TC1796
Peripheral Units (Vol. 2 of 2)
Micro Link Interface (MLI)
User’s Manual
23-55
V2.0, 2007-07
MLI, V2.0
23.2.4
MLI Service Request Generation
The MLI module’s service request outputs SRx are used to indicate module internal MLI
events to other modules or devices outside the MLI module, depending on the device
implementation. They can trigger interrupts of a CPU (if available), can be used as DMA
request lines (if available), or for other trigger purposes. The MLI events being able to
trigger interrupts or other service requests, names of some flags and control registers
refer to interrupt generation.
MLI module events are generated by event sources in the transmitter and in the receiver.
Each event source provides a status flag and an enable bit with software clear capability.
In some cases, several event sources are combined to a common event. An MLI event,
internally generated by an event source as a request pulse, is stored in a status flag that
is located in the interrupt status registers TISR (for transmitter events) or RISR (for
receiver events). All event flags can be cleared individually by software write actions to
bits located in the interrupt enable registers TIER (for transmitter events) or RIER (for
receiver events). These two registers also contain the enable control bits that allow each
event source to be enabled/disabled individually for service request activation. Each
event can be connected to exactly one of the eight service request outputs SR[7:0] by a
3-bit interrupt node pointer.
One additional register, the Global Interrupt Set Register GINTR, allows each service
request output to be activated separately without setting the status flags of the event
sources (see
). This feature is sometimes helpful for software test purposes
or to trigger MLI external actions.
Interrupt Registers
The MLI event sources are controlled by several registers (for transmitter see
, for receiver see
). The register name prefixes “T” and “R”
indicate if a register is assigned to the MLI transmitter or to the MLI receiver.
Service Request Compressor
The MLI event logic uses a compressing scheme for flexible service request processing.
Eleven MLI events (six transmitter events and four of the five receiver events) are
directed via a 3-bit interrupt node pointer to one of the eight service request outputs
Table 23-6
Interrupt Registers
Unit
Registers with
Request Flags
Enable Bits/
Req. Flag Clear Bits
Node Pointer
MLI Transmitter TISR
TIER
TINPR
MLI Receiver
RISR
RIER
RINPR