Specifications

Table Of Contents

S1C62740 TECHNICAL HARDWARE EPSON I-33

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)

Output Ports (R00–R03)4.5

Configuration of

output ports

The S1C62740 has four bits general output ports.

Output specifications of the output ports can be selected individu-

ally with the mask option. Two kinds of output specifications are

available: complementary output and Nch open drain output.

Further, each of the output port to be used as special output ports

by the software setting.

Figure 4.5.1 shows the configuration of the output port.

Fig. 4.5.1

Configuration of output port

Output specifications of the output ports can be selected with the

mask option.

Output specifications for the output ports (R00–R03) enable

selection of either complementary output or Nch open drain output

for each of the four bits.

However, even when Nch open drain output is selected, voltage

exceeding source voltage must not be applied to the output port.

Mask option

Special output

In addition to the regular DC output, special output can be se-

lected as shown in Table 4.5.1 with the software. Figure 4.5.2

shows the structure of the output ports R00–R03.

Terminal Special output Output selection register

R00 FOUT FOR00

R01 PTOVF PTR01

R02 BZ BZR02

R03 BZ BZR03

Table 4.5.1

Special output

Data bus

Address

Nch open drain

Complementary

Mask option