![Johnson & Johnson DINAMAP Compact T Скачать руководство пользователя страница 24](http://html1.mh-extra.com/html/johnson-and-johnson/dinamap-compact-t/dinamap-compact-t_service-manual_2022992024.webp)
DINAMAP*
Compact
Vital Signs Monitor
24
life of the print head, a thermistor constantly measures the temperature of the head. The print head
thermistor is used by the timer circuit to reduce the width of the PRINTER_OE pulse as the system
heats up. The print head vVP is also employed to alter the width of the PRINTER_OE pulse.
A typical print trigger pulse width is 6 ms. An opto-transistor detects the presence of printer paper and
a micro switch detects the status of the printer door, open or closed. These two devices are combined
to produce the PRINTER_READY signal, which inhibits the printer action when clear and is sent back to
the PIC as PRINTER_BUSY. Data for printing is sent from the system processor to the printer board
via the SPI bus.
Because the instantaneous power demand of the printer is quite high, a dedicated 6.1 volt VP
is generated from VRAW by IC1 and extra reservoir capacity is provided by C16 and C17.