Samsung S3C2451X User Manual page 365

S3C2451 RISC MICROPROCESSOR
UART MODEM STATUS REGISTER
There are three UART modem status registers including UMSTAT0, UMSTAT1 in the UART block.
Register
UMSTAT0 0x5000001C
UMSTAT1 0x5000401C
UMSTAT2 0x5000801C
Reserved 0x5000C01C
UMSTAT0
Delta CTS
Reserved [3:1]
Clear to Send
Delta CTS
Read_UMSTAT
Address R/W
R UART channel 0 modem status register
R UART channel 1 modem status register
R UART channel 2 modem status register
– Reserved
Bit
[4] Indicate that the nCTS input to the S3C2451X has changed state
since the last time it was read by CPU.
(Refer to Figure 15-8.)
0 = Has not changed
1 = Has changed
–
[0] 0 = CTS signal is not activated (nCTS pin is high)
1 = CTS signal is activated (nCTS pin is low)
nCTS
Figure 15-8. nCTS and Delta CTS Timing Diagram
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
Description
Description
UART
Reset Value
0x0
0x0
0x0
Undef
Initial State
0
0
0
15-17