SDA6000 Datasheet, PDF (167/380 Pages) Infineon Technologies AG – Teletext Decoder with Embedded 16-bit Controller

Source/Edge
Select
Reload Register Tx
TxIN
SDA 6000
Peripherals
x = 2, 4
Interrupt
Request
TxI
*⁾
Input
Clock
Core Timer T3
Up/Down
T3OTL
Interrupt
Request
T3OUT
T3OE
UES11202
Note: Line ‘*’ is only affected by over/underflows of T3, but NOT by software
modifications of T3OTL.
Figure 7-11 GPT1 Auxiliary Timer in Reload Mode
Upon a trigger signal, T3 is loaded with the contents of the respective timer register (T2
or T4) and the interrupt request flag (T2IR or T4IR) is set.
Note: When a T3OTL transition is selected for the trigger signal, also the interrupt
request flag T3IR will be set upon a trigger, indicating T3’s overflow or underflow.
Modifications of T3OTL via software will NOT trigger the counter function of T2/T4.
The reload mode triggered by T3OTL can be used in a number of different
configurations. Depending on the selected active transition the following functions can
be performed:
• If both a positive and a negative transition of T3OTL are selected to trigger a reload,
the core timer will be reloaded with the contents of the auxiliary timer each time it
overflows or underflows. This is the standard reload mode (reload on overflow/
underflow).
• If either a positive or a negative transition of T3OTL is selected to trigger a reload, the
core timer will be reloaded with the contents of the auxiliary timer on every second
overflow or underflow.
• Using this “single-transition” mode for both auxiliary timers allows very flexible pulse
width modulation (PWM) to be performed. One of the auxiliary timers is programmed
to reload the core timer on a positive transition of T3OTL, the other is programmed for
a reload on a negative transition of T3OTL. With this combination the core timer is
alternately reloaded from the two auxiliary timers.
Users Manual
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2000-06-15