UPD78F0078GK-9ET-A Renesas Electronics America, UPD78F0078GK-9ET-A Datasheet - Page 277

• Manufacturer Part Number: UPD78F0078GK-9ET-A
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0078GK-9ET-A

• Lead Free Status / Rohs Status: Supplier Unconfirmed

(3) Asynchronous serial interface transmit status register 2 (ASIF2)
Cautions 1. To start successive transmission, be sure to check that TXBF is 0 after the first byte of data
Address: FF95H After reset: 00H
This register indicates the status of transmission.
ASIF2 is set by an 8-bit memory manipulation instruction.
RESET input clears ASIF2 to 00H.
Symbol
ASIF2
Figure 15-5. Format of Asynchronous Serial Interface Transmit Status Register 2 (ASIF2)
2. When successive transmission is in progress, the processing of writing to TXB2 can be
3. To initialize (to set TXE2 to 0 or POWER2 to 0) during successive transmission, make sure
has been written to transmit buffer register 2 (TXB2), then write the second byte of data to
TXB2.
confirmed by checking the value of TXSF after the transmit completion interrupt.
• TXSF = 1: Successive transmission in progress. One-byte data can be written.
• TXSF = 0: Successive transmission is complete. Two-byte data can be written.
that TXSF is 0 after the transmit completion interrupt, then initialize.
TXBF
TXSF
7
0
0
1
0
1
• If bit 7 (POWER2) or bit 6 (TXE2) of asynchronous serial interface mode register 2
• If data is transferred to transmit shift register 2 (TXS2)
If data is written to transmit buffer register 2 (TXB2) (if data exists in TXB2)
• If bit 7 (POWER2) or bit 6 (TXE2) of asynchronous serial interface mode register 2
• If no more data is transferred from transmit buffer register 2 (TXB2) after completion
If data is transferred from transmit buffer register 2 (TXB2) (during transmission)
(ASIM2) is cleared to 0
(ASIM2) is cleared to 0
of transfer.
When writing, note Caution 1 above.
6
0
CHAPTER 15 SERIAL INTERFACE UART2
R
5
0
User’s Manual U14260EJ4V0UD
Transmit shift register data flag
4
0
Transmit buffer data flag
3
0
2
0
TXBF
1
TXSF
0
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