Motorola M68CPU32BUG, Руководство пользователя

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SYSTEM CALLS
M68CPU32BUG/D REV 1 5-5
.CHANGEV
Parse Value, Assign to Variable
.CHANGEV
5.2.2 Parse Value, Assign to Variable
SYSCALL .CHANGEV
TRAP CODE: $0067
Parse a value in the user specified buffer. If the user specified buffer is empty, the user is
prompted for a new value, otherwise update the integer offset into the buffer to skip the value.
The new value is displayed and assigned to the variable unless the user’s input is an empty string.
Entry Conditions:
SP ==> Address of 32-bit offset into user’s buffer
Address of user’s buffer (pointer/count format string)
Address of 32-bit integer variable to change
Address of string to use in prompting and displaying value
Exit Conditions:
SP ==> Top of stack
EXAMPLE
PROMPT DC.B $14,’COUNT = |10,8|’
GETCOUNT PEA PROMPT(PC)
Point to prompt string
PEA COUNT
Point to variable to change
PEA BUFFER
Point to buffer
PEA POINT
Point to offset into buffer
SYSCALL .CHANGEV
Make the system call
RTS
COUNT changed, return