參數(shù)資料
型號(hào): T7121-PL2
英文描述: T7121 HDLC Interface for ISDN
中文描述: T7121的HDLC接口用于ISDN
文件頁(yè)數(shù): 16/68頁(yè)
文件大?。?/td> 685K
代理商: T7121-PL2
16
Lucent Technologies Inc.
Data Sheet
April 1997
T7121 HDLC Interface for ISDN (HIFI-64)
Functional Description
(continued)
Bit Masking
When in the TDM highway mode (HWYEN, R0—B7 = 1), the HIFI-64 can be programmed to mask any combina-
tion of bits in a byte. As an example, this feature is used to process 16 kbits/s D-channel data where only 2 bits in
each byte are looked at when receiving, and where only 2 bits are transmitted during an 8-bit time slot. Using this
option, the HIFI-64 is able to support effective intermediate data rates of 8, 16, 24, 32, 40, 48, and 56 kbits/s.
The receiver ignores bit positions that are masked (cleared to 0) in the receiver bit mask register (R12). The trans-
mitter outputs high impedance (3-state) during the bit times specified (cleared to 0) in the transmitter bit mask reg-
ister (R13). The user can program any combination of bits to be masked in the receiver and transmitter
independently.
Upon chip reset, the default is as follows:
1. The receiver defaults to recognize all incoming data as valid (i.e., no masking).
2. The transmitter defaults to a state where all bits are masked.
The user must unmask the bits to be transmitted. This eliminates the problem of the HIFI-64 transmitting before the
time slot has been programmed in registers 7, 9, and 10.
Figures 8 and 9 show how 16 kbits/s operation is achieved by using the bit-masking option.
相關(guān)PDF資料
PDF描述
T7121 HDLC Interface for ISDN (HIFI-64)(應(yīng)用于ISDN的HDLC(高階數(shù)據(jù)鏈路)接口)
T7502 T7502 Dual PCM Codec with Filters
T7503 T7503 Dual PCM Codec with Filters
T7504 T7504 and T75504 Quad PCM Codecs with Filters
T7507 T7507 Quad PCM Codec with Filters, Termination Impedance, and Hybrid Balance
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
T7122 制造商:未知廠家 制造商全稱(chēng):未知廠家 功能描述:TRIANGULAR TYPE
T7-122A1 功能描述:撥動(dòng)開(kāi)關(guān) ON NONE OFF 1 Pole Low-Level Bat Handle RoHS:否 制造商:OTTO 觸點(diǎn)形式: 開(kāi)關(guān)功能: 電流額定值: 電壓額定值 AC: 電壓額定值 DC: 功率額定值: 端接類(lèi)型: 安裝風(fēng)格: 端子密封: 觸點(diǎn)電鍍: 照明:
T7-122B1 功能描述:撥動(dòng)開(kāi)關(guān) ON NONE ON 1 Pole Low-Level Bat Handle RoHS:否 制造商:OTTO 觸點(diǎn)形式: 開(kāi)關(guān)功能: 電流額定值: 電壓額定值 AC: 電壓額定值 DC: 功率額定值: 端接類(lèi)型: 安裝風(fēng)格: 端子密封: 觸點(diǎn)電鍍: 照明:
T7-122D1 制造商:OTTO 功能描述:Toggle Switches (ON) NONE ON 1 Pole Low-Level Bat Handle 制造商:OTTO Engineering Inc 功能描述:Switch Toggle (ON) None ON SPDT Bat Toggle Screw 16A 115VAC 28VDC Panel Mount with Threads
T7-122E1 制造商:OTTO 功能描述:Toggle Switches (ON) OFF (ON) 1 Pole Low-Level Bat Handle 制造商:OTTO Engineering Inc 功能描述:Switch Toggle (ON) OFF (ON) SPDT Bat Toggle Screw 16A 115VAC 28VDC Panel Mount with Threads