User Manual

AT75C220
85
USART Mode Register
Name: US_MR
Access Type:Read/write
Reset Value:0x0
• USCLKS: Clock Selection (Baud Rate Generator Input Clock)
• CHRL: Character Length
Start, stop and parity bits are added to the character length.
• SYNC: Synchronous Mode Select
0 = USART operates in asynchronous mode.
1 = USART operates in synchronous mode.
• PAR: Parity Type
31 30 29 28 27 26 25 24
––––––––
23 22 21 20 19 18 17 16
–––––CLKO MODE9 –
15 14 13 12 11 10 9 8
CHMODE NBSTOP PAR SYNC
76543210
CHRL USCLKS ––––
USCLKS Selected Clock
00
ACLK
01
ACLK/8
1X
External (SCK)
CHRL Character Length
00
Five bits
01
Six bits
10
Seven bits
11
Eight bits
PAR Pa r ity Ty pe
000
Even parity
001
Odd parity
010
Parity forced to 0 (space)
011
Parity forced to 1 (mark)
10x
No parity
11x
Multi-drop mode