Real-Time Output Port Control Register (Rtpc) - NEC uPD784038 Series User Manual

6.2 REAL-TIME OUTPUT PORT CONTROL REGISTER (RTPC)

The RTPC is an 8-bit register that specifies the function of port 0.
RTPC can be read or written to by an 8-bit manipulation instruction or bit-manipulation instruction. Figure 6-2 shows the format
of RTPC.
RESET input clears the RTPC register to 00H.
Figure 6-2 Real-Time Output Port Control Register (RTPC) Format
7 6
RTPC BYTE 0
Caution When P0ML and P0MH bits are set (to 1), the corresponding port output buffer is turned on and the port
0 output latch contents are output irrespective of the contents of the port 0 mode register (PM0). The
output latch contents should therefore be initialized before making a real-time output port specification.
CHAPTER 6 REAL-TIME OUTPUT FUNCTION
5 4 3 2
0 P0MH EXTR 0
User's Manual U11316EJ4V1UD
1 0 Address After Reset
TRGP0 P0ML 0FF2EH
P0ML P00 to P03 Function Specification
0
Port mode
1 Real-time output port mode
EXTR TRGP0
0 0
1 0
1 1
0 1
P0MH P04 to P07 Function Specification
0
Port mode
Real-time output port mode
1
BYTE Real-Time Output Port Operating Mode
0
4-bit separate real-time output ports
1 8-bit real-time output port
R/W
00H R/W
Enabling of Data Transfer to Output
Latch from P0H, P0L by INTP0
Not enabled
(data transfer by INTC10 only)
Enabled
Transfer by either
• BYTE = 0 :
INTP0 or INTC10
P0L only
transferred
• BYTE = 1 :
Transfer by
P0L/P0H
INTP0 only
transferred
Setting prohibited
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