71M6534H Demo Board User’s Manual
Page: 59 of 86
© 2005-2007 TERIDIAN Semiconductor Corporation
V2-0
2.5.3 RTC
Testing the RTC inside the 71M6534/6534H IC is straightforward and can be done using the serial command
line interface (CLI) of the Demo Code.
To set the RTC and check the time and date, we apply the following sequence of CLI commands:
>M10
LCD display to show calendar date
>RTD05.09.27.3
Sets the date to 9/27/2005 (Tuesday)
>M9
LCD display to show time of day
>RTT10.45.00
Sets the time to 10:45:00. AM/PM distinction: 1:22:33PM = 13:22:33
2.5.4 HARDWARE WATCHDOG TIMER (WDT)
The hardware WDT of the 71M6534/6534H is disabled when the voltage at the V1 pin is at 3.3V (V3P3). On the
Demo Boards, this is done by plugging in a jumper at TP10 between the V1 and V3P3 pins.
Conversely, removing the jumper at TP10 will enable the WDT. When the WDT is enabled, typing “W” at the
command line interface will cause the Demo Board to reset.
2.5.5 LCD
Various tests of the LCD interface can be performed with the Demo Board, using the serial command line
interface (CLI):
Setting the LCD_EN register to 1 enables the display outputs.
Register Name
Address [bits]
R/W
Description
LCD_EN
2021[5]
R/W
Enables the LCD display. When disabled, VLC2, VLC1, and
VLC0 are ground, as are the COM and SEG outputs.
To access the
LCD_EN
register, we apply the following CLI commands:
>RI21$
Reads the hex value of register 0x2021
>25
Response from Demo Code indicating the bit 5 is set
>RI21=5
Writes the hex value 0x05 to register 0x2021 causing the display to be switched off
>RI21=25
Sets the
LCD_EN
register back to normal
The
LCD_CLK
register determines the frequency at which the COM pins change states. A slower clock means
lower power consumption, but if the clock is too slow, visible flicker can occur. The default clock frequency for
the 71M6534/6534H Demo Boards is 150Hz (
LCD_CLK
= 01).
Register Name
Address [bits]
R/W
Description
LCD_CLK[1:0]
2021[1:0]
R/W
Sets the LCD clock frequency, i.e. the frequency at which SEG
and COM pins change states.
f
w
= 32,768Hz
00:
f
w
/2
9
, 01: f
w
/2
8
, 10: f
w
/2
7
, 11: f
w
/2
6
To change the LCD clock frequency, we apply the following CLI commands:
>RI21$
Reads the hex value of register 0x2021
>25
Response from Demo Code indicating the bit 0 is set and bit 1 is cleared.
Содержание 71M6534H
Страница 2: ...71M6534H Demo Board User s Manual Page 2 of 86 2005 2007 TERIDIAN Semiconductor Corporation V2 0...
Страница 8: ...71M6534H Demo Board User s Manual Page 8 of 86 2005 2007 TERIDIAN Semiconductor Corporation V2 0...
Страница 40: ...71M6534H Demo Board User s Manual Page 40 of 86 2005 2007 TERIDIAN Semiconductor Corporation V2 0...