UPD78F0537DGA(T)-9EV-A NEC, UPD78F0537DGA(T)-9EV-A Datasheet - Page 742

• Manufacturer Part Number: UPD78F0537DGA(T)-9EV-A
• Description: 8BIT MCU, 128K FLASH, 7KB RAM, SMD
• Manufacturer: NEC

Specifications of UPD78F0537DGA(T)-9EV-A

• Controller Family/series: UPD78
• No. Of I/o's: 55
• Ram Memory Size: 7KB
• Cpu Speed: 20MHz
• No. Of Timers: 8
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 128KB
• Oscillator Type: External, Internal

742
Serial
interface
UART6
Serial
interface
CSI10,
CSI11
Function
ASICL6:
Asynchronous serial
interface control
register 6
POWER6, TXE6,
RXE6: Bits 7, 6, 5 of
ASIM6
UART mode
Parity types and
operation
Continuous
transmission
Normal reception
Error of baud rate
Permissible baud rate
range during reception
SOTB1n: Transmit
buffer register 1n
Details of Function
The read value of the SBRT6 bit is always 0. SBRT6 is automatically cleared to
0 after SBF reception has been correctly completed.
Before setting the SBTT6 bit to 1, make sure that bit 7 (POWER6) and bit 6
(TXE6) of ASIM6 = 1. After setting the SBTT6 bit to 1, do not clear it to 0 before
SBF transmission is completed (before an interrupt request signal is generated).
The read value of the SBTT6 bit is always 0. SBTT6 is automatically cleared to
0 at the end of SBF transmission.
Do not set the SBRT6 bit to 1 during reception, and do not set the SBTT6 bit to
1 during transmission.
Before rewriting the DIR6 and TXDLV6 bits, clear the TXE6 and RXE6 bits to 0. p. 369
Clear POWER6 to 0 after clearing TXE6 and RXE6 to 0 to stop the operation.
To start the communication, set POWER6 to 1, and then set TXE6 or RXE6 to
1.
Take relationship with the other party of communication when setting the port
mode register and port register.
Fix the PS61 and PS60 bits to 0 when the device is used in LIN communication
operation.
The TXBF6 and TXSF6 flags of the ASIF6 register change from “10” to “11”,
and to “01” during continuous transmission. To check the status, therefore, do
not use a combination of the TXBF6 and TXSF6 flags for judgment. Read only
the TXBF6 flag when executing continuous transmission.
When the device is use in LIN communication operation, the continuous
transmission function cannot be used. Make sure that asynchronous serial
interface transmission status register 6 (ASIF6) is 00H before writing transmit
data to transmit buffer register 6 (TXB6).
To transmit data continuously, write the first transmit data (first byte) to the
TXB6 register. Be sure to check that the TXBF6 flag is “0”. If so, write the next
transmit data (second byte) to the TXB6 register. If data is written to the TXB6
register while the TXBF6 flag is “1”, the transmit data cannot be guaranteed.
To initialize the transmission unit upon completion of continuous transmission,
be sure to check that the TXSF6 flag is “0” after generation of the transmission
completion interrupt, and then execute initialization. If initialization is executed
while the TXSF6 flag is “1”, the transmit data cannot be guaranteed.
During continuous transmission, the next transmission may complete before
execution of INTST6 interrupt servicing after transmission of one data frame.
As a countermeasure, detection can be performed by developing a program
that can count the number of transmit data and by referencing the TXSF6 flag.
If a reception error occurs, read ASIS6 and then RXB6 to clear the error flag.
Otherwise, an overrun error will occur when the next data is received, and the
reception error status will persist.
Reception is always performed with the “number of stop bits = 1”. The second
stop bit is ignored.
Be sure to read asynchronous serial interface reception error status register 6
(ASIS6) before reading RXB6.
Keep the baud rate error during transmission to within the permissible error
range at the reception destination.
Make sure that the baud rate error during reception satisfies the range shown in
(4) Permissible baud rate range during reception.
Make sure that the baud rate error during reception is within the permissible
error range, by using the calculation expression shown below.
Do not access SOTB1n when CSOT1n = 1 (during serial communication).
In the slave mode, transmission/reception is started when data is written to
SOTB11 with a low level input to the SSI11 pin. For details on the
transmission/reception operation, see 16.4.2 (2) Communication operation.
APPENDIX D LIST OF CAUTIONS
User’s Manual U17260EJ6V0UD
Cautions
p. 369
p. 369
p. 369
p. 369
p. 371
p. 372
p. 375
p. 377
p. 377
p. 377
p. 377
p. 377
p. 381
p. 381
p. 381
p. 388
p. 388
p. 389
p. 394
p. 394
(16/25)
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