Renesas H8S/2111B Hardware Manual page 440

Serial Interrupt Transfer Cycle
Frame
Count Contents
0 Start
1 IRQ0
2 IRQ1
3 SMI
4 IRQ3
5 IRQ4
6 IRQ5
7 IRQ6
8 IRQ7
9 IRQ8
10 IRQ9
11 IRQ10
12 IRQ11
13 IRQ12
14 IRQ13
15 IRQ14
16 IRQ15
17 IOCHCK
18 Stop
There are two modes—continuous mode and quiet mode—for serialized interrupts. The mode
initiated in the next transfer cycle is selected by the stop frame of the serialized interrupt transfer
cycle that ended before that cycle.
In continuous mode, the host initiates host interrupt transfer cycles at regular intervals. In quiet
mode, the slave processor with interrupt sources requiring a request can also initiate an interrupt
transfer cycle, in addition to the host. In quiet mode, since the host does not necessarily initiate
interrupt transfer cycles, it is possible to suspend the clock (LCLK) supply and enter the power-
down state. In order for a slave to transfer an interrupt request in this case, a request to restart the
clock must first be issued to the host. For details see section 15.4.6, Host Interface Clock Start
Request (CLKRUN).
Rev. 1.00, 05/04, page 406 of 544
Drive Number
Source of States
Slave 6
Host
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Slave 3
Host Undefined
Notes
In quiet mode only, slave drive possible in first
state, then next 3 states 0-driven by host
Drive possible in LPC channel 1
Drive possible in LPC channels 2 and 3
Drive possible in LPC channels 2 and 3
Drive possible in LPC channels 2 and 3
Drive possible in LPC channels 2 and 3
Drive possible in LPC channels 2 and 3
Drive possible in LPC channel 1
First, 1 or more idle states, then 2 or 3 states
0-driven by host
2 states: Quiet mode next
3 states: Continuous mode next