ViewSonic VA702B Service Manual - Page 35

D-SUB D-SUB 15PIN 15PIN RS232 9PIN 7. Upload firmware to MCU via VGA Cable 7.1 Connect ISP board between monitor and PC as below configure Insert to RS232 9pin CON on PC ISP Board Service cable LCD Monitor D-Sub PC VGA output +12V Adapter Normal shipping cable 7.2 Before plug in the power cord, make sure keep "▲" key to be pressed, when power on you can enter ISP mode. 7.3 8051ispwriter.exe will detect automatically which MCU used in this monitor. Do it as the order shown on the screen, choose the corresponding firmware version, and load to MCU. 7.4 After finish, please plug out power cable and re-start monitor again. 8 After repair, to ensure the quality you should do the following test and adjustment Item Test OSD function Contrast Check Content 1.Signal is set as 1280x1024@60Hz 2. LCM button are from left to right, checking whether each single function key and compound function key can be worked. 1. Set input mode to 1280x1024@60Hz 2. Set Pattern to 32 gray shades 3. Set contrast to the max. The brightest 5~6 shades brightness cannot be distinguished. Color Temperature 1. Do "Auto color" at 1280 x 1024@60Hz, 32gray shades 2. Measure color temperature, check it complies with the following temperature: 5400K x=0.335 +/- 0.02, y=0.350 +/- 0.02 6500K x=0.313 +/- 0.02, y=0.329 +/- 0.02 9300K x=0.283 +/- 0.02, y=0.298 +/- 0.02 Modes switching check 1. Use Chroma Pattern Generator to make sequence. VESA (640x480 800x600 1024x768 1280x1024), MAC 832x624 DOS (640x350 720x400), the detail supported modes and power saving signal. 2. Confirm the above timing modes must be full screen and the picture must be normal. 3. LED is Orange at power saving mode. Equipment Chroma Signal Generator Chroma Signal Generator Chroma Signal Generator and color analyzer Chroma Signal Generator ViewSonic Corporation Confidential - Do Not Copy 32 VA702-1_VA702b-1