ST52T430K3M6 STMicroelectronics, ST52T430K3M6 Datasheet - Page 63

• Manufacturer Part Number: ST52T430K3M6
• Manufacturer: STMicroelectronics

Specifications of ST52T430K3M6

• Cpu Family: ST52
• Device Core Size: 8b
• Frequency (max): 20MHz
• Interface Type: SCI/UART
• Program Memory Type: EPROM
• Program Memory Size: 8KB
• Total Internal Ram Size: 256Byte
• # I/os (max): 23
• Number Of Timers - General Purpose: 3
• Operating Supply Voltage (typ): 3.3/5V
• Operating Supply Voltage (max): 5.5/5.8V
• Operating Supply Voltage (min): 2.7/3V
• On-chip Adc: 8-chx8-bit
• Instruction Set Architecture: CISC
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 34
• Package Type: SSO
• Lead Free Status / Rohs Status: Not Compliant

When the SCI Receiver is in IDLE status, it is
waiting for the START condition, which is obtained
with a logic level 0, consecutive to a logic level 1.
This condition is detected if a logic level 0 is
sampled after three logic levels 1 with the fixed
sampling time.
The recognition of the START bit forces the SCI
Receiver Block to enter in a data acquisition
sequence. The data acquisition sequence is
configured via Configuration Register 20 as
follows.
The 2 bits, M, of the Configuration Register 20
allows the definition of the serial mode as
illustrated in Table 11.1.
In the case that M=10,
parity check in order to perform (as indicated in
Table 11.1).
Recognition of the STOP condition allows data
received from the Recovery Buffer to be
transferred to the SCDR_RX buffer, adding the
eventual ninth data bit, according to the meaning
illustrated in previous Table 11.1. After this
operation, the RXF flag of the SCI Status Input
Register 19 (Figure 11.3) is set to logic level 1. The
Control Unit reads data from the SCDR_RX buffer
(in read-only mode) with the LDRI instruction,
addressing Input Register 18, and provides a reset
at logic level 0 to the RXF flag.
If data of the Recovery Buffer is ready to be
transferred into the SCDR_RX buffer, but the
previous one was not read by the Core yet, an
OVERRUN Error takes place: the status flag
OVERR indicates the error condition. In this case,
the information stored in the SCDR_RX buffer is
not altered, but the one that has caused the
OVERRUN error can be overwritten by new data
deriving from the serial data line.
Recovery Buffer Block
This block is structured as a synchronized finite
state machine on the CLOCK_RX signal.
When the Recovery Buffer Block is in IDLE state it
waits for the reception of the correct 1 and 0
sequence representing START.
The recognition takes place by sampling the input
RX/PC5 at CLOCK_RX frequency, which has a
frequency that is 16 times higher than CLOCK_TX.
While the external transmitter sends a single bit,
the Recovery Buffer Block samples 16 states (from
SAMPLE1 to SAMPLE16).
The analysis of the RX/PC5 input signal is carried
out providing three samples for each bit received.
If these three samples are not equal, then the
noise error flag, NSERR, of Input Register 19 is set
to 1 and the data value received will be the one
assumed by the majority of the samples.
is used to set the
The procedure above allows SCI not to become
IDLE, because of a limited noise due to “an
erroneous
recognized as correct and the noise flag is set.
Table 11.1 Configuration Register 20 Setting
At the end of the reception of a bit, Recovery Buffer
Block will repeat the same step 9 times: one for the
stop acquisition (10 times in case of 9-bit data,
double stop or parity check).
At the end of data reception the Recovery Buffer
Block will supply information on eventual frame
errors by setting the FRERR flag bit of Input
Register 19 to 1.
Bit
0
1
2
3
4
5
6
7
Name
BRSL
RE
TE
T8
M
sampling”.
Value
000
001
010
100
101
011
110
111
00
01
10
11
0
1
0
1
0
1
The
Transmission ENABLED
Parity Even, if Parity is
8, No Parity, 1 bit stop
8, No Parity, 2 bit stop
9, No Parity, 1 bit stop
otherwise 9th Data bit
otherwise 9th Data bit
Parity Odd, if Parity is
Receiver DISABLED
Receiver ENABLED
8, Parity, 1 bit stop
selected (M
selected (M = 10);
ST52T430/E430
Transmission
Description
19200 baud
38400 baud
transmission
1200 baud
4800 baud
9600 baud
2400baud
600 baud
Not Used
10);
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is