Operations And Commands - RCA CDPl8S693 User Manual

54 User Manual for Microboard Computer Development System CDP18S693 & CDP18S694
Before starting a programming operation, be sure
that the external program m ing power supply
(connected to J3) is at the proper voltage. Excessive
voltage can cause permanent damage to a PROM.
It is recommended that the programmer module not
be run on an extender card in the MCDS system. An
extender card will exaggerate bus-loading effects and
may lead to intermittent operation of the programmer,
particularly in systems already loaded with extra I/O
or memory modules. If anomalous operation is
observed, a first step should be to remove any extender
cards and extraneous modules from the system.

Operations and Commands

Following is a discussion of each command and
operating sequence.
Programming Operations—
The "P " Command
The system is capable of programming the RCA
CDPl8U42 CMOS PROM and Intel 2708, 2758, and
2716 type PROM 's. Data to be programmed comes
from the RAM Buffer area, pages 8 and up in the
MCDS RAM. The data must first be loaded into the
appropriate page(s) by COPYing another PROM into
them or by loading the appropriate section of a tape
file into them. The file loading, when requested, leads
automatically into a programming cycle. Refer to the
section, File Reader Subroutines for a detailed
discussion of the file loaders. Programming begins
immediately from the specified page.
Procedure
The program always begins by printing
MCDS PROM PROGRAMMER VER X
F, Y, P, C, S, J, U?
After the user types the letter 'P'\ the program asks
TYPE #?
The user should enter one of the following:
1842, 2708, 2758, or 2716
followed by a (CR).
The program next asks if operation is to be with true
or inverted data by typing
LOGIC-P, N?
A "P " response causes the operation to occur with true
(non-inverted) data; an "N " response causes the
operation to proceed using an inverse of the data. For
example, to copy one PROM into another, inverting
data, one could copy the master PROM using positive
logic and program the copy PROM using negative
logic or vice-versa. Negative logic would not be used
for both the copy and program step because that would
give a double inversion.
The program next asks
(T)APE OR (R)AM?
The user should enter the letter "R " if the data to be
programmed is already in the buffer RAM.
The next prompt is
PAGE# =
asking for the first page on which data is located. Data
is taken from that page and subsequent pages as
required for the PROM being programmed.
If the user enters the letter "T", indicating data tobe
programmed is on a tape file, the program will ask for
the unit by typing
TAPE#
The user should respond with either a "0" or a " 1".
Next, the program asks for the address range of the
PROM by typing
LOWEST PROM ADDRESS (XX00)?
The user should respond with a four-digit number
followed by a (CR). This number should be the lowest
address of data to be programmed into the PROM.
For instance, if a 2704 PROM is to be programmed for
data addresses 0200 through 03FF, then 0200 would be
typed as a response. A default value of 0000 is entered
if the user hits the carriage return without typing in a
number. If a number is entered, all four digits must be
entered. The file reader searches the object file and
loads only the data falling between the lowest address
specified and up to 2 kilobytes above thataddress. The
appropriate data is copied into RAM starting at page 8
and then the actual programming begins automatically.
Note that programming will be initiated when the 2-
kilobyte RAM area is filled or an end-of-file marker is
read from tape. Thus, if the user enters an improper
start address, the PROM will be programmed with
invalid data.
Any programming operation is automatically
followed by a VERIFY sequence. If the verify is
successful, the program types
DONE
If programming is not successful, a list of errors is
typed. This list can be stopped by depressing the
BREAK key until the
***ABORTED***
message is typed.
If programming has been done successfully, a
message such as
REPROGRAM 1842?
appears, identifying the PROM type just program­
med. If the user does not want to program another
device of the same type with the same information, he
should type "N" for NO. If the programming of
another PROM of the same type is required, the user
should take the following steps:
—Shut off power switch S2
—Remove the PROM just programmed
—Insert the new PROM to be programmed
—Turn on switch S2
—Type the letter "Y" for yes on the terminal.
Another programming sequence will begin immedi­
ately.
During a program m ing operation, the LED
indicator labeled PROG on the programmer board is
ON, providing a visual indication of operation. The
programming operation can be halted at any time by