Sharp MZ-3500 General description of the parallel interface, Output, Data transfer timing

Models: MZ-3500

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7-3. General description of the parallel interface

The 8255 is used for the LSI to control the parallel inter- face. The 8255 can be set in the following mode.

/PORT A: MODE 0

IPORTB: MODE 1

C:Output

74.Data transfer timing

BUSY

ACK

( 8255 A

vPC-7J

DATA

STROBE

( M 1 N ) l^s(MIN)

Because it is not possible to directly it uses interrupt for key processing ACK signal is latched by means of

sense the ACK signal as and RS232C input, the the OBF pin function

PRINTER: MZ-1P02, MZ-1P03 CE-

330P, 331P, 332P

*Broken line in the above figure represents timing for the CE-330Pand331P.

'For detail of timing, refer to Manual provided with printer.

7-5. General description of control software

Set the 20 second counter.

STROBE OUT

Set the 20 second counter.

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Sharp MZ-3500 service manual General description of the parallel interface, Output, Data transfer timing