13 counter timer lower register (0x1c)-ctlr, 14 codec clock register (0x20)-ccr, Counter timer lower register (0x1c)—ctlr -20 – Freescale Semiconductor MPC5200B User Manual
Page 534: Counter timer lower register (0x1c)—ctlr, Codec clock register (0x20)—ccr, Ctlr, Section 15.2.13, counter timer, Lower register (0x1c)—ctlr, 13 counter timer lower register (0x1c)
PSC Registers—MBAR + 0x2000, 0x2200, 0x2400, 0x2600, 0x2800, 0x2C00
MPC5200B Users Guide, Rev. 1
Freescale Semiconductor
15-23
15.2.13
Counter Timer Lower Register (0x1C)
—
CTLR
This write-only register hold the lower bytes of the preload value used by the timer to provide a given Baud rate. Reading from this register
shows the current value of the Baud rate generation counter.
DTL — Length of Delay after Transfer
When the PSC is in SPI mode (
[SPI] = 1), the Counter Timer is used to determine the length of time that the PSC delays after each
serial transfer, i. E. the length of time that SS stays high/inactive between consecutive transfers. This is a feature that exists in a QSPI.
Delay after transfer can be used to ensure that the deselect time requirement (for peripherals having such a requirement) is met. Some
peripherals must be deselected for a minimum period of time between consecutive serial transfers. A delay after transfer can be inserted
between consecutive transfers to a given peripheral to ensure that its minimum deselect time requirement is met or to allow serial A/D
converters to complete conversion before the next transfer is made.
15.2.14
Codec Clock Register (0x20)—CCR
This register defines the divider for the FrameSync and BitClk generation for Codec mode. This register value has only effect, if the GenClk
bit in the PSC Control Register
was set to one. In UART, SIR and AC97 mode this register is reserved.
Table 15-31. Counter Timer Lower Register (0x1C) for all Modes
msb 0
1
2
3
4
5
6
7 lsb
R
Reserved
W
CTLR[0:7]
RESET:
0
0
0
0
0
0
0
0
Bit
Name
Description
0:7
CTLR
UART—Baud rate prescale value. The Baud rate is calculated as:
The minimum CT value is 1; 0 denotes counter stop.
The prescaler was defined in the
register.
SIR—Baud rate prescale value. The Baud rate is calculated as:
The minimum CT value is 1; 0 denotes counter stop.
SPI—Delay After Transfer (DTL)
Other—Reserved
Table 15-32. Codec Clock Register (0x20)—CCR for Codec Mode
msb
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 lsb
RESET:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
Baud rate =
CT[0:15] x “prescaler”
IPB clock frequency
where:
CT[0:15] = {
[0:7]}
Baud rate =
CT[0:15] x 32
IPB clock frequency
where:
CT[0:15] = {
[0:7]}
DTL =
IPB clock frequency
CT[0:15] + 2
where:
CT[0:15] = {
[0:7]}
+
3
Mclk frequency
]