CC-2401K2A-CS5 Copeland Communications Inc, CC-2401K2A-CS5 Datasheet - Page 15

• Manufacturer Part Number: CC-2401K2A-CS5
• Description: MODEM 2400BAUD SECURE 5V
• Manufacturer: Copeland Communications Inc

Specifications of CC-2401K2A-CS5

• Data Format: V.21, V.22, V.23, Bell 103
• Baud Rates: 2.4k
• Interface: UART
• Voltage - Supply: 4.2 V ~ 7 V
• Mounting Type: Surface Mount
• Package / Case: Module
• For Use With: 539-1002 - KIT EVALUATION WORLD MODEM II
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 539-1009; CC-2401K2A-CS5

© 2007, Copeland Communications, Inc.
2.
3.
4.
The method for receiving HDLC frames follows:
1.
2.
3.
When receiving HDLC frames, the host begins receiving data asynchronously from the CC-2401. When each
byte is received, the host should check the EOFR pin (or the ninth data bit). If the EOFR pin (or ninth data bit)
is low, the data is valid frame data. If the EOFR pin (or ninth bit) is high, the data is a frame result word.
Fast Connect
In modem applications that require fast connection times, it is possible to reduce the length of the handshake.
Additional modem handshaking control can be adjusted through the registers shown in the following table.
These registers are most useful if the user has control of both the originating and answering modems. When
the fast connect settings are used, there may be unintended data received initially. The host must tolerate
these bytes.
When the frame is complete, the host should simply stop sending data to the CC-2401. Since the CC-
2401 does not yet recognize the end of frame, it expects an extra byte and asserts CTS. If CTS is used to
cause a host interrupt, this final interrupt should be ignored by the host.
When the CC-2401 is ready to send the next byte, if it has not yet received any data from the host, it
recognizes this as an end of frame, raises CTS, calculates the final CRC code, transmits the code and
begins transmitting stop flags.
After transmitting the first stop flag, the CC-2401 lowers CTS indicating that it is ready to receive the next
frame from the host. At this point, the process begins again at step 1.
After the call is connected, the CC-2401 searches for flag data. Once the first non flag word is detected,
the CRC is continuously computed and the data is sent across the UART to the host after removing the
HDLC zero-bit insertion. The DTE rate of the host must be at least as high as that of data transmission.
HDLC mode only works with 8 bit data words; the ninth bit is used only for escape on TXD and end of
frame received (EOFR) on RXD.
When the CC-2401 detects the stop flag, it sends the last data word in the frame as well as the two CRC
bytes and determine if the CRC checksum matches. Thus, the last two bytes are not frame data but are
the CRC bytes, which can be discarded by the host. If the checksum matches, the CC-2401 sends “G”
(good). If the checksum does not match, the CC-2401 sends “e” (error). In addition, if the CC-2401
detects an abort (seven or more contiguous ones), it sends an “A”. When the “G”, “e”, or “A” (referred to
as a frame result word) is sent, the CC-2401 raises the EOFR (end of frame receive) pin. The GPIO1 pin
must be configured as EOFR by setting SE4[3](GPE) = 1. In addition to using the EOFR pin to indicate
that the byte is a frame result word, if in 9 bit data mode, (set S15[0] (NBE) = 1), the ninth bit is raised if
the byte is a frame result word. To program this mode, set S0C[3] (9BF) = 1 and SE0[3] (ND) = 1.
When the next frame of data is detected, EOFR is lowered and the process repeats with step 1.
Register
S1E
S1F
S20
S21
S22
S23
S24
S34
S35
Name
TSOD
VDDH
RSOL
ATTD
TSOL
VDDL
TATL
TASL
UNL
Function
Transmit Answer Tone Length
Answer Ton to Transmit Delay
Unscrambled Ones Length-V.22
Transmit Scrambled Ones Delay – V.22
Transmit Scrambled Ones Length – V.22
V.22/22b Data Delay Low
V.22/22b Data Delay High
Answer Tone Length
(only used in S1E[TATL] = 0x00)
Receive V.22 Scrambled Ones Length
Page 15 of 66
Data Sheet
(256) 5/3 ms
CC-2401K2 Datasheet Rev 1.5
53.3 ms
5/3 ms
5/3 ms
5/3 ms
5/3 ms
5/3 ms
5/3 ms
Units
1 s
CC-2401K2
Default
0xCB
0x2D
0x5D
0xA2
0xA2
0x03
0x09
0x08
0x5A
Connect
Fast
00
00
00
00
00
00
00
F0
00