Sony VPL-PX32 Service Manual page 36

2. USB Projector Controller IC: IC3304 (ST72T36)
In the USB communication between the personal computer and MAIN CPU of the projector, the
enable signal: Low (Pin 42 of IC3303) of the microprocessor cable hub for performing protocol
conversion (USB-IC) is input to the Q3310 base, Q3310 goes OFF, this Pin 8 of IC3304 becomes
high, and reset is canceled.
The projector control signal executed by the application projector station for the projector on the
personal computer is input to Pins 31 and 32 of IC3304 via the HUB (IC3303). This signal is
analyzed and sent to the MAIN CPU by I
Basically, this IC is the master while the MAIN CPU is the salve.
To send the projector information (input signals, etc.) to the personal computer, the MAIN CPU
converts the signal line USB REQ to Low. When this signal is input to Pin 7, this IC requests for
projector information using I
3. IrDA Circuit
The remote control signal (IrDA) received by the infrared photo-sending unit (NF/NR M't) in front
and at the back of the projector is input to the IrDA filter IC (IC3301) (NF;Pin 2, NR;Pin 3).
In IC3301, the photo-sensing unit effective signal (NF;Pin 7, NR;Pin 6) by the MAIN CPU is enabled
= low, and the signal determined as a useful IrDA signal is output from Pin 5. While it is input as the
SIRCS signal to the MAIN CPU via the SIRCS circuit (QD), it is input to Pin 1 of IC3302 (Pin 2 is
fixed at low), the reverse signal is output from Pin 7, input to Pin 2 and 6 of IC3002, and Pin 7:IrDA,
Pin 3:IrDB are output to the QB board and QC board,
If INPUT-A is selected, the control signal mouse A/B becomes high by the MAIN CPU, and
consequently, Pin 1 of IC3002 becomes high (Pin 5:Low), the IrDA signal is output only from Pin 7,
and Pin 3 is prohibited.
3-5-3. Memory
Memory structure of VPL-PX32 series is based on the 600 series, and it is composed of the following five
memory blocks.
1. Set memory
2. Status memory
3. Channel memory
4. Chroma memory
5. W/B memory
The 600 series is equipped with the gamma memory, but the current VPL-PX32 series is no gamma
memory. The gamma mode function is realized by applying the offset to the output value of the contrast
and the brightness of the devices as X2000 series.
When the power plug is connected to the power line (Standby status), all data inside the internal ROM are
written into the NVM (Nonvolatile Memory). When the power is turned on, required data for the current
picture, such as status memory data, etc., are selected, and they are written into the internal RAM.
When adjustment is carried out, adjustment data are written into the NVM automatically (items on the
user mode) or by the trigger of memory operation (items on the service mode and special service mode).
Adjustable items (W/B and Device Adjust) of the service mode and special service mode are memorized
into the NVM by the memory operation. At the same time, the factory preset (adjusted) data are all
eliminated from the memory.
3-8
2
C (Pins 24 and 28).
2 C to the MAIN CPU.
VPL-PX32