28128 Parallax Inc, 28128 Datasheet - Page 59

• Manufacturer Part Number: 28128
• Description: KIT BASIC ANALOG/DIGI PARTS ONLY
• Manufacturer: Parallax Inc

Specifications of 28128

• Accessory Type: ADC, DAC
• Product: Microcontroller Accessories
• For Use With/related Products: BASIC Stamp® 2 and Board of Education
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The subroutine
ADC0831. This subroutine is where the usefulness of the
on the BASIC Stamp is connected to the /CS pin on the ADC0831. Likewise, pins P1 and
P2 are connected to CLK and D0. When sending signals to the /CS pin, we can enter a
command like
and it makes deciphering the code easier too. It's also easier to change one definition in
the top of the program should you decide to connect the ADC0831 to a different BASIC
Stamp I/O pin
The command
conversion, we need to send a high signal (5 volts). Then we need to send a low signal (0
volts) to the /CS input on the ADC0831 using
/CS input needs to stay low for the duration of the conversion.
The
this command guarantees that the next command (
has the right shape, low-high-low. Sending high and low signals using the
commands is an alternative to the
experiment.
LOW CLK
DO
LOOP
ADCDATA:
RETURN
ADC_Data:
GOSUB ADCDATA
GOSUB CALC_VOLTS
GOSUB DISPLAY
HIGH CS
LOW CS
LOW CLK
PULSOUT CLK, 210
SHIFTIN dataOutput,CLK,MSBPOST,[adcbits\8]
HIGH CS
LOW CS
command is necessary so that the clock pulses take the right form. Using
HIGH CS
HIGH CS
ADC_Data
instead of
sends a high signal to the ADC0831’s /CS pin. To start a
sends control signals to and collects output data from the
HIGH 0
OUT0=1
. It makes more sense when writing the code,
LOW CS
and
PULSOUT
OUT0=0
. The signal sent to the ADC0831's
PIN
) will send a clock pulse that
techniques used in the first
Figure 3-5
Flow Diagram
A subroutine sends the
program to the specified
label. In this case the label
is ADC_DATA. Then the
program continues executing
commands until it
encounters the return
command. The return
command sends the
program back to the
command immediately after
the GOSUB command. In this
case it's another GOSUB
command.
directive really shows. P0
HIGH
and
LOW