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EPSON
S1C63406 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Serial Interface)
EPR: Parity enable register (FF71HD3)
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, 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 setting becomes invalid in the clock synchronous
mode.
At initial reset, this register is set to "0".
PMD: Parity mode selection register (FF71HD2)
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, 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. When "0" has
been written to EPR, the parity setting by PMD becomes invalid.
At initial reset, this register is set to "0".
TXEN: Transmit enable register (FF72HD0)
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, the serial interface shifts to the transmit enabled status and shifts to the
transmit disabled status when "0" is written.
Set TXEN to "0" when making the initial settings of the serial interface and similar operations.
At initial reset, this register is set to "0".
TXTRG: Transmit trigger/status (FF72HD1)
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 after writing the transmitting data.
TXTRG can be read as the status. When set to "1", it indicates transmitting operation, and "0" indicates
transmitting stop.
At initial reset, TXTRG is set to "0".