w65c22 Western Design Center, Inc., w65c22 Datasheet - Page 12

• Manufacturer Part Number: w65c22
• Description: W65c22n And W65c22s Versatile Interface Adapter Via Datasheet
• Manufacturer: Western Design Center, Inc.

2.4
Write Handshake Control.
The Write Handshake operation is similar to Read Handshaking. For Write Handshaking, however, the
W65C22 generates the Data Ready signal and the peripheral device must generate the Data Taken return
signal. Note that Write Handshaking may occur on both PA and PB. For a Write Handshake, CA2 or CB2
serve as the Data Ready output and can operate in either the Handshake Mode or the Pulse Mode. The
Data Taken signal is received the CA1 or CB1. The Data Taken signal sets a flag in the Interrupt Flag
Register and clears the Data Ready output signal, see Figure 2-2.
Note that the selection of Read or Write Handshake operating modes for CA1, CA2, CB1 and CB2 is
accomplished by the Peripheral Control Register (PCR). See Table 2-5.
Figure 2-2 Write Handshake (PA and PB)
Table 2-5 CA1, CA2, CB1, CB2 Control ($0C)
7
6
5
4
3
2
1
0
PCR
CB2 Control
CB1
CA2 Control
CA1
Control
Control
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