Infineon GPT12 - Reload Values Calculation

Implementation
Reload Values calculation example
Calculating the correct reload value to generate a PWM signal, depending on the given
frequency f and duty cycle, is done in the initialization function initGpt12PWM():
› Get the GPT12 module base frequency 𝑓
𝐺𝑃𝑇
by calling the iLLD function
IfxGpt12_getModuleFrequency()
› Calculate the timer frequency with the following formula:
The GPT1 block prescaler is set to IfxGpt12_Gpt1BlockPrescaler_32, 𝑓
𝐺𝑃𝑇
is divided by 32
The timer prescaler is set to IfxGpt12_TimerInputPrescaler_32, 𝑓
𝐺𝑃𝑇
is divided by 32
› Calculate dutyUpTime and dutyDownTime with the following formulas:
𝑓
𝑡𝑖𝑚𝑒𝑟
=
𝑓
𝐺𝑃𝑇
GPT1_BLOCK_PRESCALER × TimerInputPrescaler
𝒅𝒖𝒕𝒚𝑼𝒑𝑻𝒊𝒎𝒆 =
𝑓
𝑡𝑖𝑚𝑒𝑟
×
𝑑𝑢𝑡𝑦𝐶𝑦𝑐𝑙𝑒
100
𝑓
𝒅𝒖𝒕𝒚𝑫𝒐𝒘𝒏𝑻𝒊𝒎𝒆 =
𝑓
𝑡𝑖𝑚𝑒𝑟
× 1 −
𝑑𝑢𝑡𝑦𝐶𝑦𝑐𝑙𝑒
100
𝑓
7
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