Lock Read Register (Lrrh, Lrrl) - Fujitsu F2MC-16LX MB90580 Series Hardware Manual

13.3.9 Lock read register (LRRH, LRRL)

Lock read register (LRRH, LRRL)
Address: 00007B
H
Reserved Reserved
Read/write
Initial value
Address: 00007A
H
Read/write
Initial value
[bit 15-13] Reserved bits:
Always reading '1' from these bits.
[bit 12] LOC (Lock check):
This bit indicates the status whether the unit is locked or not from other unit.
0 Does not lock
1 Locked
Writing '0' to this bit will unlock the unit itself. Writing '1' to this bit has no meaning.
[bit 11-0] LD11 - LD00 (Lock address):
These bits store the lock address, the address of the master that has executed locking to the unit.
When the unit is not locked. there is no meaning for these bits.
Note: In IEBus communication, the lock function is used to transmit a message over two
or more communication frames. If the master that has executed locking was down
before executing the unlocked command, the locked unit cannot receive data
anymore. So in order to prevent such condition, the unit in the system that
supporting lock function need checking the lock status periodically by reading this
lock read register. And the unit can unlock itself by writing '0' to LOC bit..
MB90580 Series
15 14 13
Reserved
(R)
(R)
(R/W)
(1) (1)
(1)
7 6 5
LD07 LD06 LD05
(R) (R)
(R)
(X) (X)
(X)
12 11 10
LOC LD11 LD10
(R)
(R) (R)
(X)
(0) (X)
4 3 2
LD04 LD03 LD02
(R) (R)
(R)
(X) (X)
(X)
13.3 Registers and Register Details
9 8
LD09 LD08
(R)
(R)
(X)
(X)
1 0
LD01 LD00
(R)
(R)
(X)
(X)
Chapter 13: IE Bus
Bit Number
LRRH
Bit Number
LRRL
157