USB-DAQ-SS Flexipanel, USB-DAQ-SS Datasheet - Page 7

• Manufacturer Part Number: USB-DAQ-SS
• Description: IC SYSTEM DATA LOGGER 20-SSOP
• Manufacturer: Flexipanel

Specifications of USB-DAQ-SS

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 658-1042-5

Interrupt Processing
In addition to being triggered by the real time clock,
application code can be executed in response to an
interrupt event. Most interrupts are supported. Interrupt
priority should be set to high.
When an interrupt occurs, USB-DAQ will clear the
interrupt enable bit and pass control to the application
code. It is then the application code’s responsibility to
clear the interrupt flag and re-set the interrupt enable.
File Access
Up to four files can be accessed by the USB-DAQ. It
modifies the contents of these files but does not create
or delete them, or modify their length. They must be
copied from the PC for the application to execute.
When the end of the file is reached, the file pointer
wraps round to the beginning again (plus any header
space reserved.) All read and write operations must be
within the 512-byte sector boundaries of the files.
Therefore it is usual for logged records to be a power of
two in length.
Compiled Code
The code is compiled into a reduced instruction set
which is then interpreted at run-time.
code is shown in the spreadsheet.
TEAclipper Programming
For programming the firmware using TEAclipper/PIC HV,
the PGC, PGD and Vpp pins must be accessible.
During programming, these pins must be protected
against contention.
subject to up to 13V during programming. Nothing else
should be connected to Vpp except via a 22k pull-up
resistor.
The TEAclipper connector format is shown in figure 8.
Since
programming socket is required. The TEAclipper can be
‘leaned’ against the plate-through holes shown.
It is strongly recommended that this connector is
included in circuits even if in-circuit programming is not
anticipated, since this allows you to upgrade the
firmware if necessary.
Evaluation Board
The USB-Eval evaluation board is available for
evaluating USB-DAQ. Due to the variety of potential
implementations it is supplied unpopulated and a
prototyping area is provided. This will be necessary for
SD memory implementation (see Figure 9).
p7 of 8
Pin 1 indicated
by square pad
Figure 8. Recommended plate-through connector design
the
programming
26-Aug-10
In particular, note that Vpp is
time
2.54mm spacing
is
very
This compiled
1mm hole dia
USB-DAQ
fast,
no
It is recommended that new users work with internal
memory to reduce the number of connections required
and then migrate it to test the circuit actually required.
Start, perhaps, with Figure 3 plus the
Note
development:
It is strongly recommended that an Escape pin is used,
since without it the USB-DAQ chip can be rendered
unusable.
Code Examples
The following examples are provided in the development
kit to illustrate USB-DAQ usage.
DigitalAnalog.xls
This example logs the time, the analog pins AN1 and
AN0, and digital pin RA2 every three seconds. RA4 is
used to power the sensor, and so illustrates how to set
an output high our low.
Interrupts.xls
This file shows how interrupts are handled. It sets up a
falling-edge interrupt on INT2. When an interrupt occurs,
it flashes an LED on RA5 and logs the time to the file.
The interrupt flag is then re-enabled and USB-DAQ
goes back to sleep.
AnniLogic.xls
This anniversary reminder application demonstrates
basic arithmetic and how to read files. It also illustrates:
- How long file names can be presented to the user
- The use of the preprocessor to create meaningful
- Calling subroutines.
1.
2.
while USB-DAQ accesses them using their short file
names.
variable names, and overlaying them to re-use
memory.
the
Forgetting to press the ‘Compile Now’ button
before copying the CONFIG.DAT to USB-DAQ.
SD memory needs 3.3V power regulation.
HW147-5
Figure 9. Evaluation board example
following
common
mistakes
32768Hz
www.hexwax.com
oscillator.
during