Remote-processing RPC-2350 Uživatelský manuál stáhnout pdf (Strana 24)

CHAPTER 4 SERIAL PORTS

4-5

is empty.

In this mode, you have access to the full 256 bytes.

If you don' t read the buffer an d the buffer fills, all

subsequent characters are discarded. INKEY$(n)

may be used anywhere in the program.

3. COM$(n) retrieves all characters in the buffer,

including < cr> ' s and other control codes. This

function is commonly used with ON COM$

multitasking statement. You can retrieve 128 of the

256 bytes in the serial buffer at one time.

DISABLING PROGRAM BREAK

Program execution can be interrupted by pressing the

< Esc> key. To disable this recognition so the program

does not terminate, put the following command in your

program:

1000 CONFIG BREAK port,1

Where port is 1 (J1) or 2 (J4 or P3).

SPI PORT

A software SPI port is provided at J11. SPI (Serial

Peripheral Interface) is used to communicate with a

number of IC’s. These include D /A’s, A/D ’s, U ART’s,

and other devices. J11 provides two chip selects.

The optional touch screen interface uses SPI port 1.

The SPI function is used to read and write data.

Unfor tunately, SPI has a v ariety of da ta formats. D ata

to send and receive from a device can be anywhere from

8 to 24 bits. The clock polarity an d data phase c an idle

high or low when data is latched.

CAM BASIC SPI function supports the following form at:

Clock idle polarity: low

Clock-data phase: low

This format supports the Maxim MAX186/188 and Burr-

Brown ADS7843 IC’s. The program SPIDEMO1.BAS

uses the MAX186/188 to return the result of an A/D

calculation. Functionally, it is the same as the AIN

command.

If your form at needs are different, ther e is a

CAMBASIC program (SPIDE MO2. BAS) that you can

use as a basis to read and write to other SPI devices.

Comm and format is:

a = SPI(channel,out_length,data, delay,in_length)

Where:

channel = 0 to 2, the SPI channel number.

out_length = 0 to 16, data output length in bits.

When zero, no data is shifted out. data can be any

value but must be included.

data = 0 to 65,535, command/data to send to SPI

device.

delay = time to wait before retrieving information

from SPI port. Time in micro-seconds is calculated

as follows: time = delay * 1.1 + 4. If 0 , there is

no delay. Use 0 if there is no data to retrieve (i.e.

sending to D/A).

in_length = 0 to 16, data input length in bits. W ill

return a number from 0 to 65535.

The table below shows the location of SPI device selects.

A device is selected when a line goes low.

SPI port number Location

0 Analog input (U10)

1 J11-4

2 J11-5

1 2 ... 19 20 21 22 23 24 25 26 27 28 29 ... 82 83

Komentáře k této Příručce

Žádné komentáře

Remote-processing RPC-2350 Uživatelský manuál Strana 24

Komentáře k této Příručce

Související produkty a manuály pro Počítače Remote-processing RPC-2350