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Motorola DSP56301 User Manual

Page 298

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DSP56301 User’s Manual

; 7-0). The memory is selected by the Address Attribute AA1 and is

; accessed with 31 wait states.

;

; The EPROM bootstrap code expects first to read 3 bytes specifying the

; number of program words, then 3 bytes specifying the address to

; start loading the program words, and then 3 bytes for each program word

; to be loaded. The number of words, the starting address, and the program

; words are read least significant byte first followed by the mid and

; then by the most significant byte.

;

; The program words will be condensed into 24-bit words and stored in

; contiguous PRAM memory locations starting at the specified starting

; address. After the program words are read, program execution starts

; from the same address where loading started.

;

;

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

; If MD:MC:MB:MA=x010, then it loads the program RAM from the SCI interface.

;

; The SCI bootstrap code expects first to receive 3 bytes specifying the

; number of program words, then 3 bytes specifying the address to

; start loading the program words, and then 3 bytes for each program word

; to be loaded. The number of words, the starting address, and the program

; words are received least significant byte first followed by the mid and

; then by the most significant byte.

;

; The program words will be condensed into 24-bit words and stored in

; contiguous PRAM memory locations starting at the specified starting

; address. After reading the program words, program execution starts

; from the same address where loading started.

;

; The SCI is programmed to work in asynchronous mode with 8 data bits, 1

; stop bit and no parity. The clock source is external and the clock

; frequency must be 16x the baud rate. After each byte is received, it

; is echoed back through the SCI transmitter.

;

;

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

; If MD:MC:MB:MA=x011, then it loads the program RAM from the Host Interface

; programmed to operate in the Universal Bus mode supporting DSP-to-DSP

; glueless connection.

;

; The HI32 bootstrap code expects first to read a 24-bit word specifying

; the number of program words, then a 24-bit word specifying the

; address to start loading the program words, and then 24-bit word for

; each program word to be loaded.

;

; The program words will be stored in contiguous PRAM memory

; locations starting at the specified starting address. After

; the program words are read, program execution starts from the same

; address where loading started.

;

; The Host Interface bootstrap load program may be stopped by setting the

; Host Flag 0 (HF0) in HCTR register. This will start execution of the

; loaded program from the specified starting address.

;

; During the access, the HAEN and HA[10 – 3] pins must be driven low; pins

; HA[2 – 0] select the HI32 registers.

; Before booting through the Host Interface it is recommended that the