Epson S1C63558 4.5.6 Programming notes, CRMO: R11 output selection register (FF13H•D1), CHDO: R12 output selection register (FF13H•D2)

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 (VSS) 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 fOSC3 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.

40 EPSON S1C63558 TECHNICAL MANUAL