cs5535 National Semiconductor Corporation, cs5535 Datasheet - Page 153

• Manufacturer Part Number: cs5535
• Description: Geode Cs5535 Companion Multi-function South Bridge
• Manufacturer: National Semiconductor Corporation

Revision 0.8
4.16 MULTI-FUNCTION GENERAL PURPOSE TIMER
The Multi-Function General Purpose Timer module con-
tains
(MFGPTs). Six of the eight MFGPTs are in the Working
power domain running off a 32 kHz clock or a 14.318 MHz
clock, while the other two are in the Standby power domain
running off a 32 kHz clock.
The Working power domain contains the following blocks:
• Six MFGPTs each split into three blocks, one containing
• 15-bit prescaler to divide down the 14.318 MHz clock
• 15-bit prescaler to divide down the 32 kHz clock and
• Logic to implement Local Bus Interface, Control Logic,
• Two blocks containing I/O registers to write into the two
The Standby power domain contains the following blocks:
• Two MFGPTs.
• 15-bit prescaler to divide down the 32 kHz clock and
• Interface for signals going between Standby and
Figure 4-50 shows the top level block diagram of the Multi-
Function General Purpose Timer module.
Features
Each MFGPT operates independently and can have the
following features:
• 32 kHz or 14.318 MHz clock selectable by software
• Programmable input clock prescaler divisor to divide
• Watchdog timer (trigger GPIO output, interrupt, or
• Pulse Width Modulation (PWM).
• Pulse Density Modulation (PDM).
• Blink (low frequency pulse for LED).
• General Purpose Timer.
• Generate GPIO outputs.
• Provide outputs for generating reset (limited to MFGPT0
I/O registers, one containing the clock switch, and one
containing the timer logic.
and generate 15 carry-out signals.
generate 15 carry-out signals.
MSR Registers, and NMI, IRQ, and Reset Output
Events.
MFGPTs in the Standby power domain.
generate 15 carry-out signals.
Working power domains.
(MFGPT0 to MFGPT5 only; MFGPT6 and MFGPT7 use
32 kHz clock).
input clock by 2
reset).
to MFGPT5), IRQs, NMI, and ASMI (indirectly through
PIC).
eight
multi-function
i
, where i = 0 to 15.
general
purpose
timers
153
Figure 4-50. MFGPT System Top Level Block
I/O Reg I/F
Control and MSR Registers
MFGPT6
Power Domain Crossing I/F
MFGPT6
I/O Reg Clock
I/O Reg Clock
I/O Reg Clock
I/O Reg Clock
I/O Reg Clock
I/O Reg Clock
Timer
Standby Domain
Working Domain
Diagram
14.318 MHz
Prescaler
Prescaler
Prescaler
MFGPT0
MFGPT1
MFGPT2
MFGPT3
MFGPT4
MFGPT5
32 kHz
Switch
Switch
Switch
Switch
Switch
Switch
32kHz
I/O Reg I/F
MFGPT7
MFGPT7
Timer
Timer
Timer
Timer
Timer
Timer
Timer
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