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CHAPTER 14 SERIAL INTERFACE UART6
User’s Manual U16315EJ3V1UD
282
14.3 Registers Controlling Serial Interface UART6
Serial interface UART6 is controlled by the following nine registers.
Asynchronous serial interface operation mode register 6 (ASIM6)
Asynchronous serial interface reception error status register 6 (ASIS6)
Asynchronous serial interface transmission status register 6 (ASIF6)
Clock selection register 6 (CKSR6)
Baud rate generator control register 6 (BRGC6)
Asynchronous serial interface control register 6 (ASICL6)
Input switch control register (ISC)
Port mode register 1 (PM1)
Port register 1 (P1)
(1) Asynchronous serial interface operation mode register 6 (ASIM6)
This 8-bit register controls the serial communication operations of serial interface UART6.
This register can be set by a 1-bit or 8-bit memory manipulation instruction.
RESET input sets this register to 01H.
Remark
ASIM6 can be refreshed (the same value is written) by software during a communication operation
(when bit 7 (POWER6) and bit 6 (TXE6) of ASIM6 = 1 or bit 7 (POWER6) and bit 5 (RXE6) of ASIM6
= 1).
Figure 14-5. Format of Asynchronous Serial Interface Operation Mode Register 6 (ASIM6) (1/2)
Address: FF50H After reset: 01H R/W
Symbol
<7>
<6>
<5>
4
3
2
1
0
ASIM6
POWER6
TXE6
RXE6
PS61
PS60
CL6
SL6
ISRM6
POWER6
Enables/disables operation of internal operation clock
0
Note 1
Disables operation of the internal operation clock (fixes the clock to low level) and asynchronously
resets the internal circuit
Note 2.
1
Note 3
Enables operation of the internal operation clock
TXE6
Enables/disables transmission
0
Disables transmission (synchronously resets the transmission circuit).
1
Enables transmission
Notes 1.
The output of the TXD6 pin goes high and the input from the RXD6 pin is fixed to the high level when
POWER6 = 0.
2.
Asynchronous serial interface reception error status register 6 (ASIS6), asynchronous serial interface
transmission status register 6 (ASIF6), bit 7 (SBRF6) and bit 6 (SBRT6) of asynchronous serial
interface control register 6 (ASICL6), and receive buffer register 6 (RXB6) are reset.
3.
Operation of the 8-bit counter output is enabled at the second base clock after 1 is written to the
POWER6 bit.