beautypg.com

NEC PD17062 User Manual

Page 205

background image

205

µ

PD17062

16.1.3 SIO0MS

The SIO0MS flag specifies the serial interface clock to be used.

When the SIO0MS flag is set to 0, the external clock is selected. When the SIO0MS flag is set to 1, the internal

clock is selected. When the internal clock is selected, its frequency is set by the shift clock frequency register

(RF: 39H).

When the SIO0MS flag is set to 0 in two-wire bus mode, slave operation is specified. When the SIO0MS

flag is set to 1 in two-wire bus mode, master operation is specified.

Table 16-6 SIO0MS Flag Functions

16.1.4 SIO0TX

If the SIO0TX flag is set to 0 in two-wire bus mode, reception mode is specified. If the SIO0TX flag is set

to 1 in two-wire bus mode, transmission mode is specified.

If the SIO0TX flag becomes 0 upon specifying CH0 serial I/O mode, SI mode (the SDA pin is in input mode)

is specified. If the SIO0TX flag becomes 1 upon specifying CH0 serial I/O mode, SO mode (the SDA pin is in

output mode) is specified.

When the CH1 serial I/O mode is specified, the SIO0TX flag specifies whether the SO pin is to be used as

a serial interface. When the SIO0TX flag is set to 1, the SO pin is used as an SO pin. When the SIO0TX flag

is set to 0, the SO pin is used as a general-purpose port.

Table 16-7 SIO0TX Flag Functions

SIO0MS

Function

0

Two-wire bus mode : Slave operation

Serial I/O mode

: External clock operation

1

Two-wire bus mode : Master operation

Serial I/O mode

: Internal clock operation

SIO0TX

Function

0

Two-wire bus mode : RX (reception) mode

CH0 serial I/O mode : SI mode

CH1 serial I/O mode : P0A

3

is used as a general-purpose port

1

Two-wire bus mode : TX (transmission) mode

CH0 serial I/O mode : SO mode

CH1 serial I/O mode : P0A

3

is used as an SO pin