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EV80C196KB Microcontroller Evaluation Board User's Manual -49-
RISM Commands
This section will detail the operation of each of the commands sent to the RISM.
SET-DLE-FLAG
( Code OOH )
This command sets the DLE-FLAG. This will force the next character received by
the RISM to be treated as data even if its value corresponds to a RISM command.
The code which overrides the normal selection of command or data also clears the
DLE-FLAG so that it applies only to the first character received after the
SET-DLE-FLAG
command.
TRANSMIT ( Code 02H )
This command will transmit the lower eight bits of the RISM-DATA register to the
host, right shift the data register eight places, and increment the RISM-ADDR regis-
ter. Sequential TRANSMIT commands are used to read the RISM-DATA register
and the RISM-ADDR re ister indicates the address that corresponds to the least
significant byte in the RI M-DATA register.
ti
READ-BYTE
( Code 04H )
This command will read the byte of memory pointed to by the RISM-ADDR register
and place the result in the least significant byte of the RISM-DATA register.
READ-WORD ( Code 05H )
This command will read the word of memory pointed to by the RISM-ADDR register
and place the result in the least significant word of the RISM-DATA register.
READ-DOUBLE ( Code 06H )
This command will read the double-word of memory pointed to by the address
register and place the result in the RISM-DATA register.
WRITE-BYTE ( Code 07H )
This command stores the least significant byte of the RISM_DATA register in the
byte of memory pointed to by the RISM-ADDR register and increments the
RISM-ADDR register (by one) to point at the next memory byte.
WRITE-WORD ( Code 08H )
This command stores the least significant word of the RISM-DATA register in the
word of memory pointed to by the RISM-ADDR register and increments the
RISM-ADDR register (by two) to point at the next memory word.
WRITE-DOUBLE
( Code 09H )
This command stores the RISM-DATA register in the double-word of memory
pointed to by the RISM-ADDR register and increments the RISM-ADDR register (by
four) to point at the next memory double-word.
LOAD-ADDRESS ( Code OAH )
This command loads the RISM-ADDR register with the least significant word in the
RISM-DATA register.
INDIRECT-ADDRESS ( Code OBH )
This command reads the memory word pointed to by the RISM-ADDR and stores it
into the RISM-ADDR register. The RISM-DATA register is not modified by this
command.
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