Document No.: FT_000138
VINCULUM-II EMBEDDED DUAL USB HOST CONTROLLER IC Datasheet
Version -
1.2
Clearance No.: FTDI#
143
Time
t10
t11
t12
t13
t14
Description
CLKOUT TO TXE#
Write DATA setup time
Write DATA hold time
WR# setup time
WR# hold time
Minimum
Typical
Maximum
Unit
ns
ns
ns
ns
ns
1
12
0
12
0
7.83
Table 31 S
ynchronous
FIFO mode Read / Write Timing
6.8 General Purpose Timers
In VNC2 there are 4 General Purpose Timers available. Three are available to the designer and one is
reserved for the RTOS.
The timers have the following features:
16 bit
Count down
One shot and auto-reload
enable
Interrupt on zero
6.9 Pulse Width Modulation
VNC2 provides 8 Pulse Width Modulation (PWM) outputs. These can be used to generate PWM signals
which can be used to control motors, DC/DC converters, AC/DC supplies, etc. Further information is
available in an Application Note AN_140 -
The features of the PWM module are as follows:
-
-
-
-
-
-
8 PWM outputs
A trigger input
8-bit prescaler
16-bit counter
Generation of up to 4-pulse signal with controlled output enable and configurable initial state
Interrupt
A single PWM cycle can have up to 4 pulses (8 edges). The PWM block uses a 16-bit counter to
determine the period of a single PWM cycle. This counter counts system clocks which can also be divided
by an optional 8-bit prescaler. The PWM drivers allow the user to select when PWM output toggles. These
values correspond to the values of 16-bit counter. For example, on the timing diagram below -
the 16-bit counter counts to 23 and pwm_out[0] output toggles when the counter‟s current value
is equal to 7, 8, 12, 14, 15, 16, 19 and 22.
Figure 6-24 PWM – Timing Diagram
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