HT1622
Name
ID
Command Code
101X-0000-X
D/C
Function
Def.
Time base clock output: 1Hz
1 0 0
F1
C
The WDT time-out flag after: 4s
Time base clock output: 2Hz
1 0 0
1 0 0
1 0 0
1 0 0
1 0 0
1 0 0
1 0 0
F2
101X-0001-X
101X-0010-X
101X-0011-X
101X-0100-X
101X-0101-X
101X-0110-X
101X-0111-X
C
C
C
C
C
C
C
The WDT time-out flag after: 2s
Time base clock output: 4Hz
F4
The WDT time-out flag after: 1s
Time base clock output: 8Hz
F8
The WDT time-out flag after: 1/2s
Time base clock output: 16Hz
F16
F32
F64
The WDT time-out flag after: 1/4s
Time base clock output: 32Hz
The WDT time-out flag after: 1/8s
Time base clock output: 64Hz
The WDT time-out flag after: 1/16s
Time base clock output: 128Hz
F128
Yes
Yes
The WDT time-out flag after: 1/32s
1 0 0
1 0 0
TEST
1110-0000-X
1110-0011-X
C
C
Test mode, user don¢t use.
NORMAL
Normal mode
Note:
X : Don¢t care
A5~A0 : RAM address
D3~D0 : RAM data
D/C : Data/Command mode
Def. : Power on reset default
All the bold forms, namely 1 1 0, 1 0 1, and 1 0 0, are mode commands. Of these, 1 0 0 indicates the command
mode ID. If successive commands have been issued, the command mode ID except for the first command will
be omitted. The source of the tone frequency and of the time base or WDT clock frequency can be derived from
an on-chip 32kHz RC oscillator or an external 32kHz clock. Calculation of the frequency is based on the sys-
tem frequency sources as stated above. It is recommended that the host controller should initialize the HT1622
after power on reset, for power on reset may fail, which in turn leads to the malfunctioning of the HT1622.
Rev. 1.40
11
February 6, 2007
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
