.4 = 1 Interrupt 4 is accepted by overflow from the Divider 1 for W741C260 body.
Interrupt 4 is accepted by a falling edge signal at the INT pin for W741C250 body.
IEF.5 & IEF.6 are reserved.
IEF.7 = 1 Interrupt 7 is accepted by underflow from Timer 1.
Stop Mode Operation
In stop mode, all operations of the µC cease (excluding the operation of the sub-oscillator and divider 1
when the dual-clock operation mode is selected). The µC enters stop mode when the STOP instruction
is executed and exits stop mode when an external trigger is activated (by a falling signal on the RC
port for W741C260 body or by a falling signal on the RC port or a low level on the INT pin for
W741C250 body). When the designated signal is accepted, the µC awakens and executes the next
instruction (if the corresponding bits of IEF and PEF have been set, It will enter the interrupt service
routine after stop mode released). To prevent erroneous execution, the NOP instruction should follow
the STOP command. But In the dual-clock slow operation mode, the STOP instruction will disable the
main-oscillator oscillating; the µC system is still operated by the sub-oscillator.
Stop Mode Wake-up Enable Flag for RC Port (SEF)
The stop mode wake-up flag for port RC is organized as an 4-bit binary register (SEF.0 to SEF.3).
Before port RC may be used to make the device exit the stop mode, the content of the SEF must be
set first. The SEF is controlled by the MOV SEF, #I instruction. The bit descriptions are as follows:
3
2
1
0
SEF w w w w
Note: W means write only.
SEF.0 = 1
SEF.1 = 1
SEF.2 = 1
SEF.3 = 1
Device will exit stop mode when falling edge signal is applied to pin RC.0
Device will exit stop mode when falling edge signal is applied to pin RC.1
Device will exit stop mode when falling edge signal is applied to pin RC.2
Device will exit stop mode when falling edge signal is applied to pin RC.3
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Publication Release Date: March 1998
Revision A2