RS8973 Mindspeed Technologies, RS8973 Datasheet - Page 42

• Manufacturer Part Number: RS8973
• Description: Single-chip Sdsl/hdsl Transceiver
• Manufacturer: Mindspeed Technologies

2.0 Functional Description
2.5 Microcomputer Interface
2.5.1 Source Code
2.5.2 Microcomputer Read/Write
2-18
2.5 Microcomputer Interface
The microcomputer interface provides operational mode control and status
through internal registers. A microcomputer write sets the operating modes to the
appropriate registers. A read to a register verifies the operating mode or provides
the status. The MCI can be programmed to generate an interrupt on certain
conditions.
Conexant provides portable C-source code under a no-cost licensing agreement.
This source code provides a start-up procedure, as well as diagnostic and system
monitoring functions.
The MCI uses either an 8-bit-wide multiplexed address-data bus, or an 8-bit-wide
data bus and a separate 8-bit-wide address bus for external data communications.
The interface provides access to the internal control and status registers,
coefficients, and microcode RAM. The interface is compatible with Intel or
Motorola microcomputers, and is configured with the inputs, MOTEL and
MUXED.
this address space provide configuration, control, status, and monitoring
capabilities.
read, the upper-byte is latched at the corresponding value. This ensures that
multiple byte values correspond to the same reading.
coefficients require an indirect access.
• MOTEL high selects Motorola-type microcomputer and uses control
• MUXED high configures the interface to use the multiplexed address-data
• The READY pin is provided to indicate when the RS8973 is ready to
The MCI provides access to a 256-byte internal address space. The registers in
Meter values are read lower-byte, then upper-byte. When the lower-byte is
Most information can be directly read or written; however, the filter
signals ALE, CS, DS, and R/W. MOTEL low selects Intel-type
microcomputer and uses control signals ALE, CS, RD, and WR.
bus with both the address and data on the AD[7:0] pins. MUXED low
configures the interface to use separate address and data bus with the data
on the AD[7:0] pins and the address on the ADDR[7:0] pins.
transfer data and can be used by the microcomputer to insert wait states in
read or write cycles.
Preliminary Information
Conexant
Single-Chip SDSL/HDSL Transceiver
N8973DSD
RS8973