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CHAPTER 20 UART2, UART3
20.6.2
Reload Counter
This is the 15-bit reload counter that works as a dedicated baud rate generator, and
generates the transmission/reception clock through the external or internal clock.
In addition, it can read the value of the transmission reload counter from the baud rate
generator registers (BGR02/BGR03, BGR12/BGR13).
■ Function of the Reload Counter
The reload counter has a transmission and reception reload counters that works as the dedicated baud rate
generator. It consists of the 15-bit resister for the reload value, and generates the transmission/reception
clock through the external or internal clock. In addition, it can read the value of the transmission reload
counter from the baud rate generator registers (BGR02/BGR03, BGR12/ BGR13).
■ Start of the Count
When a reload value is written into the baud rate generator registers (BGR02/BGR03, BGR12/BGR13), the
reload counter starts counting.
■ Restarting the Reload Counter
The Reload Counters can be restarted of the following reasons:
Transmission and reception reload counter:
• Global MCU reset
• UART2, UART3 programmable clear (SMR2/SMR3:UPCL bit)
• User programmable restart (SMR2/SMR3:REST bit)
Reception reload counter:
• Automatic restart (Start bit falling edge detection in asynchronous mode)
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Programmable Restart
If the REST bit of the Serial Mode Register (SMR2/SMR3) is set by the user, both Reload Counters are
restarted at the next clock cycle. This feature is intended to use the Transmission Reload Counter as a small
timer.
The following figure illustrates a possible usage of this feature (assume that the reload value is 100.)
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