Cromemco BYTESAVER User manual

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Cromemeo
lncorporal."
Speclallsls In compulil'. and pel"lpherals
2400 CH~RlESTON AD~ MOUNTAIN View, C.o._

···v
BYTESAYER
INSTRUCTION MANUAL.
eBytesaver Assembly eBytesaver Parts List
eBytemover Software e2708-2704 PROM Data
eBytemover Assembly Listing
©Copyright 1977. All rights reserved.
C3
C
romemeo
incorporated
Specialists in computers and peripherals
.2400 CHARLESTON RD., MOUNTAIN VIEW, CA 94043

BYTESAVER ASSEMBLY
-
~ :--=- -:--~:-:_~ -
---------------------------------_ ...... = - - - - - ~ - ... - ~ ~
Introduction
6. Install the p.c. board switch (SW1) in the upper left corner
of the p.c. board.
The Cromemco Bytesaver is a read/write, non-volatile
memory board, plug compatible with the Standard-l 00 (S-100)
microcomputer bus. The Bytesaver has the capacity for eight
2708 U.V. erasable PROMs for afull 8K bytes of memory.
The Bytesaver contains an integral PROM programmer
along with aDC-to-DC supply for generating the programming
voltage. Programming
is accomplished by aseries of memory
write operations to the PROM being programmed.
Cromemco provides the necessary programming software.
Our Bytemover
software, described later in this manual, allows
convenient PROM programming using your computer's front
panel sense switches to control the operation (e.g. to select one
of the eight PROMS to be programmed). Programming can also
be carried
out using the l-80 Monitor supplied with our l-80
CPU card and our l-80 microcomputer system.
Assembl~ Instructions
The Cromemco Bytesaver™ kit can be assembled in about
one evening. All components are mounted on the component
side of the p.c. board (the side with the printed legend) and
soldered on
the opposite side. Be sure to use high-quality, rosin
core solder for the assembly and afine-tipped, low-wattage
soldering iron.
1.
Solder the 10 14-pin IC sockets, the 616-pin IC sockets
and
the 824-pin sockets in position.
7. Install
the Cromemco high-speed pulse transformer (Model
XT8K)
in position Tl. Note that the leads are asymmetrically
arranged so
there is only one possible orientation.
8. Install IC14, the positive 12V regulator IC. Use a6-32
by
1/4" screw and nut.
9. Initially install
the heatsink in the upper right corner of the
p.c. board by just starting the nuts on the 6-32 by 3/8" screws.
Install IC12 and IC13
but be sure to place the insulating washer
between IC13 and
the heatsink_ The nylon screw must be used
to secure IC13. It is important that the screw be inserted from
the p.c. board side so the screw head is against the foil side. Be
aware that the insulating washer may have to be trimmed with a
pair
of scissors to clear the protrusions in the heatsink. Tighten
the nuts on the screws in the heatsink assembly only after all
the screws have been inserted. Take care that the leads of the
voltage regulators do not come in contact with the sides of the
openings in the heatsink. Although voltage regulators IC12,
IC13
and IC14 may look similar, they are not interchangeable.
10. Install
three jumper wires to select where the Bytesaver is
to reside in memory. Each of the three high-order address lines
(A15,
A14 and A13) may be tied to either the corresponding
"H" or "L" terminal. For example, in order for the Bytesaver to
reside in the top 8K of memory, the three jumpers should be in-
stalled
as shown below:
3. Next, install
the lN914 diodes. We recommend that no
diode be installed in the diode position just below transistor 00.
Since we recommend that the PROM containing the Bytemover
software be inserted in PROM position zero, installing this diode
may allow accidental programming of this PROM.
When installing
the diodes, be careful to orient them pro-
perly, by noting
the position of the cathode (banded) end. Due
to the close spacing of the holes in the p.c. board, all diodes
should be
mounted on end.
Notes
This adjustment causes the Bytesaver to reside in the top 8K of
the memory map.
HIO
LO 0 )A14
o
o
A15<OHI
OLO
OHI
A13<O LO
o
Interrupts: If you plan to have your computer respond to
interrupts while executing aprogram stored in the Bytesaver
memory, asmall modification is required to the Bytesaver
circuit. This modification is shown in Note 1 on the Bytesaver
schematic.
