Download DM5604 / DM6604 User`s Manual

BA + 16: D/A Converter 7 LSB (Write Only) ................................................................................................ 4-7
BA + 17: D/A Converter 7 MSB (Write Only) ............................................................................................... 4-7
BA + 18: D/A Converter 8 LSB (Write Only) ................................................................................................ 4-7
BA + 19: D/A Converter 8 MSB (Write Only) ............................................................................................... 4-7
BA + 20: Update DAC Outputs (Write Only) ................................................................................................. 4-7
BA + 21: Reserved ........................................................................................................................................... 4-7
BA + 22: IRQ Enable (Write Only) ................................................................................................................. 4-7
BA + 23: Interrupt Status/Clear (Read/Write) ................................................................................................ 4-7
Programming the DM5604 .................................................................................................................................... 4-8
Clearing and Setting Bits in a Port ................................................................................................................... 4-9
D/A Conversions ............................................................................................................................................. 4-10
Initializing the 8255 PPI ................................................................................................................................. 4-11
Digital I/O Operations ..................................................................................................................................... 4-11
Interrupts .......................................................................................................................................................... 4-12
What Is an Interrupt? .................................................................................................................................. 4-12
Interrupt Request Lines ............................................................................................................................... 4-12
8259 Programmable Interrupt Controller ................................................................................................... 4-12
Interrupt Mask Register (IMR) ................................................................................................................... 4-12
End-of-Interrupt (EOI) Command .............................................................................................................. 4-12
What Exactly Happens When an Interrupt Occurs? .................................................................................. 4-12
Using Interrupts in Your Programs ............................................................................................................. 4-13
Writing an Interrupt Service Routine (ISR) ............................................................................................... 4-13
Saving the Startup Interrupt Mask Register (IMR) and Interrupt Vector .................................................. 4-14
Restoring the Startup IMR and Interrupt Vector ........................................................................................ 4-15
Common Interrupt Mistakes ....................................................................................................................... 4-15
Example Programs ............................................................................................................................................... 4-15
C Programs ...................................................................................................................................................... 4-15
BASIC Programs ............................................................................................................................................. 4-15
CHAPTER 5 — CALIBRATION......................................................................................................... 5-1
Required Equipment .............................................................................................................................................. 5-3
D/A Calibration — X2 Voltage Multiplier ........................................................................................................... 5-3
APPENDIX A — DM5604 SPECIFICATIONS .................................................................................. A-1
APPENDIX B — P2 CONNECTOR PIN ASSIGNMENTS .............................................................. B-1
APPENDIX C — COMPONENT DATA SHEETS ............................................................................ C-1
APPENDIX D — WARRANTY ........................................................................................................... D-1
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