LED Pulse Generator
7-100
7.9
LED Pulse Generator
The LED pulse generator (LPG) module controls an indication LED (see
Figure 7–43). The blinking period is programmable between 152 ms and 4s,
and the LED can be switched on permanently. The OMAP5910 device has two
LPG modules. Each LPG module drives a single output pin on the OMAP5910
device which can be used to switch an LED driver.
Figure 7–43. LED Pulse Generator Block Diagram
LED
Bus
decoders
3 to 10
and
3 to 5
Programmable
Divider
Synchronous
or
nstrobe
CLK32K
Reset
lpgres
perm_on
lpg_led
clk_256
perctrl
onctrl
perlpg
onlpg
TIPB
interface
control logic
for
output
and
counter
counter and
comparator
pulse
generator
Two
1
7.9.1
Features
The LPG has the following features:
-
Divider generating a 256-Hz frequency clock
-
TIPB control interface
-
Two 8-bit registers to control the whole LPG block
-
Decoder for three blink frequency control bits (LPG2-0)
-
Decoder for three pulse width control bits (LPG5-3)
-
Programmable counter with integrated comparison for the PWM
-
Synchronous control logic for the output and the counter
-
Multiplexer to generate a faster clock for testing