Your Bytesaver is now fully assembled. Detailed operating in-
structions are given in the Bytemover software section of this
manual.
11. Install
the ICs in their sockets, being careful to orient pin 1
of each IC as shown by the small white dot on the p.c. board at
each IC position. Install aPROM containing the Bytemover
software in PROM position zero.
R1 47K
yellow-violet-orange
R2 10K
brown-black-orange
R3
180
brown-gray-brown
R4 1K
brown-black-red
R5
9.1K
white-brown-red
R6 1.5K
brown-green-red
R7 1.2K
brown-red-red
R8 47
yellow-violet-black
R9 1K
brown-black-red
R10 10
brown-black-black
R11
5.6K green-blue-red
R12 5.6K green-blue-red
R13 10K
brown-black-orange
R14 5.6K green-blue-red
R15 180
brown-gray-brown
R16-R31 18K
brown-gray-orange
R32-R39 4.7K
yellow-violet-red
Solder the following %Watt resistors in position:
l~2.
5. Solder the transistors in place taking care to orient them
properly. Note that 08 and 09 are 2N3906 transistors and 010
is a type MPS6560. All other transistors are type 2N3904.
4. Install the 23 capacitors as shown on the p.c. board. Be
careful to orient the electrolytic capacitors with the positive
i'-' (+) end as shown on the board.
I
Wait State: Should you wish to use low speed 2704s or 2708s
(access times greater than 450 ns) in your Bytesaver, be aware
there is aprovision for a wait state. Simply insert the jumper
wire between IC10 and ICll. No jumper need be inserted when
using full speed PROMs. Jumper is also required for 4MHz
operation.
1
..

BYTESAVER PARTS LIST
-
::= -...:.:.~ ~ ..... -- -- - ....=.~
=-=-==-====="='='=='===
-- ------- ---- ---
----------------------------------...::::;:::: = --- =='="=- ::=-~~
Programming PROMs
PROM programming with the Bytesaver is carried out by a
sequence
of memory write operations to the Bytesaver card. A
sequence of approximately
100 memory write operations is
required to write the data into each location of every PROM
that you wish to program. This sequence of memory write oper-
ations
is carried out automatically when using the special
instructions
of Cromemco software. The Cromemco Z-80
Monitor,
the Resident Operating System, and the 3K Control
Basic Interpreter
all have provision for PROM programming with
the Bytesaver card. If your computer is equipped with front
panel sense switches, our Bytemover software can be used for
PROM programming. Operation
of the Bytemover software is
described in the next section.
B~tesaver Parts List
Transistors
Integrated Circuits
IC1 74123
IC2 7474
IC3 7402
1C4 7406
IC5 7406
IC6 7402
IC7 ' .. 7406
IC8 7442
IC9
74L04
IC10 7410
IC11 74LS04
IC12* 340T-5.0 or 7805
IC13* 320T-5.0 or 7905
IC14* 340T-12 or 7812
IC15 7432 or 74LS32
IC16 74367
IC17 74367
IC18 74367
IC19 74367
Miscellaneous
SW1. ............
... p.c. board switch
T1 XT8K pulse transformer
Hardware
36-32
by 3/8" screws
1 ; 6-32 by 1/4" screw
1* * 6-32
by 3/8" nylon screw
56-32 nuts
1Heatsink
1Insulating washer
Sockets
10 14-pin
616-pin
824-pin
·
2N3904
· 2N3906
................MPS6560
·
2N3904
Diodes
01-D19 1 N914 or 1N4531
Resistors
R1 47K
R2 10K
R3 180
R4 1K
R5 9.1 K
R6
1.5K
R7 1.2K
R8 47
R9
1K
R10 10
R11
5.6K
R12 ' 5.6K
R13 10K
R14 5.6K
R15 180
R16-R31 18K
R32-39 A.7K
Capacitors
C1-C8 0.1 uF
C9-C15 10
uF, 50V
C16 005
C17 680 pF
C18
01 uF
C19 680 pF
C20 150 pF
C21-e23 0.1 uF
QO-Q7 .
aa,Q9 ..
