Rainbow Electronics DS2152 - Manual (Page 53)

DS2152
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be selected via the IBCC register. The DS2152 will
detect repeating pattern codes in both framed and
unframed circumstances with bit error rates as high as
10**–2. The code detector has a nominal integration
period of 48 ms. Hence, after about 48 ms of receiving
either code, the proper status bit (RUP at SR1.7 and RDN at SR1.6) will be set to a one. Normally codes are
sent for a period of 5 seconds. it is recommend that the
software poll the DS2152 every 100 ms to 1000 ms until
5 seconds has elapsed to insure that the code is contin-
uously present.
IBCC: IN–BAND CODE CONTROL REGISTER (Address=12 Hex)
(MSB) (LSB)
TC1 TC0 RUP2 RUP1 RUP0 RDN2 RDN1 RDN0
SYMBOL POSITION NAME AND DESCRIPTION
TC1 IBCC.7 Transmit Code Length Definition Bit 1. See Table 12–1
TC0 IBCC.6 Transmit Code Length Definition Bit 0. See Table 12–1
RUP2 IBCC.5 Receive Up Code Length Definition Bit 2. See Table 12–2
RUP1 IBCC.4 Receive Up Code Length Definition Bit 1. See Table 12–2
RUP0 IBCC.3 Receive Up Code Length Definition Bit 0. See Table 12–2
RDN2 IBCC.2 Receive Down Code Length Definition Bit 2. See Table 12–2
RDN1 IBCC.1 Receive Down Code Length Definition Bit 1. See Table 12–2
RDN0 IBCC.0 Receive Down Code Length Definition Bit 0. See Table 12–2
TRANSMIT CODE LENGTH Table 12–1
TC1 TC0 LENGTH SELECTED
0 0 5 bits
0 1 6 bits / 3 bits
1 0 7 bits
1 1 8 bits / 4 bits / 2 bits / 1 bits
RECEIVE CODE LENGTH Table 12–2
RUP2/
RDN2
RUP1/
RDN1
RUP0/
RDN0
LENGTH
SELECTED
0 0 0 1 bits
0 0 1 2 bits
0 1 0 3 bits
0 1 1 4 bits
1 0 0 5 bits
1 0 1 6 bits
1 1 0 7 bits
1 1 1 8 bits
TCD: TRANSMIT CODE DCEFINITION REGISTER (Address=13 Hex)
(MSB) (LSB)
C7 C6 C5 C4 C3 C2 C1 C0
SYMBOL POSITION NAME AND DESCRIPTION
C7 TCD.7 Transmit Code Definition Bit 7. First bit of the repeating pattern.
C6 TCD.6 Transmit Code Definition Bit 6.