User Manual
337
Rev. 1.1
2019-03-18
TLE984xQX
Microcontroller with LIN and Power Switches for Automotive Applications
Interrupt System
13.4
Interrupt Structure
An interrupt event source may be generated from the on-chip peripherals or from external. Detection of
interrupt events is controlled by the respective on-chip peripherals. Interrupt status flags are available for
determining which interrupt event has occurred, especially useful for an interrupt node which is shared by
several event sources. Each interrupt node (except NMI) has a global enable/disable bit. In most cases,
additional enable bits are provided for enabling/disabling particular interrupt events (provided for NMI
events). No interrupt will be requested for any occurred event that has its interrupt enable bit disabled.
The interrupt masking bit, EA, is used to globally enable or disable all interrupt requests (except NMI) to the
core. Resetting bit EA to 0 only masks the pending interrupt requests from the core, but does not block the
capture of incoming interrupt requests.
13.4.1
Interrupt Structure 1
For interrupt structure 1 (see
), the interrupt event will set the interrupt status flag which doubles as
a pending interrupt request to the core. An active pending interrupt request will interrupt the core only if it is
corresponding interrupt node is enabled. Once an interrupt node is serviced (interrupt acknowledged), its
pending interrupt request (represented by the interrupt status flag) may be automatically cleared by
hardware (the core).
Figure 71 Interrupt Structure 1
For the TLE984xQX, interrupt sources like ADC10 and MU(each have a dedicated interrupt node) will have their
respective interrupt status flags in the dedicated registers. This flags are not cleared by the core once their
corresponding pending interrupt request is serviced. They have to cleared by software. For the UART which
has its dedicated interrupt node, interrupt status flags RI and TI in register SCON will not be cleared by the core
even when its pending interrupt request is serviced. The UART interrupt status flags (and hence the pending
interrupt request) can only be cleared by software.
For interrupts related to edge-detection the behaviour is slightly different, when interrupts are disabled and
re-enabled. This behaviour occurs at MON (node 22) and EXTINT (node 12, 13, shared node 11). The event
(detected edge) is stored in register bits (in IRCON0 or IRCON1) as for other interrupts as well. But the
signalling to the core is done directly from the event, not from the register bit (see also the figures in
). While the interrupt is disabled (e.g. via EA-bit), incoming edges are stored in the register bits,
and not signalled to the core. When re-enabling the interrupt, the missed event is visible in the bit, but no re-
signalled to the core.
set
pending
interrupt
request
interrupt node
enable bit
interrupt status
flag
interrupt
event
software
clear
clear
interrupt
acknowledge
(from core)
AND
EA bit
to core