ANT S19 - 6. Phenomenon: PT2 Serial Port Stops During Test; 7. Phenomenon: PT1 OK, PT2 Reports Chip NG; VI. Control Board Problems Causing Malfunctions; 1. Whole Machine Does Not Operate

S19 Maintenance Guide
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6. Phenomenon: Check that chip test is OK, PT2 function test serial port does not stop (long-distance running)
Repair method: during the PT2 test, watch the serial port print log. When the serial port starts to operate for a long time, use a short-circuit
probe to short-circuit RO&1.8V. The short-circuit starts from the first chip. If the serial port stops long-tem operating after the short circuit,
the first chip is OK. According to this method, find the chip that still has the long-tem operating failure after a certain chip is short-
circuited. Generally, it is caused by a certain chip damaging, so just replace it;
Figure 5-19
7. Phenomenon: PT1 chip test is OK, PT2 function test always reports a certain chip NG;
Repair method: check the appearance, measure the chip capacitor or resistance in front, usually it's caused by poor chip soldering or a chip
capacitor, resistor damaging or abnormal resistance;
VI. Control board problem causing the following problems
1. The whole machine does not operate
1) Check whether the voltages at several voltage output points are normal. U8 can be disconnected first if 3.3V is short-circuited. If it is
still short-circuited, the CPU can be unplugged for measurement. For other voltage abnormalities, generally replace the corresponding
converter IC.
2) If the voltage is normal, please check the welding status of the DDR/CPU
3) Try to update the flash program with SD card;
If the control board card recovery machine needs to start normally, the following two steps are required:
a) After the card recovery is successfully, the green LED indicator will be always on, and the power shall be turned off and restarted;
b) Wait for 30s after powering on again (the time course of turning on OTP)
c) OTP (One Time Programable) is a memory type of MCU, which means one-time programmable: after the program is programmed into
the IC, it cannot be changed and cleared again;
Precautions:
(1) Sudden power failure during OTP or time of less than 30s will cause the control board to fail to open the OTP function. As for the issue
that the control board cannot start (not networked), the user needs to replace the U1 (main control IC FBGA of control board). U1 can no
longer be used in 19 series after replacement
(2) For the control board with OTP function turned on, U1 cannot be used on other series of models;