rtd DM6210, User Manual

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BA + 10: 8254 Timer/Counter 2 (Read/Write 8-bit) ....................................................................................4-6
BA + 11: 8254 Control Word (Write Only 8-bit) .........................................................................................4-6
BA + 12: Digital I/O Port 0 (Read/Write 8-bit) ............................................................................................4-7
BA + 13: Digital I/O Port 1 (Read/Write 8-bit) ............................................................................................4-7
BA + 14: Digital I/O Strobe Select (Read/Write 8-bit) ................................................................................4-7
BA + 15: Digital I/O Control (Read/Write 8-bit) ..........................................................................................4-8
Programming the DM6210 ..................................................................................................................................4-9
Clearing and Setting Bits in a Port ..................................................................................................................4-9
CHAPTER 5 — A/D CONVERSIONS ................................................................................................. 5-1
Selecting a Channel ..........................................................................................................................................5-3
Starting an A/D Conversion ............................................................................................................................5-3
Monitoring Conversion Status ........................................................................................................................5-3
Reading the Converted Data ...........................................................................................................................5-4
Channel Scanning ............................................................................................................................................5-5
CHAPTER 6 — INTERRUPTS ............................................................................................................ 6-1
Software Selectable Interrupt Sources ...........................................................................................................6-3
Software Selectable Interrupt Channel ...........................................................................................................6-3
Basic Programming For Interrupt Handling ..................................................................................................6-4
What Is an Interrupt? ...................................................................................................................................6-4
Interrupt Request Lines ...............................................................................................................................6-4
8259 Programmable Interrupt Controller ..................................................................................................6-4
Interrupt Mask Register (IMR) ...................................................................................................................6-4
End-of-Interrupt (EOI) Command ..............................................................................................................6-5
What Exactly Happens When an Interrupt Occurs? ................................................................................. 6-5
Using Interrupts in Your Programs ............................................................................................................6-5
Writing an Interrupt Service Routine (ISR) ...............................................................................................6-5
Saving the Startup Interrupt Mask Register (IMR) and Interrupt Vector ...............................................6-6
Restoring the Startup IMR and Interrupt Vector .......................................................................................6-7
Common Interrupt Mistakes .......................................................................................................................6-7
CHAPTER 7 — TIMER / COUNTERS ............................................................................................... 7-1
CHAPTER 8 — DIGITAL I/O .............................................................................................................. 8-1
BA + 12: Digital I/O Port 0 (Read/Write 8-bit) .................................................................................................8-3
BA + 13: Digital I/O Port 1 (Read/Write 8-bit) .................................................................................................8-3
BA + 14: Digital I/O Strobe Select (Read/Write 8-bit).....................................................................................8-3
BA + 15: Digital I/O Control (Read/Write 8-bit) ..............................................................................................8-4
Strobing Data into Port 0 or Port 1 ......................................................................................................................8-4
CHAPTER 9 — EXAMPLE PROGRAMS .......................................................................................... 9-1
C Programs ............................................................................................................................................................9-3
Quick Basic Programs ..........................................................................................................................................9-3
CHAPTER 10 — CALIBRATION...................................................................................................... 10-1
Required Equipment .......................................................................................................................................... 10-3
A/D Calibration .................................................................................................................................................. 10-4
Unipolar Calibration ..................................................................................................................................... 10-5
Bipolar Calibration........................................................................................................................................ 10-5