ST7263-EMU2 STMicroelectronics, ST7263-EMU2 Datasheet - Page 59

• Manufacturer Part Number: ST7263-EMU2
• Description: MCU, MPU & DSP Development Tools ST7 Emulator Board
• Manufacturer: STMicroelectronics

Specifications of ST7263-EMU2

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

SERIAL COMMUNICATIONS INTERFACE (Cont’d)
5.5.4.4 Baud Rate Generation
The baud rates for the receiver and transmitter (Rx
and Tx) are set independently and calculated as
follows:
with:
PR = 1, 3, 4 or 13 (see SCP0 & SCP1 bits)
TR = 1, 2, 4, 8, 16, 32, 64,128
(see SCT0, SCT1 & SCT2 bits)
RR = 1, 2, 4, 8, 16, 32, 64,128
(see SCR0,SCR1 & SCR2 bits)
All these bits are in the BRR register.
Example: If f
TR=RR=1, the transmit and receive baud rates are
19200 bauds.
Note: The baud rate registers MUST NOT be
changed while the transmitter or the receiver is en-
abled.
5.5.4.5 Receiver Muting and Wake-up Feature
In multiprocessor configurations it is often desira-
ble that only the intended message recipient
Tx =
(32
f
CPU
*
PR)
CPU
*
TR
is 8 MHz and if PR=13 and
Rx =
(32
f
CPU
*
PR)
*
RR
should actively receive the full message contents,
thus reducing redundant SCI service overhead for
all non addressed receivers.
The non addressed devices may be placed in
sleep mode by means of the muting function.
Setting the RWU bit by software puts the SCI in
sleep mode:
All the reception status bits can not be set.
All the receive interrupt are inhibited.
A muted receiver may be awakened by one of the
following two ways:
– by Idle Line detection if the WAKE bit is reset,
– by Address Mark detection if the WAKE bit is set.
The Receiver wakes-up by Idle Line detection
when the Receive line has recognised an Idle
Frame. Then the RWU bit is reset by hardware but
the IDLE bit is not set.
The Receiver wakes-up by Address Mark detec-
tion when it received a “1” as the most significant
bit of a word, thus indicating that the message is
an address. The reception of this particular word
wakes up the receiver, resets the RWU bit and
sets the RDRF bit, which allows the receiver to re-
ceive this word normally and to use it as an ad-
dress word.
ST7263
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