YMF744B ETC [List of Unclassifed Manufacturers], YMF744B Datasheet - Page 43

• Manufacturer Part Number: YMF744B
• Description: DS-1S
• Manufacturer: ETC [List of Unclassifed Manufacturers]

YMF744B
2-3. MPU401
2-4. Joystick
F8h: Interrupt Flag Register
2-2-4. SB IRQ Status
b0................SBI: SB Interrupt Flag
The following shows the MPUBase I/O map for MPU401.
+1h (W)
This bit indicates that the SB DSP occurs the interrupt. This bit is read only. Thus, read the SB DSP
read port to clearing the interrupt and this bit. Then, the value of the read port is invalid.
This block is for transmitting and receiving MIDI data. It is compatible with UART mode of “MPU401”.
Full duplex operation is possible using the 16-byte FIFO for each direction, transmitting and receiving.
JSBase
JACX...
JACY...
JBCX...
JBCY...
JAB1...
JAB2...
JBB1...
JBB2...
+1h (R)
b7
-
port
+0h
port
+0h
Read Only
Default: 00h
MPUBase
MPUBase + 1h
MPUBase + 1h
b6
-
/DSR
JBB2
D7
D7
(R/W)
Joystick A, Coordinate X
Joystick A, Coordinate Y
Joystick B, Coordinate X
Joystick B, Coordinate Y
Joystick A, Button 1
Joystick A, Button 2
Joystick B, Button 1
Joystick B, Button 2
b5
-
/DRR
JBB1
D6
D6
b4
(R/W)
(R)
(W)
-
b3
-
JAB2
D5
D5
-
MIDI Data port
Status Register port
Command Register port
b2
-
JAB1
D4
D4
-
Command
-43-
b1
-
Data
JBCY
SBI
D3
D3
b0
-
JBCX
D2
D2
-
JACY
D1
D1
-
JACX
D0
D0
February 3, 1999
-