Interrupts In Smart Card Interface Mode - Renesas H8S/2100 Series Hardware Manual

15.8.2

Interrupts in Smart Card Interface Mode

Table 15.14 shows the interrupt sources in smart card interface mode. A TEI interrupt request
cannot be used in this mode.
Table 15.14 SCI Interrupt Sources
Channel Name
1 ERI1
RXI1
TXI1
2 ERI2
RXI2
TXI2
In transmission, the TEND and TDRE flags in SSR are simultaneously set to 1, thus generating a
TXI interrupt request. If an error occurs, the SCI automatically re-transmits the same data. During
re-transmission, the TEND flag remains 0. Therefore, the SCI automatically transmits the
specified number of bytes, including re-transmission in the case of error. However, the ERS flag
in SSR, which is set at error occurrence, is not automatically cleared; the ERS flag must be cleared
by previously setting the RIE bit in SCR to 1 to enable an ERI interrupt request to be generated at
error occurrence.
In reception, an RXI interrupt request is generated when the RDRF flag in SSR is set to 1. If an
error occurs, the RDRF flag is not set but the error flag is set. Therefore, an ERI interrupt request
is issued to the CPU instead; the error flag must be cleared.
Interrupt Source
Receive error, error signal
detection
Receive data full
Transmit data empty
Receive error, error signal
detection
Receive data full
Transmit data empty
Section 15 Serial Communication Interface (SCI)
Interrupt Flag
ORER, PER, ERS
RDRF
TEND
ORER, PER, ERS
RDRF
TEND
Rev. 1.00 Apr. 28, 2008 Page 461 of 994
Priority
High
Low
REJ09B0452-0100