Q10 ....
Q11,Q12
Notes
•
*The three voltage regulator ICs OC12, IC13 &
IC14) may look physically similar, however
they are not interchangeable. Each must be in
the proper IC location.
*
*The nylon screw is used to secure IC13. It is
important that the screw be inserted from the
p.c. board side
of the assembly so the head of
the screw is agai nst the foil side of the board.
2

BYTEMOVER SOFTWARE
-- -- ... ..-.. ...-. ..... - - --- - -
- -- - --
- -----------
-::"":5 ====~==5.e..:==
--------------------------------...;::::;:::' - ~ -- ~ ~ ........... ~ .----.
Introduetion Step B~ Step Instruetions
1. Before using the Bytesaver, you must install three jumper
wires to set the location of Bytesaver in memory. This adjust-
ment is shown in Figure 1. The assembled Bytesaver comes with
A13, A14 and A15 each tied
to the corresponding HI pad to
position the board at the very top of memory. In the following
instructions it
is assumed this is the jumper connection used.
Cromemco Bytemover software is designed to be used with
the Cromemco 8K Bytesaver described. When you purchase
aBytesaver with
one 2708 PROM, the Bytemover software is
preprogrammed in that PROM.
The PROM containing the Bytemover software is normally
inserted
into PROM location zero on the Bytesaver board.
The Bytemover software can be used to program aPROM
in any of the PROM locations on the Bytesaver board. The
By ternover software can also be used to transfer programs from
PROM
to RAM.
The operation of the Bytemover software is controlled by
setting
front panel sense switches on any S-100 bus-compatible
computer. However, to use the Bytemover software there must
be at least one RAM board in the computer beginning at loca-
tion zero in the memory map. Furthermore, this RAM board
must be unprotected for proper execution of the By ternover
software.
A150
HIO
LOO
HIO
LOO
A130
EJ
HIO D
A~~g 0
Programming
Partiall~ Filled PROMs
Software can be loaded into a 2704 or 2708 in as small in-
crements as you desire provided it is added to previously unused
areas
in that PROM.
This
is done by first using Bytemover to move the current
contents of the PROM down to RAM, adding the new software
to an area of RAM which corresponds to the unused portion of
the PROM and finally using By ternover again to re-program the
PROM with the new software.
Although
the entire PROM must always be programmed, it
never hurts
to re-write the same information over again. And, of
course, an erased PROM in which all bits are "1" may be pro-
grammed at any time.
In general, it is OK to write a "1" over a "1", a "0" over a
"0", or a "0" over a "1". But in order to write a "1" over a "0",
the PROM must first be completely erased.
If the PROM to which you want to add software is PROM
zero
on the Bytesaver board, turn off the A.C. power to the
computer and install a 1N914 diode just below 00 (see step 3 of
the Bytesaver assembly instructions).
Turn the power back on and move Bytemover down to
RAM zero by following Example 1. Addthe new software to an
area
of RAM which corresponds to an unused portion of PROM
zero.Re-program PROM zero by following Example 4
of this
manual. Note
that you need not erase the PROM to do this.
Turn the computer power off and remove the 1N914 diode
below
00.
PROM Programming Time
The Bytesaver software supplied here is designed to pro-
gram aPROM in approximately 30 seconds. We have found that
this is generally asufficiently long period of programming time.
However-to be completely within the manufacturer's specifica-
tions-the PROM should be programmed for 2 to 3minutes.
If you wish
to program your PROMs for longer than 30 sec-
~ onds, the Bytemover software may be easily modified. Simply
change
the contents of location 77H from 40H to Oaf-,!. Now
you
must manually time the programming operation and de-
press
the stop switch at the end of the operation.
3
FIGURE 1. This diagram illustrates the positioning of the Byte-
saver address
in memory. The preassembled Bytesaver comes
with A15, A
14 and A 13 connected to the corresponding HI ter-
minals so memory address occurs when these lines are HI. Any
or all of these address lines may be connected to the correspon-
ding LO terminal to move the memory board lower in memory.
