Rainbow Electronics T89C5121 - Manual (Page 43)

43
A/T8xC5121
4164G–SCR–07/06
Table 20. SCSR Register
SCSR (S:ABh) Smart Card Selection Register
Reset Value = XXX0 1000b
Table 21. SCTBUF Register
SCTBUF (S:AA, write-only, SCRS = 0) Smart Card Transmit Buffer Register
Reset Value = 0000 0000b
7 6 5 4 3 2 1 0
- - - CREPSEL ALTKPS1 ALTKPS0 SCCLK1 SCRS
Bit
Number
Bit
Mnemonic Description
7 - Reserved
6 - Reserved
5 - Reserved
4 CREPSEL
Character repetition selection
Clear this bit to select 5 times repetition before parity error indication
Set this bit to select 4 times repetition before parity error indication
3-2
ALTKPS1
ALTKPS0
Alternate Card Clock prescaler factor
00ALTKPS = 0: prescaler factor equals 1
01ALTKPS = 1: prescaler factor equals 2
10ALTKPS = 2: prescaler factor equals 4 (reset value)
11ALTKPS = 3: prescaler factor equals 8
1 SCCLK1
Alternate card clock selection
Set to select the prescaled clock (CCLK1)
Clear to select the standard port configuration (P3.6)
0 SCRS
Smart card register selection
The SCRS bit selects which set of the SCIB registers is accessed.
7 6 5 4 3 2 1 0
Bit Number Bit Mnemonic Description
– –
Can store a new byte to be transmitted on the I/O pin when SCTBE is set.
Bit ordering on the I/O pin depends on the Convention (see SCICR
Register).