MC72000 Freescale Semiconductor, MC72000 Datasheet - Page 61

• Manufacturer Part Number: MC72000
• Description: Integrated Bluetooth Radio
• Manufacturer: Freescale Semiconductor

RST
RST
RST
RST
W
W
W
W
R
R
R
R
TXLEVEL[7:0]—Transmit Buffer Level
7.2.5.4.3
UCTS sets the threshold for the CTS control flow signal. If the remote UART continues to send limited
amounts of data after detecting the deasserted CTS signal, the local receive buffer can handle the additional
data if CTS_LEVEL is set to a suitable value.
CTS_LEVEL[7:0]—CTS Buffer Level
7.2.5.5 UART Baud Rate Divider Register (UBR)
The fractional divider registers are used to select the receive and transmit baud rate. The following sections
describe the fractional divider registers.
The FRACDIV_DIV register is used to select the divisor for the fractional division divider. See
Section 7.2.3, “Fractional Divider,” for an explanation of the value to be written to the register.
The FRACDIV_INC register is used to select the modulus value for the fractional division divider. See
Section 7.2.3, “Fractional Divider,” for an explanation of the value to be written to the register.
UBRINC — INC Value
UBRMOD — MOD Value
MOTOROLA
When the number of free bytes in the transmit FIFO buffer exceeds the value specified by TXLEVEL,
an interrupt is generated.
When the number of bytes in the receiver (RX) FIFO exceeds this value, the CTS signal is deasserted.
This value is used to select the baud rate. See Section 7.2.3, “Fractional Divider,” for more information.
This value is used to select the baud rate. See Section 7.2.3, “Fractional Divider,” for more information.
31
15
31
15
0
0
0
0
= writes have no effect and terminate without transfer error exception
= writes have no effect and terminate without transfer error exception
30
14
30
14
0
0
0
0
UART CTS Level Control Register (UCTS)
29
13
29
13
0
0
0
0
28
12
28
12
0
0
0
0
Freescale Semiconductor, Inc.
For More Information On This Product,
MC72000 Advance Information Data Sheet
27
11
27
11
0
0
0
0
26
10
26
10
Go to: www.freescale.com
0
0
0
0
UBR
UCTSBase + $014
25
25
0
9
0
0
9
0
Preliminary
Base + $018
UBRMOD
UBRMOD
24
24
0
8
0
UBRINC
UBRINC
0
8
0
23
23
0
7
0
0
7
0
22
22
0
6
0
0
6
0
Hardware Functional Description
21
21
0
5
0
0
5
0
CTS_LEVEL
CTS_LEVEL
20
20
0
4
0
0
4
0
19
19
0
3
0
0
3
0
18
18
0
2
0
0
2
0
17
17
0
1
0
0
1
0
61
16
16
0
0
0
0
0
0