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Glossary Electronics D D Codes D01: Light on for next move. D02: Light off for next move. D03: Flash (Light On, Light Off) after move (effect is limited to block in which appears, i.e. non-modal). You can also think of a D03 as D02, D01, D02 series of commands linked together. D codes with values of 10 or greater represent the aperture's position on the list or wheel. It is very important to understand that there is no universal "D10" or "D30". Unlike the D01 , D02, and D03 counterparts which have a fixed meaning (draw, move, flash), D10 and higher values have aperture shapes and dimensions assigned to them by each individual user. Hence, one job's D10 could be a 10 mil Round, when another job's D10 could be a 45 mil Square. There are two distinct ways to number an aperture list. The traditional 24 aperture system started with D10 - D19, jumping suddenly to D70 - D71, then back to D20 - D29, ending with D72 -D73. This is still a common format for output for CAD packages, and is still mandatory for old 24 aperture Gerber vector Photoplotters. It is now common to start with D10, then increase numerically in steps of 1 (D10, D11, etc.) continuing up to D70 and beyond, rarely beyond 1000 individual apertures. D/A:
Digital to Analog Converter Data Formats Note: At present Circuit Graphics is not able to make use of DXF files. Please supply board outline details in Gerber format. DMA:
Direct Memory Access Additional features of the DMA include up to seven independent channels, up to 8 transfer sources, byte or word transfer capability, block or loop transfers, programmable bus bandwidth, CPU interrupt capability on transfer completion, and memory stretch capability for addresses beyond the 64 Kbyte internal memory map. Drill Data Along with the drill file we require a report file which provides the finished hole size and total hole count for each tool change. Any non-plate through holes (NPTH) should also be clearly identified. The report file may be supplied as a separate ASCII text file or may be included as part of your Read_me.txt file. DTMF:
Dual-Tone Multi-Frequency
Electrically Erasable Programmable Read
Only Memory (EEPROM) and Erasable Programmable Read Only Memory (EPROM) are both
types of ROM that can be programmed by the user. EPROM can be erased by exposing
it to ultraviolet light, whereas EEPROM can be erased electrically (i.e., in the
application). Once erased, EPROMs and EEPROMs may be reprogrammed with new
instructions and data. EEPROM and EPROM information is non-volatile in that it
does not change when power is removed. 1-800-319-3599E-Mail: info@pcbdesignandfab.com |