CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Serial Interface)

EPR: Serial interface (1) parity enable register (FF71H•D3)EPRS: Serial interface (2) parity enable register (FF59H•D3)

Selects the parity function.

When "1" is written: With parity

When "0" is written: Non parity

Reading: Valid

Selects whether or not to check parity of the received data and to add a parity bit to the transmitting data. When "1" is written to EPR/EPRS, the most significant bit of the received data is considered to be the parity bit and a parity check is executed. A parity bit is added to the transmitting data. When "0" is written, neither checking is done nor is a parity bit added.

Parity is valid only in asynchronous mode and the EPR/EPRS setting becomes invalid in the clock synchronous mode.

At initial reset, this register is set to "0".

PMD: Serial interface (1) parity mode selection register (FF71H•D2)PMDS: Serial interface (2) parity mode selection register (FF59H•D2)

Selects odd parity/even parity.

When "1" is written: Odd parity

When "0" is written: Even parity

Reading: Valid

When "1" is written to PMD/PMDS, odd parity is selected and even parity is selected when "0" is written. The parity check and addition of a parity bit is only valid when "1" has been written to EPR/EPRS. When "0" has been written to EPR/EPRS, the parity setting by PMD/PMDS becomes invalid.

At initial reset, this register is set to "0".

TXEN: Serial interface (1) transmit enable register (FF72H•D0)TXENS: Serial interface (2) transmit enable register (FF5AH•D0)

Sets the serial interface to the transmit enabled status.

When "1" is written: Transmit enabled

When "0" is written: Transmit disabled

Reading: Valid

When "1" is written to TXEN/TXENS, the serial interface shifts to the transmit enabled status and shifts to the transmit disabled status when "0" is written.

Set TXEN/TXENS to "0" when making the initial settings of the serial interface and similar operations. At initial reset, this register is set to "0".

TXTRG: Serial interface (1) transmit trigger/status (FF72H•D1)TXTRGS: Serial interface (2) transmit trigger/status (FF5AH•D1)

Functions as the transmit start trigger and the operation status indicator (transmitting/stop status).

When "1" is read: During transmitting

When "0" is read: During stop

When "1" is written: Start transmitting

When "0" is written: Invalid

Starts transmitting when "1" is written to TXTRG/TXTRGS after writing the transmitting data. TXTRG/TXTRGS can be read as the status. When set to "1", it indicates transmitting operation, and "0" indicates transmitting stop.

At initial reset, TXTRG/TXTRGS is set to "0".

S1C63558 TECHNICAL MANUAL

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