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cross mob
Level 1
Level 1
5 sign-ins First question asked Welcome!

I opened up the head unit from our vehicle and realised I could turn the screen into a very versatile little monitor. The reason for its retirement was because the touch screen stopped working… You can ask at the Automotive shops that do installations or the Wreckers for your own head units, the LCD can still be good even if the touchscreen glass was cracked (use an inferior MCU to run it instead and have a spare Cypress chip). Mine is the LSP2GTS (a.k.a. Anatel 52098606), it has only two video inputs, one split to go to both chips (termination resistor halved).


Chip list includes:

AU1340 Micropr (with two 1Gbit RAM W971GG6JB, 32G flash JW983 and 64Mbit s29gl064n90) 

TW8816 flat panel processor (with 800x480 LB070WV1-TD05; five inputs)

TW9900 video decoder (four more inputs)

CY8C21334-24PVXA touch sensing microprocessor

SAF7741HV audio DSP (TEF7000HN one radio tuner; fourteen inputs (see fig 2, 31))

70F3351GC(A)SG3 microprocessor (near DSP) no idea, sound synthesis?

RBFA C211C Bluetooth


I was entertaining thoughts of using a PIC 12C508 (or something reusable) and emulate I2C to activate the TW8816's OSD and program to show the Composite, S-Video, Component (analogue and digital), and RGB (analogue and digital) inputs (and read their configuration)- until I saw what the touchscreen was controlled with. Likely the Cypress failed due to extensive environmental heating (poorly positioned), I am not sure if the OEM's (it is LG and Holden(General Motors) branded) code can be extracted🖊️ and fixed, if so can add my stuff around it, and send touches to my code. The OSD programming won't take much room even if I do a good job at it (and i could add extracurricular activities in the OSD interface, like forwarding I²C commands and MCU pin commanding, could port some 16 colour games to show on the OSD). The AU1340 could be lost technology so not bothering with that (there is an 8bit XIP MCU in the TW as well). I wasn't going to bother with the DSP, twice the codeing. I see you would you start accessing the chip using MiniProg1, MiniProg3 or ICE-Cube. Is it possible to use another microcontroller instead just like you can use PICs to program PICs🖊️? I have never done microprocessors before (since circuits can blink LEDs cheaper), I am happy with assembly but so far Cypress downloading is difficult (maybe they dislike Android, and their staff don't do website troubles).

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