Datasheet

ADuC7128/ADuC7129
Rev. 0 | Page 61 of 92
Table 85. COMxSTA1 MMR Bit Designations
Bit Name Description
7 DCD Data Carrier Detect.
6 RI Ring Indicator.
5 DSR Data Set Ready.
4 CTS Clear to Send.
3 DDCD Delta Data Carrier Detect.
Set automatically if DCD changed state since COMxSTA1 last read.
Cleared automatically by reading COMxSTA1.
2 TERI Trailing Edge Ring Indicator.
Set if NRI changed from 0 to 1 since COMxSTA1 last read.
Cleared automatically by reading COMxSTA1.
1 DDSR Delta Data Set Ready.
Set automatically if DSR changed state since COMxSTA1 last read.
Cleared automatically by reading COMxSTA1.
0 DCTS Delta Clear to Send.
Set automatically if CTS changed state since COMxSTA1 last read.
Cleared automatically by reading COMxSTA1.
Table 86. COMxDIV2 MMR Bit Designations
Bit Name Description
15 FBEN Fractional Baud Rate Generator Enable Bit.
Set by user to enable the fractional baud rate generator.
Cleared by user to generate baud rate using the standard 450 UART baud rate generator.
14:13 RSVD Reserved.
12:11 FBM[1 to 0] M, if FBM = 0, M = 4 (see the Using the Fractional Divider section).
10:0 FBN[10 to 0] N (see the Using the Fractional Divider section).
Network Addressable UART Mode
This mode allows connecting the MicroConverter on a 256-node
serial network, either as a hardware single master or via software
in a multimaster network. Bit 7 of COMxIEN1 (ENAM bit)
must be set to enable UART in network-addressable mode.
Note that there is no parity check in this mode. The parity bit is
used for address.
Network Addressable UART Register Definitions
Four additional registers, COMxIEN0, COMxIEN1, COMxIID1,
and COMxADR are used only in network addressable UART
mode.
In network address mode, the least significant bit of the
COMxIEN1 register is the transmitted network address control
bit. If set to 1, the device is transmitting an address. If cleared
to 0, the device is transmitting data. For example, the following
master-based code transmits the slave address followed by the data:
COM0IEN1 = 0xE7; //Setting ENAM, E9BT, E9BR, ETD, NABP
COM0TX = 0xA0; // Slave address is 0xA0
while(!(0x020==(COM0STA0 & 0x020))){} // wait for adr tx to finish.
COM0IEN1 = 0xE6; // Clear NAB bit to indicate Data is coming
COM0TX = 0x55; // Tx data to slave: 0x55