MT8920BE Mitel, MT8920BE Datasheet
MT8920BE
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MT8920BE Summary of contents
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... BUSY, DCS Registers IRQ, 24/32 Control Registers IACK, MS1 A5, STCH MMS ISO-CMOS ST-BUS ST-BUS Parallel Access Circuit MT8920BE MT8920BC MT8920BP MT8920BS Description The ST-BUS Parallel Access Circuit (STPA) provides a simple interface between Mitel’s ST-BUS and parallel system environments. Tx0 Dual Port Ram ...
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MT8920B CMOS 1 28 C4i 2 27 F0i 26 3 IACK, MS1 25 STi0 DS R/ ...
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Pin Description (continued) Pin # Name 13 A5 Address Bit A5 (Mode 1). This input is used to extend the address range of the STPA. A5 selects internal registers when high and Tx/Rx RAM’s when low. A5 Address Bit A5 ...
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... The ST-BUS is the primary means of access for voice, data and control information to Mitel’s family of digital telecommunications components, including North American and European digital trunk interfaces, ISDN U and S digital line interfaces, filter codecs, rate adapters, etc ...
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... ST-BUS channels, for both input and output serial streams, when the STPA is configured channel device. When used as a data interface to Mitel’s T1 trunk devices, however, only the first 24 consecutive RAM locations are mapped the 32 ST-BUS channels. This mapping follows a specific pattern which corresponds with the data streams used by Mitel‘ ...
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MT8920B CMOS 3-8 ...
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ADDRESS BITS • • • • • • • • • • • • • • • ...
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MT8920B CMOS Timing information for data transfers on this interface is shown in Figure 14. The Mode 1 interface is designed to operate directly with a 68000-type asynchronous bus but can easily accommodate most other popular microprocessors as well. Control ...
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Control Register 2 Bits Rx0 a) Control Register 2 Bits Tx0 P Rx0 b) Control Register 2 Bits ...
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MT8920B CMOS Interrupt Modes and Servicing Static Interrupt Mode A static interrupt is caused when an incoming byte matches a predefined byte. The incoming byte from a selected channel is stored in Interrupt Image Register (1/2) where it is compared ...
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... T1 or CEPT digital trunk link when used with Mitel’s trunk products. Referring to Figure 1, the Address Generator block generates and drives the external address lines A4-A0 ...
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... STCH Applications STi0 Parallel PBX to Digital Trunk Interface STo0 The STPA is an ideal component for interfacing parallel PBX environments to Mitel’s family of digital trunk devices. 1 Figure 11 shows a typical interface for both T1/ESF and CRC-4 CEPT digital trunks to a system utilizing DCS a parallel bus architecture ...
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AAA MT8920B CMOS 3-15 ...
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MT8920B CMOS Digital Signal Processor to ST-BUS Interface Mode 2 allows many high speed devices to be easily connected to the ST-BUS. Figure 12 shows a TMS32020 digital signal processor interfaced to the ST-BUS through the STPA. This simple interface ...
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Connecting the STPA to a shared ST-BUS Line The STPA’s STo0 and STo1 outputs cannot be directly forced into a high However, with some external logic, the STo0 output can be buffered by a three-state device, controlled by the STo1 ...
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MT8920B CMOS Absolute Maximum Ratings* Parameter 1 Supply Voltage 2 Voltage on any I/O pin 3 Current on any I/O pin 4 Storage Temperature 5 Package Power Dissipation * Exceeding these values may cause permanent damage. Functional operation under these ...
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AC Electrical Characteristics (V =5.0V ±5%,T =-40 to 85° Characteristics †† 1 Address to DS (CS) Low †† (CS) Low 3 DS (CS) Low to DTACK Low 4 Valid Data to DTACK Low (Read) ...
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MT8920B CMOS AC Electrical Characteristics (V =5.0V ±5%,T =-40 to 85° Characteristics 1 OE Low to Valid Data 2 Address Access Time 3 CS Low to Valid Data 4 Output Disable 5 Address Setup Time 6 Data Setup ...
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CHANNEL N - BIT 0 CONTENTION WINDOW C4i READ ADDRESS N or WRITE ADDRESS ( CONDITION 1: Access begins before contention window and finishes before ST-BUS access - No contention. OE, R/W BUSY CONDITION ...
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MT8920B CMOS AC Electrical Characteristics ((V =5.0V ±5%,TA=-40 to 85°C) CC Characteristics OE, WE, Address Enabled 2 C4i Low to Address Change OE, WE, Address Disabled 4 C4i Low to Output Enable Low 5 ...
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CHANNEL N-1 BIT 0 BIT 7 C4i STCH t STC Figure 18 - Mode 3 STCH Timing Diagram BIT 4 BIT 3 C4i STCH DCS t STC Figure 19 - Mode 3 DCS Timing Diagram CMOS CHANNEL N BIT 6 ...
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MT8920B CMOS AC Electrical Characteristics (V = 5.0V ± 5 -40 to 85° Characteristics 1 Clock C4i Period 2 Clock C4i Period High 3 Clock C4i Period Low 4 C4i Rise Time 5 C4i Fall Time ...
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CHANNEL CHANNEL 31 0 Bit BIT 7 Data Bus Figure 21 - Format of 2048 kbit/s ST-BUS Streams 2.0 V INPUTS 0.8 V 2.0 V OUTPUTS 0.8 V Figure 22 - Waveform Test Point Reference C L ...
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MT8920B CMOS NOTES: 3-26 ...