Rainbow Electronics T89C5121 - Manual (Page 40)

40
A/T8xC5121
4164G–SCR–07/06
Table 17. SCISR Register
SCISR (S:ADh, SCRS = 0)
Smart Card UART Interface Status Register
Reset Value = 1000 0000b
7 6 5 4 3 2 1 0
SCTBE CARDIN CIccOVF CVccOK SCWTO SCTC SCRC SCPE
Bit
Number
Bit
Mnemonic Description
7 SCTBE
SCIB transmit buffer empty
This bit is set by hardware when the Transmit Buffer is copied to the transmit shift
register of the Smart Card UART.
It is cleared by hardware when SCTBUF is written to.
6 CARDIN
Card presence status
This bit is set when a card is detected (debouncing filter has to be done in
software).
It is cleared otherwise.
5 CIccOVF
ICC overflow on card
This bit is set when the current on card is above the limit
It shall be cleared by the hardware .
4 CVccOK
Card voltage status
This bit is set when the output voltage is within the voltage range specified by
CVcc field.
It is cleared otherwise.
3 SCWTO
Smart card wait Timeout
This bit is set by hardware when the Smart card wait time counter times out.
It shall be cleared by the reload of the counter or by the reset of the SCIB.
2 SCTC
Smart card transmitted character
This bit is set by hardware when the Smart Card UART has transmitted a
character.
It shall be cleared by software after this register has been read.
1 SCRC
Smart card received character
This bit is set by hardware when the Smart Card UART has received a character
It is cleared by hardware when SCBUF is read.
0 SCPE
Smart card parity error
This bit is set at the same time as SCTI or SCRI if a parity error is detected.
It shall be cleared by software after this register has been read.