II- 16
2.3.8 Reset
Circuit
When power is supplied from the power supply PCB, +3.3V is supplied, and power is supplied to
the CPU. At this point, if +3.3V voltage line goes over +2.8V, the reset circuit (U5) sets High to the
RESET input (14 pins) of the CPU, clearing the RESET status of the CPU.
If the +3.3V voltage line drop to +2.8V or lower due to any reason during operation, the reset
circuits returns Low signal to the CPU and the CPU goes to the RESET status.
Fig. 2.3-10 Reset Circuit
2.3.9
USB Interface Circuit
The CPU of QL-570 is connected with a PC using the USB cable via U6 and CN12.
U6 and CPU (U7) establishes bus connection with 8-bits.
Fig. 2.3-11 USB Interface Circuit
Summary of Contents for QL 570 - P-Touch B/W Direct Thermal Printer
Page 1: ...P touch SERVICE MANUAL MODEL QL 570 ...
Page 29: ...III 4 Grease to be used Silicon grease G501 rice grain sized Platen gear Double gear C ...
Page 84: ...IV 6 4 5 TROUBLESHOOTING FLOWS 1 Printing is performed with specific dots omitted ...
Page 85: ...IV 7 2 The tape is not detected correctly ...
Page 86: ...IV 8 3 LED does not turn on ...
Page 87: ...IV 9 4 No printing is performed 5 The interface malfunction ...
Page 88: ...IV 10 6 The tape is not cut ...
Page 89: ...IV 11 7 The tape is not fed correctly ...
Page 122: ...Sep 2007 SM PT002 3 ...