Abstract: A frequency divider circuit is provided having an even number of amplifier stages connected in series with the output of the last amplifier stage connected to the input of the first amplifier stage; and modulating means responsive to an input signal to be frequency divided, for modulating the propagation delay through each of the amplifier stages about the period of the input signal to be divided, such that when propagation through the odd amplifier stages increases, the propagation through the even amplifier stages decreases. The frequency divider circuit can be used as a pre-scaler of a radio receiver circuit.

Abstract: An integrated circuit contains a microprocessor core, program memory and separate data storage, together with analog and digital signal processing circuitry. The ALU is 16 bits wide, but a 32-bit shift unit is provided, using a pair of 16-bit registers. The processor has a fixed length instruction format, with an instruction set including multiply and divide operations which use the shift unit over several cycles. No interrupts are provided. external pins of the integrated circuit allow for single stepping and other debug operations, and a serial interface (SIF) which allows external communication of test dat or working data as necessary. The serial interface has four wires (SERIN, SEROUT, SERCLK, SERLOADB), allowing handshaking with a master apparatus, and allowing direct access to the memory space of the processor core, without specific program control.

Abstract: A frequency divider circuit is provided having an even number of amplifier stages connected in series with the output of the the last amplifier stage connected to the input of the first amplifier stage; and modulating means responsive to an input signal to be frequency divided, for modulating the propagation delay through each of the amplifier stages about the period of the input signal to be divided, such that when propagation through the odd amplifier stages increases, the propagation through the even amplifier stages decreases. The frequency divider circuit can be used as a pre-scaler of a radio receiver circuit.

Abstract: An integrated circuit contains a microprocessor core, program memory and separate data storage, together with analog and digital signal processing circuitry. The ALU is 16 bits wide, but a 32-bit shift unit is provided, using a pair of 16-bit registers. The processor has a fixed length instruction format, with an instruction set including multiply and divide operations which use the shift unit over several cycles. No interrupts are provided. external pins of the integrated circuit allow for single stepping and other debug operations, and a serial interface (SIF) which allows external communication of test dat or working data as necessary. The serial interface has four wires (SERIN, SEROUT, SERCLK, SERLOADB), allowing handshaking with a master apparatus, and allowing direct access to the memory space of the processor core, without specific program control.

Abstract: An integrated circuit contains a microprocessor core, program memory and separate data storage, together with analogue and digital signal processing circuitry. The ALU is 16 bits wide, but a 32-bit shift unit is provided, using a pair of 16-bit registers. The processor has a fixed length instruction format, with an instruction set including multiply and divide operations which use the shift unit over several cycles. No interrupts are provided. External pins of the integrated circuit allow for single stepping and other debug operations, and a serial interface (SIF) which allows external communication of test data or working data as necessary. The serial interface has four wires (SERIN, SEROUT, SER-CLK, SERLOADB), allowing handshaking with a master apparatus, and allowing direct access to the memory space of the processor core, without specific program control.