EMAC PRIMER Instruction Manual page 81

the way you expected. You will find as you are starting out, most of your programming problems will be caused by an
incomplete knowledge of the way an instruction works. For this reason it is helpful to review the instruction definitions in
the previous lessons or read supplemental textbooks. For example, a common mistake is to expect the execution of a
DCX instruction (decrement register pair) to set the condition flags. The definition of this instruction says that no flags are
affected. So if this instruction was used in a conditional loop to control how many times the loop occurred, the loop may go
on infinitely.
If you have access to a PC compatible, you may want to build your own 8085 programming environment which will speed
up programming greatly. This environment requires the following: a simple text editor, an 8085 assembler that generates
Intel hex files, a terminal emulator with file upload capability, and finally a PRIMER with a Standard or Deluxe Upgrade
option (or at least a serial port) and MOS version 2.5 or greater. In this environment you write your program with the text
editor and generate the hex file by assembling the program. Pressing "Func." then "3" will then enable the PRIMER's serial
port to receive a hex file. After this, the displays will show "rEC.." indicating that the PRIMER is ready to receive the data.
After an ending record is received, (a record in which the fourth pair of digits following the colon is 01), the PRIMER will
return to entry mode. If any errors occur while receiving the hex file "Err.." will be displayed followed by a hex number. The
bits in this number, after it is converted to binary indicate the following errors:
Pressing a key after the error message will put the PRIMER back into entry mode. Receiving a hex file may be aborted any
time by resetting the PRIMER or by sending an escape character (1Bh) to the PRIMER's serial port. Sending an escape
character will result in an "Err..08".
The program is loaded in the PRIMER's memory by using the terminal emulator's upload (or send) option to send the hex
file to the PRIMER. In this environment the program is quickly and accurately loaded, eliminating the tedious process of
hand assembling the program and typing it in at the PRIMER's keypad.
If you have the Standard or Deluxe Upgrade option, another programming aid is EMOS which is an operating system in
which all interaction is through the serial port and is intended to be used with a data terminal or a terminal emulator running
on a PC. It is an enhanced MOS with features such as dump, fill, or move memory, view register contents, read input
ports, write output ports, hex and decimal addition and subtraction, program tracing, single stepping, and it has a built in
disassembler.
BIT# ERROR
0 (not used)
1 checksum error
2 non-hex character encountered
3 escape character encountered
4-7 (not used)
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