Operation Of Serial Interface Uart6; Operation Stop Mode - NEC 78K0S/KB1+ User Manual

11.4 Operation of Serial Interface UART6

Serial interface UART6 has the following two modes.

• Operation stop mode

• Asynchronous serial interface (UART) mode
11.4.1 Operation stop mode
In this mode, serial communication cannot be executed; therefore, the power consumption can be reduced. In
addition, the pins can be used as ordinary port pins in this mode. To set the operation stop mode, clear bits 7, 6, and
5 (POWER6, TXE6, and RXE6) of ASIM6 to 0.
(1) Register used
The operation stop mode is set by asynchronous serial interface operation mode register 6 (ASIM6).
ASIM6 can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation sets this register to 01H.
Address: FF90H After reset: 01H R/W
Symbol <7>
ASIM6 POWER6
POWER6
Note 1
0
TXE6
0
RXE6
0
Notes 1. The output of the T
POWER6 = 0 during a transmission.
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.
Caution Clear POWER6 to 0 after clearing TXE6 and RXE6 to 0 to set the operation stop mode.
To start the operation, set POWER6 to 1, and then set TXE6 and RXE6 to 1.
Remark To use the RxD6/P44 and TxD6/INTP1/P43 pins as general-purpose port pins, see CHAPTER 4 PORT
FUNCTIONS.
CHAPTER 11 SERIAL INTERFACE UART6
<6> <5>
TXE6 RXE6
Enabling/disabling operation of internal operation clock
Disable operation of the internal operation clock (fix the clock to low level) and asynchronously
Note 2
reset the internal circuit .
Disable transmission operation (synchronously reset the transmission circuit).
Disable reception (synchronously reset the reception circuit).
D6 pin goes high and the input from the R
X
User's Manual U17446EJ3V1UD
4 3
PS61 PS60 CL6
Enabling/disabling transmission
Enabling/disabling reception
X
2 1
SL6 ISRM6
D6 pin is fixed to high level when
0
195