AT83EC5123 ATMEL Corporation, AT83EC5123 Datasheet - Page 46

• Manufacturer Part Number: AT83EC5123
• Description: (AT8xx512x) Smart Card Reader ICs
• Manufacturer: ATMEL Corporation

46
AT8xC5122/23
Table 40. Smart Card Contacts Register - SCCON (S:ACh, SCRS=0)
Reset Value = 0X00 0000b
Number
CLK
Bit
7
7
6
5
4
3
2
1
0
Mnemonic
CARDVCC
CARDCLK
CARDRST
CARDC8
CARDC4
CARDIO
CLK
6
Bit
-
-
CARDC8
Description
Card Clock Selection
Clear this bit to use the Card CLK bit (CARDCLK) to drive Card CLK pin.
Set this bit to use XTAL or PLL signal to drive the Card CLK pin.
Note: internal synchronization avoids glitches on the CLK pin when switching
this bit.
Reserved
The value read from this bit is indeterminate. Do not change this bit.
Card C8
Clear this bit to drive a low level on the Card C8 pin.
Set this bit to set a high level on the Card C8 pin.
The CC8 pin can be used as a pseudo bi-directional I/O when this bit is set.
Card C4
Clear this bit to drive a low level on the Card C4 pin.
Set this bit to set a high level on the Card C4 pin.
The CC4 pin can be used as a pseudo bi-directional I/O when this bit is set.
Card I/O
When the UART bit is cleared in Registers, the value of this bit is driven to the
Card I/O pin.
Then this pin can be used as a pseudo bi-directional I/O when this bit is set.
To be used as an input, this bit must contain a 1.
Card CLK
When the CLK bit is cleared in SCCON Register, the value of this bit is driven
to the Card CLK pin.
Card RST
Clear this bit to drive a low level on the Card RST pin.
Set this bit to set a high level on the Card RST pin.
Card VCC Control
Clear this bit to desactivate the Card interface and set its power-off. The other
bits of SCCON register have no effect while this bit is cleared.
Set this bit to power-on the Card interface. The activation sequence should be
handled by software.
5
CARDC4
4
CARDIO
3
CARDCLK
2
CARDRST
1
4202B–SCR–07/03
CARDVCC
0