UPD78F0537DGA(T)-9EV-A NEC, UPD78F0537DGA(T)-9EV-A Datasheet - Page 377

• 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

(d) Continuous transmission
The next transmit data can be written to transmit buffer register 6 (TXB6) as soon as transmit shift register 6
(TXS6) has started its shift operation. Consequently, even while the INTST6 interrupt is being serviced after
transmission of one data frame, data can be continuously transmitted and an efficient communication rate
can be realized. In addition, the TXB6 register can be efficiently written twice (2 bytes) without having to wait
for the transmission time of one data frame, by reading bit 0 (TXSF6) of asynchronous serial interface
transmission status register 6 (ASIF6) when the transmission completion interrupt has occurred.
To transmit data continuously, be sure to reference the ASIF6 register to check the transmission status and
whether the TXB6 register can be written, and then write the data.
Cautions 1. The TXBF6 and TXSF6 flags of the ASIF6 register change from “10” to “11”, and to “01”
Caution To transmit data continuously, write the first transmit data (first byte) to the TXB6 register.
The communication status can be checked using the TXSF6 flag.
Cautions 1. To initialize the transmission unit upon completion of continuous transmission, be sure
2. When the device is use in LIN communication operation, the continuous transmission
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.
2. During continuous transmission, the next transmission may complete before execution
TXBF6
TXSF6
0
1
0
1
during continuous transmission.
combination of the TXBF6 and TXSF6 flags for judgment. Read only the TXBF6 flag
when executing 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 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.
of INTST6 interrupt servicing after transmission of one data frame.
countermeasure, detection can be performed by developing a program that can count
the number of transmit data and by referencing the TXSF6 flag.
Writing enabled
Writing disabled
Transmission is completed.
Transmission is in progress.
CHAPTER 15 SERIAL INTERFACE UART6
User’s Manual U17260EJ6V0UD
Writing to TXB6 Register
Transmission Status
To check the status, therefore, do not use a
As a
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