M38867E8AHP MITSUBISHI [Mitsubishi Electric Semiconductor], M38867E8AHP Datasheet - Page 38

• Manufacturer Part Number: M38867E8AHP
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER??
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

[Data Bus Buffer Status Register 0, 1
(DBBSTS0, DBBSTS1)] 0029
The data bus buffer status register 0, 1 consist of eight bits.
Bits 0, 1, and 3 are read-only bits and indicate the condition of the
data bus buffer. Bits 2, 4, 5, 6, and 7 are user definable flags
which can be set by program, and can be read/written. This regis-
ter can be read from the host CPU when the A
only.
•Bit 0: Output buffer full flag OBF
•Bit 1: Input buffer full flag IBF
•Bit 3: A
[Input Data Bus Buffer Register 0, 1 (DBBIN0,
DBBIN1)] 0028
Data on the data bus is latched to DBBIN by writing request from
the host CPU. Data of DBBIN can be read from the data bus
buffer registers (address 0028
[Output Data Bus Buffer Register 0, 1
(DBBOUT0, DBBOUT1)] 0028
When writing data to the data bus buffer registers (address 0028
or 002B
output from the host CPU to the data bus by performing the read-
ing request when the A
38
When writing data to the output data bus buffer, these flags are
set to “1”. When reading the output data bus buffer from the host
CPU, these flags are cleared to “0”.
When writing data from the host CPU to the input data bus
buffer, these flags are set to “1”. When reading the input data
bus buffer from the slave CPU side, these flags are cleared to
“0”.
When writing data from the host CPU to the input data bus
buffer, the level of the A
16
0
) on SFR, data is set to DBBOUT. Data of DBBOUT is
flag A0
0
, A0
16
1
0
, 002B
pin is set to “L”.
0
pin is latched.
16
0
16
or 002B
, IBF
0
, OBF
1
16
16
16
1
) on SFR.
, 002C
, 002B
0
pin is set to “H”
16
16
16
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
3886 Group