M30222 Datasheet, PDF (128/237 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

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in
this
manual
are
tentative
and
subject
to
MITSUBISHI
change
MICROCOMPUTERS
Rev. G
Clock Asynchronous Serial I/O Mode
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(a) Function for outputting a parity error signal
With the error signal output enable bit (bit 7 of address 037D16) assigned “1”, you can output an “L” level
from the TxD2 pin when a parity error is detected. In step with this function, the generation timing of a trans-
mission completion interrupt changes to the detection timing of a parity error signal. Figure 1.101 shows the
output timing of the parity error signal.
• LSB first
Transfer “H”
clock “L”
RxD2 “H”
“L”
TxD2 “H”
“L”
Receive “1”
complete flag “0”
ST D0 D1 D2 D3 D4 D5 D6 D7 P SP
Hi-Z
Fig. 1.101. Output timing of the parity error signal
ST : Start bit
P : Even Parity
SP: Stop bit
(b) Direct format/inverse format
Connecting the SIM card allows you to switch between direct format and inverse format. If you choose the
direct format, D0 data is output from TxD2. If you choose the inverse format, D7 data is inverted and output
from TxD2. Figure 1.102 shows the SIM interface format. Figure 1.103 shows the example of connecting the
SIM interface. Connect TXD2 and RXD2 and apply pull-up.
Transfer
clock
TxD2
(direct)
ST D0 D1 D2 D3 D4 D5 D6 D7 P SP
TxD2
(inverse)
ST _{D7 D6 D5 D4 D3 D2 D1 D0}
P _SP
P : Even parity
ST: Start bit
SP: Stop bit
Fig. 1.102. SIM interface format
Microcomputer
TxD2
RxD2
SIM card
Fig. 1.103. Connecting the SIM interface
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