cs5954am Cypress Semiconductor Corporation., cs5954am Datasheet - Page 14

• Manufacturer Part Number: cs5954am
• Description: Usb Controller For Nand Flash
• Manufacturer: Cypress Semiconductor Corporation.

4.10.2
The Speed Control Register allows the CS5954AM processor to operate at a number of speed selections. A four-bit divider
(SPD3–0 + 1) selects the speed as shown below. Speed will also depend on the clock multiplier. See Configuration Register
(0xC006: R/W) for more information.
4.10.3
During power down mode, the peripherals are put in a “pause” state. All counters and timers stop incrementing.
There are two ways to enter power-down mode: Suspend or Halt.
Note:
Document #: 38-08025 Rev. **
10. Upon reset, the lowest speed is selected for low-power operation. The CS5954AM BIOS will configure the clock to 24 MHz as part of its initialization.
D15–D6
D3–D0
D15–D4
D5
D4
D3–D2
D1
This mode ends with a transition on either USB or any Interrupt. It is followed by a delay set in the power-up delay bit fields.
D0
D15–D6
0
Speed Control Register (0xC008: R/W)
Power-down Control Register (0xC00A: R/W)
D15–D4
PUD1
0
0
0
1
1
SPD3–0
0000
0001
0010
0100
0101
1000
1001
1010
0011
0110
1011
1100
1101
0111
1110
1111
SPD3–SPD0
Reserved
USB
GPIO
PUD1–PUD0
SUSPEND
HALT
Reserved
USB
D5
GPIO
SPD3
D4
D3
Speed selection bits
should be set to all zeros.
Enable restarts on USB transition resulting in device power-up.
Enable restarts on GPIO transition resulting in device power-up (see GPIO Interrupt
Control Register (0xC01C:R/W)).
Power-up Delay Selection. Four delays are provided and selected using these select
bits. This is time from power-up until processor starts executing allowing clock to settle.
ends with an interrupt.
should be set to all zeros.
To save power, Suspend mode stops all clocks in the CS5954AM.
PUD0
0
1
0
1
ADVANCE
INFORMATION
PUD1
D3
SPD2
0 milliseconds
1 milliseconds
8 milliseconds
64 milliseconds
D2
PUD0
D2
CS5954AM Speed
48.00 MHz
24.00 MHz
16.00 MHz
12.00 MHz
09.60 MHz
08.00 MHz
06.86 MHz
06.00 MHz
05.33 MHz
04.80 MHz
04.36 MHz
04.00 MHz
03.69 MHz
03.42 MHz
03.20 MHz
03.00 MHz
Power-up Delay
SPD1
D1
SUSPEND
[10]
D1
CS5954AM
SPD0
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D0
HALT
D0