VeriFone e265, Руководство пользователя и передовые методы использования

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A
RCHITECTURE
iap_get_keypad_state()
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E
355/
E
265 U
SER AND
B
EST
P
RACTICES
G
UIDE
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Message-based protocol allows for CRC verification of each message.
•
Maximum message size is 2048 bytes (2040 bytes for payload).
•
Applications can write any size data, but must verify the number of bytes
written and repeat write until total number of bytes written.
Table 9 presents the PMR-MUX2 protocol commands.
Table 9 PMR-MUX2 Protocol Commands
Command String
Command
Name
Description
<0xFF 0x5A>o<num><crc> Open Channel This command opens the channel number specified by the
<num>
parameter. The command character is a 1 byte
lower case letter ‘o’. The
<num>
parameter is a one byte
ASCII number from 2 to 6 to specify which channel to
open. This is sent when the smart device opens a channel.
The
<crc>
field is a 16 bit CRC of the complete message
including the 2 byte header and the command message
data.
<0xFF 0x5A>c<num><crc> Close Channel This command is sent by the smart device to close a given
channel. The command character is a 1 byte lower case
letter ‘c’. The
<num>
parameter is a 1 byte ASCII number
from 2 to 6 to specify the channel number. The
<crc>
field
is a 16 bit CRC of the complete message including the 2
byte header and the command message data.
Command:
<0xFF><0x5A>i<crc>
Response:
<0xFF><0x5A>i<Length><crc>
MTU Query Query for Maximum Transmission Unit (MTU) which is
used to indicate the maximum message frame length for
mux protocol. The command character is a 1 byte lower
case letter ‘i’. This should be used by all smart devices
using this protocol in case of buffer length changes in the
future. This returned length includes both the message
header, body and CRC. The length is 4 byte ASCII Hex.
The
<crc>
field is a 16 bit CRC of the complete message
including the 2 byte header and the command message
data.
<0xFF><0x5A>d<num>
<length><data><crc>
Channel data
message
This command sends/receives a data message to/from a
selected channel. The command character is a 1 byte
lower case letter ‘d’. The
<num>
parameter is 1 byte ASCII
number from 2 to 6 to specify the channel number.
Channel number of XPI is 2, barcode 3, Zontalk 4, control
5, and debug 6. The
<length>
is a 4 byte ASCI Hex
string from 0000-MTU length in “I” command. The
<crc>
field is a 16 bit CRC of the complete message including
the 2 byte header and the data field.