III PERIPHERAL BLOCK: SERIAL INTERFACE
The interrupt priority register sets the interrupt priority level of each interrupt source in a range between 0 and
7. An interrupt request to the CPU is accepted only when no other interrupt request of a higher priority has been generated.
In addition, only when the PSR's IE bit = "1" (interrupts enabled) and the set value of the IL is smaller than the input interrupt level set by the interrupt priority register, will the input interrupt request actually be accepted by the CPU.
For details on these interrupt control registers, as well as the device operation when an interrupt has occurred, refer to "ITC (Interrupt Controller)".
•Ch.2 and Ch.3
Ch.2 and Ch.3 do not have dedicated interrupt signals. Either a port input interrupt or
The correspondence between port input interrupt factors and
Table 8.10 Correspondence between Interrupt Factors
Serial I/F Ch.2, Ch.3/ | Port input interrupt | |
factor | factor | |
T8 Ch.5 UF | FPT7 | Timer 2 compare A |
T8 Ch.4 UF | FPT5 | Timer 2 compare B |
SIO Ch.3 TXD Emp. | FPT6 | Timer 4 compare A |
SIO Ch.3 RXD Full | FPT4 | Timer 4 compare B |
SIO Ch.3 RXD Err. | FPT2 | Timer 3 compare A |
SIO Ch.2 TXD Emp. | FPT3 | Timer 5 compare A |
SIO Ch.2 RXD Full | FPT1 | Timer 5 compare B |
SIO Ch.2 RXD Err. | FPT0 | Timer 3 compare B |
Switching between the above interrupt factors is performed by means of the interrupt factor FP function switching register (0x402C5) and the interrupt factor TM16 function switching register (0x402CB).
For the setting of the interrupt controller in the
Intelligent DMA
•Ch.0 and Ch.1
The
The following shows the IDMA channel numbers set for each interrupt factor:SIF IDMA Ch.
0x17
0x18
0x19
0x1A
The IDMA request and enable bits shown in Table 8.11 must be set to "1" for IDMA to be invoked. Transfer conditions, etc. on the IDMA side must also be set in advance.
| Table 8.11 | Control Bits for IDMA Transfer | ||
Channel | Interrupt factor |
| IDMA request bit | IDMA enable bit |
Ch.0 |
| RSRX0(D6/0x40292) | DESRX0(D6/0x40296) | |
|
| RSTX0(D7/0x40292) | DESTX0(D7/0x40296) | |
Ch.1 |
| RSRX1(D0/0x40293) | DESRX1(D0/0x40297) | |
|
| RSTX1(D1/0x40293) | DESTX1(D1/0x40297) |
S1C33L03 FUNCTION PART | EPSON |