CHAPTER 12 BIT SEQUENTIAL BUFFER
User’s Manual U14826EJ5V0UD
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12.3 Bit Sequential Buffer Control Register
The bit sequential buffer is controlled by the following three registers.
•
Bit sequential buffer output control register 10 (BSFC10)
•
Port mode register 2 (PM2)
•
Port 2 (P2)
(1) Bit sequential buffer output control register 10 (BSFC10)
BSFC10 controls the operation of the bit sequential buffer.
This register is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input clears this register to 00H.
Figure 12-2. Format of Bit Sequential Buffer Output Control Register 10
Symbol
7 6 5 4 3 2 1
<0>
Address
After
reset
R/W
BSFC10
0 0 0 0 0 0 0
BSFE10
FF60H
00H
R/W
BSFE10
Bit sequential buffer operation control
0
Operation
disabled
1
Operation
enabled
(2) Port mode register 2 (PM2)
PM2 sets port 2 to input/output in 1-bit units.
When using the P20/TMO/BSFO pin as a data output of the bit sequential buffer, clear the PM20 and P20
output latch to 0.
This register is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input sets this register to FFH.
Figure 12-3. Format of Port Mode Register 2
Symbol
7 6 5 4 3 2 1 0
Address
After
reset
R/W
PM2
1 1 1 1 1 1
PM21
PM20
FF22H
FFH
R/W
PM20
P20 pin input/output mode
0
Output mode (output buffer on)
1
Input mode (output buffer off)