Description:

push memory byte onto the stack.  Read a byte 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] = port[program[pc + 1] : program[pc + 2]]
sp = sp + 1
pc = pc + 3

Flags Affected:

D	H	C	Z	N

Possible Errors:

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

Example:

pushmb 0x0080

Here we read the value from the aPortAddress port (0x0080) into a byte (0x02 in this example) and push it onto stack.

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

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