Measurable objects - ISDN developing card

ISDN developing card is a product of the American MITEL Semiconductor, later ZARLINK, which firm makes integrated circuits for communication purposes. There are integrated circuits on the card installable into a PC, which can realize different standard communication interfaces that can be connected with each other with the help of a time-sharing switching field. We can program the interface circuits on the card through a PC interface with a handling program, or we can get the state of the interface this way.

Simplified block diagram of the card:

• s - internal time-sharing databuses (ST-bus)
• p - a microprocessor bus. Programming of tools, and reading of the state information can be made through this.

Main functional units of the card:

Number	Description	Type number of ZARLINK IC realizing the functional unit
1	G.703 2048 kbit/s interface (30-channel PCM interface, ISDN PRI interface)	MH89790, short description, programming
2	G.703 1544 kbit/s interface (24-channel PCM interface - according to American standard)	MH 89760
3	ISDN S0 interface	MT 8930
4	ISDN U interface (See its description in chapter ?Interfaces?)	MT 8972
5	Digital telephone (Circuit, which realizes the digital telecommunication functions. Handset must be connected separately!)	MT 8992
6	HDLC kontroller (This circuit makes the framing of messages in case of ISDN D channel and CCS signal system)	MT 8952B
7	Time-sharing switching field	MT8980 short description, programming

Notes:
G.703 interfaces does not have microprocessor interfaces, their control and the reading of state information happen through ST buses.

Card can be used in measurements for testing of the interfaces, and for displaying the contents of time frames (time-gaps).

Usage of the card:

Card is installed in the PC at the measuring place. We can access to the communication interfaces through RJ11 type connectors:

The user program named IES written under DOS can be found on the local drive, in the \IES subdirectory.

User?s manual of the program:

• 1.) Start the IES program! (It can be started under Windows, in a DOS window.)
• 2.) The card installed to the computer is indicated by a list displayed on the screen, press ENTER.
• 3.) Press ENTER to the next image, too.
• 4.) Next image will show the registers (digital telephone) of one of the interfaces of developing card.
• 5.) The command line can be displayed by pressing the "/" button.
• 6.) We can select menu displaying the registers of the required interface in the display menu. (PCM interface can be displayed under CEPT menu element, and the PCM switch can be displayed under DX menu element!)
  Note: This development card is an American card, where the European PCM interface was marked with the acronym of this European (it was ceased since then) standardizing organization (CEPT).
• 7.) We can select the clock signal resource of developing card in the timing menu (your own clock signal resource is the DPLL, and all the other clock signal resources are clocks obtained from a data signal from one of the other interfaces).
• 8.) We can change the value of the registers in the register menu with the grey + and - buttons. Program is able to draw the value of the registers (displaying changes), it can be started with pressing ENTER.

Attached documentations (available only at the measuring place!):

• MITEL: ISDN express card manual
• MITEL: Digital Communications Handbook (description of the integrated circuits realizing the interfaces)