www.diamondsystems.com DMM-32DX-AT User Manual Rev A.04 Page 2
DMM-32DX-AT 16-Bit Analog I/O PC/104 Module With Autocalibration
TABLE OF CONTENTS
1. DESCRIPTION ...................................................................................................................................................... 4
2. FEATURES ........................................................................................................................................................... 5
3. DMM-32DX-AT BOARD DRAWING ................................................................................................................... 6
4. I/O HEADERS PINOUT AND PIN DESCRIPTION ...................................................................................................... 7
4.1 Analog I/O Header – J3 ............................................................................................................................. 7
4.2 Digital I/O Header – J4 ............................................................................................................................. 8
4.3 Serial I/O Header – J11 ............................................................................................................................. 9
5. BOARD CONFIGURATION................................................................................................................................... 10
5.1 Base Address ............................................................................................................................................ 10
5.2 Interrupt level .......................................................................................................................................... 10
5.3 DMA level ................................................................................................................................................ 10
5.4 Single-Ended / Differential A/D Channels ............................................................................................... 11
5.5 D/A Configuration ................................................................................................................................... 12
5.6 Digital I/O Pull-Up / Pull-Down ............................................................................................................. 12
5.7 16-Bit Data Bus ....................................................................................................................................... 12
6. I/O REGISTER MAP ........................................................................................................................................... 13
6.1 I/O Map Description ................................................................................................................................ 13
6.2 I/O Map Reference – Write ...................................................................................................................... 14
I/O Map Reference – Read .................................................................................................................................. 15
6.3 I/O Map Details ....................................................................................................................................... 17
6.4 Page 0: 82C54 Counter/Timer Access ..................................................................................................... 25
6.5 Page 1: 82C55 Digital I/O Circuit .......................................................................................................... 26
6.6 Page 2: Expanded FIFO Control ............................................................................................................ 27
6.7 Page 3: Autocalibration Registers ........................................................................................................... 27
6.8 Page 4: dsPIC Interface .......................................................................................................................... 29
6.9 Page 5: D/A Waveform Generator .......................................................................................................... 31
6.10 Page 6: CPLD I/O Window ..................................................................................................................... 32
6.11 Page 7: D/A Output Channel Control ..................................................................................................... 32
7. ENABLING ENHANCED FEATURES ...................................................................................................................... 34
7.1 Enabling Enhanced Features (Enhanced Mode) ..................................................................................... 34
7.2 Disabling Enhanced Features (Normal Mode) ........................................................................................ 34
8. ANALOG INPUT RANGES AND RESOLUTION ....................................................................................................... 35
8.1 Unipolar and Bipolar Inputs ................................................................................................................... 35
8.2 Input Ranges and Resolution ................................................................................................................... 35
8.3 A/D Conversion Formulas ....................................................................................................................... 36
8.4 Correlation between A/D Code and Input Voltage .................................................................................. 36
9. PERFORMING AN A/D CONVERSION .................................................................................................................. 38
9.1 Select the input channel or input channel range ..................................................................................... 38
9.2 Select the analog input range .................................................................................................................. 39
9.3 Wait for the analog circuit to settle ......................................................................................................... 39
9.4 Start an A/D conversion on the current channel ..................................................................................... 39
9.5 Wait for the conversion to finish .............................................................................................................. 39
9.6 Read the A/D data .................................................................................................................................... 39
9.7 Convert the numerical data to a meaningful value .................................................................................. 39
10. A/D SAMPLING METHODS ............................................................................................................................ 40
10.1 Sampling Modes ...................................................................................................................................... 40
10.2 FIFO Description .................................................................................................................................... 41
10.3 Scan Sampling ......................................................................................................................................... 41
10.4 Sequential Sampling ................................................................................................................................ 41
11. HOW TO PERFORM A/D CONVERSIONS USING INTERRUPTS .......................................................................... 42
12. ANALOG OUTPUT RANGES AND RESOLUTION ............................................................................................... 43
12.1 Description .............................................................................................................................................. 43
12.2 Resolution ................................................................................................................................................ 43
12.3 Full-Scale Range Selection ...................................................................................................................... 43