Instruction manual

PC24E/25E
Page 18
3. Write a value to all DACs.
4. Output a Sine wave to one DAC.
5. Output a Sine wave to all DACs.
6. Exit.
Option 1 need only be chosen if a base address other than the factory set 300 hex has been
set up on the board.
Enter a number 2 to 4 to choose the required output(s) and follow the on-screen instructions.
Note: All values are input as decimal numbers, which can take any value from 0 to 4095.
4.3 Input/Output Address Space used by the PC24E/PC25E
When writing application software for the PC24E/25E, the programmer will need to know the
location of all DAC and Timer registers in the I/O space. These locations are given in figure 10
below, showing each register as an offset from the base address set up on the board. For
example, if the base address is set at 300 hex, then the 82C53 control register is at 30B hex.
NOTE Selection of the order in which the MSB and LSB are loaded into the DACs ( jumpers
J6 - 9 ) has no effect on the register addresses.
Address Function
BA + 00 DAC1 (lo byte)
BA + 01 DAC1 (hi byte)
BA + 02 DAC2 (lo byte)
BA + 03 DAC2 (hi byte)
BA + 04 DAC3 (lo byte)
BA + 05 DAC3 (hi byte)
BA + 06 DAC4 (lo byte)
BA + 07 DAC4 (hi byte)
BA + 08 82C53 Counter/Timer 0
BA + 09 82C53 Counter/Timer 1
BA + 0A 82C53 Counter/Timer 2
BA + 0B 82C53 Control Register
Figure 10 INPUT/OUTPUT ADDRESS SPACE
Notes to figure 10:
1. BA = Base Address as set on SW1.
2. Register address is Base Address plus offset.
3. Offset to be added to the BA is stated as a Hex value.