Description:

Read a short from the memory-mapped IO port specified by the address parameter and push it onto the top of the stack .

Data (2 bytes):

short: address of the memory-mapped IO port

Pseudo Code:

stack[sp] = (short) port[program[pc + 1] : program[pc + 2]]
sp = sp + 2
pc = pc + 3

Flags Affected:

D	H	C	Z	N

Possible Errors:

tvmStackOverflow	-	There is no more room on the stack to push the short.
tvmStackIOErr	-	The read operation from the memory-mapped IO port is invalid.

Example:

pushms 0x0480

Here we read the value from the aPortA2DValue0 port (0x0480) into a short (0x0323 in this example) and push it onto stack.

Before stack   top 1 0xAA 2 0x32 3 0x02   bottom

After stack   top 1 0x23 2 0x03 3 0xAA 4 0x32 5 0x02   bottom