Programming a digital processor with a single connection
A digital processor is coupled to a processor programmer through a single programming connection (e.g., terminal, pin, etc.) coupled to the single conductor programming bus. The processor programmer comprises an instruction encoder/decoder, a Manchester encoder, a Manchester decoder, a bus receiver and a bus transmitter. The digital processor comprises an instruction encoder/decoder, a Manchester encoder, a Manchester decoder, a bus receiver, a bus transmitter, a central processing unit (CPU), and a program memory. The instruction encoder/decoder is coupled to the CPU and the program memory. The bus receivers and bus transmitters are coupled to the single conductor programming bus which is coupled to a connection, e.g., terminal, pin, ball, etc., on an integrated circuit package containing the digital processor. The instruction encoder/decoder is coupled to a programming console, e.g., a personal computer, workstation, etc.
1. A method for programming a digital processor through a single bit connection, said method comprising the steps of:
sending for a predetermined time period a serial bit stream having a unique data pattern to indicate entry into a programming mode from a programmer to a digital processor through a single bit bus, wherein the digital processor enters into the programming mode after the predetermined time period and due to recognition of the unique data pattern indicating entry into the programming mode;
sending the serial bit stream having program instructions from the programmer to the digital processor through the single bit bus;
sending the serial bit stream having data from the programmer to the digital processor through the single bit bus; and
receiving the serial bit stream having the program instructions and the data by the digital processor from the single bit bus, wherein the digital processor stores the program instructions and the data in a memory of the digital processor;
wherein the steps of sending the serial bit stream having the program instructions and the data from the programmer to the digital processor through the single bit bus comprise the steps of:
encoding the program instructions and the data from the programmer into the serial bit stream;
sending the serial bit stream having the program instructions and the data to a single bit bus driver in the programmer, wherein the single bit bus driver is coupled to the single bit bus;
wherein the steps of receiving the serial bit stream having the program instructions and the data by the digital processor from the single bit bus comprise the steps of:
receiving the serial bit stream having the program instructions and the data with a single bit bus receiver in the digital processor, wherein the single bit bus receiver is coupled to the single bit bus;
decoding the program instructions and the data from the serial bit bus receiver; and
storing the decoded program instructions and the data into a program memory in the digital processor.
2. The method according to claim 1 , wherein the serial bit stream is a Manchester-encoded protocol serial bit stream.
3. The method according to claim 2 , wherein a serial clock is synchronized with the serial bit stream at the single bit programming connection.
4. The method according to claim 2 , further comprising the step of reading the program memory through the single bit programming connection.
5. The method according to claim 2 , further comprising the step of entering a test mode through the single bit programming connection.