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EPSON
S1C63558 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)
CRMO: R11 output selection register (FF13H•D1)
Selects the R11 terminal function.
When "1" is written: XRMUTE output
When "0" is written: General-purpose DC output
Reading: Valid
When using the R11 terminal for the XRMUTE output, write "1" to this register. Furthermore, fix the R11
register at "1" and the R11HIZ register at "0". Refer to Section 4.14, "Telephone Function", for controlling
the XRMUTE output.
When using the R11 output port for a general-purpose output, fix this register at "0".
At initial reset, this register is set to "0".
CHDO: R12 output selection register (FF13H•D2)
Selects the R12 terminal function.
When "1" is written: HDO output
When "0" is written: General-purpose DC output
Reading: Valid
When using the R12 terminal for the HDO output, write "1" to this register. Furthermore, fix the R12
register at "1" and the R12HIZ register at "0". Refer to Section 4.14, "Telephone Function", for controlling
the HDO output.
When using the R12 output port for a general-purpose output, fix this register at "0".
At initial reset, this register is set to "0".
CHFO: R13 output selection register (FF13H•D3)
Selects the R13 terminal function.
When "1" is written: HFO output
When "0" is written: General-purpose DC output
Reading: Valid
When using the R13 terminal for the HFO output, write "1" to this register. Furthermore, fix the R13
register at "1" and the R13HIZ register at "0". Refer to Section 4.14, "Telephone Function", for controlling
the HFO output.
When using the R13 output port for a general-purpose output, fix this register at "0".
At initial reset, this register is set to "0".
4.5.6 Programming notes
(1) When using an output port (R00–R03, R10–R13) for special output, fix the corresponding data register
(R00–R03, R10–R13) at "1" and the high impedance control register (R00HIZ–R03HIZ, R10HIZ–
R13HIZ) at "0" (data output).
Be aware that the output terminal is fixed at a low (V
SS
) level the same as the DC output if "0" is
written to the data registers when the special output has been selected.
Be aware that the output terminal shifts into high impedance status when "1" is written to the high
impedance control register.
(2) A hazard may occur when the TOUT, FOUT , BZ or XBZ signal is turned ON and OFF.
(3) When f
OSC3
is selected for the FOUT signal frequency, it is necessary to control the OSC3 oscillation
circuit before output.
Refer to Section 4.3, "Oscillation Circuit", for the control and notes.