Rainbow Electronics AT83C26 - Manual (Page 45)

45
7511B–SCR–10/05
AT83C26
Reset value = 0x 0000 X000
Table 24. SC2_CFG0 ()
7 6 5 4 3 2 1 0
VCARD_INT
2
VCARD_OK
2 ATRERR2 INSERT2 X VCARDERR2 VCARD21 VCARD20
Bit Number Bit Mnemonic Description
7 VCARD_INT2
SC2 voltage interrupt
This bit is set when VCARD_OK2 bit is set.
This bit is cleared when read by the micro controller.
6 VCARD_OK2
SC2 Voltage Status
This bit is set by the LD02 when the output voltage remains within the voltage range specified by
VCARD2[1:0] bits.
It is cleared otherwise.
5 ATRERR2
Answer to Reset Interrupt for SC2
This bit is set when the card clock counter overflows (no falling edge on CIO2 is received before the
overflow of the card clock counter).
This bit is cleared by hardware when this register is read. It can be set by software for test purpose.
4 INSERT2
Card Insertion Interrupt
This bit is set when a card is inserted or extracted in SC2 connector: a change in CARDIN2 value filtered
according to CDS2[2-0]. It can be set by software for test purpose.
This bit is cleared by hardware when this register is read. It cannot be cleared by software.
3 X
2 VCARDERR2
Interface 2 Card Out of Range Voltage Interrupt
This bit is set when the output voltage on CVCC
N
goes out of the voltage range specified by VCRDN field. It
can be set by software for test purpose and deactivate the card.
This bit is cleared by hardware when this register is read. It cannot be cleared by software.
The reset value is 0.
1-0 VCARD2[1:0]
Interface 2 Card Voltage Selection
VCRD2[1:0] = 00: 0V
VCRD2[1:0] = 01: 1.8V class C
VCRD2[1:0] = 10: 3V class B
VCRD2[1:0] = 11: 5V class A
No card deactivation is performed when the voltage is changed. The micro controller should deactivate the
card before changing the voltage and activating the card again.
The reset value is 00.