pcf8813 NXP Semiconductors, pcf8813 Datasheet - Page 52

• Manufacturer Part Number: pcf8813
• Description: 67 + 1 X 102 Pixels Matrix Lcd Driver
• Manufacturer: NXP Semiconductors

Philips Semiconductors
17.5
Instructions additional to those of the instruction set (Table 5) are given in Table 21.
Table 21 Additional instructions
17.5.1
This is a special instruction for the PCF8813 which
disables all included OTP circuitry. In this case, all
OTP-related commands are inactive. V
no effect on V
respectively. Once disabled, the mode can only be
enabled via a reset.
17.5.2
Instruction (MM) enters the device into the calibration
mode. This mode enables the shift register for loading and
allows programming of the non-volatile OTP cells to take
place. If the seal bit is set, then this mode cannot be
accessed and the instruction will be ignored. Once in
calibration mode all commands are interpreted as shift
register data. The mode can only be exited by sending
data with bit D7 set to logic 0. Reset will also clear this
mode. Each shift register data byte is preceded by D/C = 0
and has only three significant bits, thus the remaining five
bits are ignored. Bit D7 is the continuation bit (D7 = 1
indicates remain in MM mode; D7 = 0 indicates exit
MM mode). D6 has to be logic 0 until the last bit when the
seal bit is set, in which case this is set to logic 1 (D6 is set
to logic 1 only when the high voltage used for
programming the cells is about to be applied). Bit D0 is the
data bit and its value is shifted into the OTP shift register
on the falling edge of the SCLK clock.
2004 Mar 05
Reset
Function set
REF (refresh)
Function set
MM
INSTRUCTION
(67 + 1)
Interface commands
D
M
ISABLE
ODULE MAKER CALIBRATION
LCD
OTP
and manufacture identification
102 pixels matrix LCD driver
D/C R/W
0
0
0
0
COMMAND
0
0
0
0
D7
0
0
0
0
CAL
D6
0
0
0
0
and MF have
D5
1
0
1
0
COMMAND BYTE
D4
0
1
0
1
52
D3
0
0
0
1
17.5.3
The action of the refresh instruction (REF) is to force the
OTP shift register to re-load from the non-volatile OTP
cells. This instruction takes up to 5 ms to complete. During
this time all other instructions may be sent.
In the PCF8813, the refresh instruction is associated with
the power control instruction so that the shift register is
refreshed automatically every time the high voltage
generator is enabled or disabled. However, if this
instruction is sent while in Power-down, the PC bits are
updated but the refreshing is ignored.
17.6
An example of the sequence of commands and data for
filling the shift register is shown in Table 22. This example
uses the values V
the Philips identifying code) and the seal bit is 0.
It is assumed that the PCF8813 has just been reset. After
transmitting the last bit the PCF8813 can exit or remain
in MM mode (see Table 22, step 1). When in MM mode,
the interface does not recognize commands in the normal
sense.
After this sequence has been applied, it is possible to
observe the impact of the data shifted in. The sequence
described is not useful for OTP programming because the
number of bits with value = 1 is greater than that allowed
for programming (see Section 17.7). Figure 49 shows the
shift register after this action.
D2
0
0
1
1
Filling the shift register
R
EFRESH
D1
0
0
0
1
PC
D0
CAL
0
1
0
= 4 (11100B), MF = 4 (100B is
enable OTP circuitry
exit Power-down
switch HVgen on/off to force
refresh of shift register
wait 5 ms for refresh to take effect
set PD = 1 and H = 1
enter MM mode
ACTION
Product specification
PCF8813