Diamond Systems 16-Channel 12-Bit Analog Output PC/104 Module Examples Single channel output

Examples

Single channel output

Assume channels 0 - 7 are configured for 0-5V. To set channel 0 to 3V, do the following: D/A code is 3V / 5V x 4096 = 2458 (value is rounded to nearest integer)

LSB = 2458 AND 255 = 154

MSB = (2458 AND 3840) / 256 = 9

Step 1. Write 154 to base + 0 (LSB register).

Step 2. Write 0 to base + 2 (Channel register).

Step 3. Write 9 to base + 1 (MSB register). The value 2458 is written to DAC 0. Step 4. Read from base + 0. DAC 0 now outputs 3.000V.

Two channel output

Assume channels 0 - 7 are configured for 0-5V. To set channel 0 to 3.8V and channel 3 to 1.5V, do the following:

D/A code for channel 0 = 3.8 / 5 x 4096 = 3113 LSB = 3113 AND 255 = 41

MSB = (3113 AND 3840) / 256 = 12

D/A code for channel 1 = 1.5 / 5 x 4096 = 1229 LSB = 1229 AND 255 = 205

MSB = (1229 AND 3840) / 256 = 4

Step 1. Write 41 to base + 0 (LSB register).

Step 2. Write 0 to base + 2 (Channel register).

Step 3. Write 12 to base + 1 (MSB register). The value 3113 is written to DAC 0. Step 4. Write 205 to base + 0 (LSB register).

Step 5. Write 0 to base + 2 (Channel register).

Step 6. Write 4 to base + 1 (MSB register). The value 1229 is written to DAC 1.

Step 7. Read from base + 0. DAC 0 and DAC3 are both updated to their new output voltages. All other channels remain at their existing output voltages.