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CHAPTER 17
IEBus CONTROLLER (
PD178096A, 178098A, 178F098 ONLY)
User’s Manual U12790EJ2V0UD
Because in (4) and (5) the communication was from other than the unit that sent the lock request while the
IEBus was in the locked state, the start or communication complete interrupt (INTIE2) is not generated, even
if the IEBus unit is the communication target. The STATUSF flag (bit 4 of the IEBus interrupt status register
(ISR)) is set and the status interrupt request (INTIE2) generated, however, if a slave status or lock address
request is acknowledged. Note that even if the same control data is received while the IEBus is in the locked
state, the interrupt generation timing for INTIE2 differs depending on whether the master unit (3) or another
unit (4) is requesting the locked state.
Figure 17-18. Timing of INTIE2 Interrupt Generation in Locked State (for (4) and (5))
Note The telegraph length and data modes are not set in the case of (5) because ACK is not returned.
Remark
P: Parity bit, A: ACK/NACK bit
Figure 17-19. Timing of INTIE2 Interrupt Generation in Locked State (for (3))
Remark
P: Parity bit, A: ACK/NACK bit
INTIE2
IEBus sequence
Status
interrupt
Start
Master address
(12 + P)
Broad-
cast
Slave address
(12 + P + A)
Control
(4 + P + A)
Telegraph
lengthNote
(8 + P + A)
DataNote
(8 + P + A)
INTIE2
IEBus sequence
Status
interrupt
Start
Master address
(12 + P)
Broad-
cast
Slave address
(12 + P + A)
Control
(4 + P + A)
Telegraph length
(8 + P + A)
Communication
complete interrupt
Data
(8 + P + A)
Start
interrupt