Consequently, there
are eight positions in which this board may
~d.
2. Turn off all power to the computer and plug in the Byte-
saver board.
3.
Be sure the program power on the Bytesaver is turned off
(program power switch in the down position).
4. Turn on the computer. Raise the reset switch, the stop
switch and then raise the reset switch once again to initialize the
computer.
5. Raise address switches A15, A14 and A13. All other ad-
dress switches should be in the down position.
6. Raise the examine switch. You are now examining the con-
tents of the first byte of PROM in PROM location zero of the
Bytesaver memory board (memory location 340 000). If the
PROM supplied with your Bytesaver is in this PROM location,
the data lights will read "061,"the first byte of the Bytemover
program.
Example 1: Transfer the Bytemover program from PROM to
RAM beginning at location zero in RAM.
1. Raise
the reset switch.
2. Depress the unprotect switch (on the Altair front panel).
3. Raise A 15, A14 and A13. Raise the examine switch. The
data lights shou Id read "061" octal.
4. Now set
the sense switches for the task to be done, refering
to Figure 2.
A15
Down
to transfer from Prom to Ram.
A14 Down for
the transfer of 1K bytes.
A13 Down
All down since we are transferring from the
A12
Down
A
11
Down PROM
that contains By ternover (PROM 0).
A10
Down
A9 Down All
down for storage to begin at location
A8 Down zero
in RAM.

BYTEMOVER SOFTWARE
-
== :;-=-- -=~-~;:;-~ -
--------------------------------...;= - -.-..- - - ~ ~ ~ ~ - ~ ~
A15
A14 A13 A12
A11
A10
A9 A8
0 0 000000
UP UP
LSB MSB
To program aMSB LSB
For a 7K transfer.
PROM. PROM address
location in incre- Selection
of RAM address in 1K
DOWN DOWN
ments of 1K from the PROM in
increments.
To movelfrom which Bytemover is stored.
PROM
to RAM.
For a 1K transfer.
FIGURE 2: Function of the sense switches in Bytemover.
5. Push the run switch. In less than one second, the contents of
PROM will be transfered
to RAM. The contents of PROM are
unaffected by this operation.
6. Raise
the stop switch.
7. Raise
the reset switch. Note that the data Iights read "061".
Example 2: Program a 2708 PROM inserted in PROM location
one. This PROM
is to be programmed with the contents of the
first 1K bytes of RAM beginning at location zero in memory.
The Bytesaver software
is still in the PROM installed at PROM
location zero
on the Bytesaver board.
1. Raise
the reset switch.
2. Depress
the unprotect switch (on the Altair front panel).
3. Raise A15, A14 and A13. Raise
the examine switch. The
data li.g\ts should read '~061" octal. .
4.
RaisE! the protel:t sWitch on the Bytsaver board (I.e. program
power switch
to the on position). The protect light on the front
panel should go off when this switch is raised.
5. Now set
the sense switches for the task to be done:
A15 Up
to program aPROM.
A14 Down (always down
for PROM programming).
A13 Down
To select the PROM 1K higher in memory
A12 Down
-=i
All
Up
than the PROM that contains Bytemover.
Al0
Down
All down for transfer to begin at location
A9 Down
A8 Down zero
in RAM.
6. Push the run switch. Note that panel light A9 is blinking at a
rate
of about twice per second. When this light stops blinking,
the PROM programming is complete.
7. Raise
the stop switch.
8. Now note
the INTE light on the front panel. If this light is
on, the Bytemover Verifier has verifed that the contents of the
programmed PROM are indeed identical to the contents of the
selected 1K bytes of RAM. If this light is off, the PROM has not
programmed correctly. This could be due to adefective PROM.
4
Example 3: Altair 8K BASIC can be stored in seven 2708
PROMs. Given that these seven PROMs are in PROM locations
one through seven
of the Bytesaver board, 8K BASIC can easily
be transferred into
RAM using the following procedure:
1. Raise
the reset switch.
2. Depress
the unprotect switch (on the Altair front panel).
3. Raise A15, A14 and A13. Raise
the examine switch. The "'- ~
data lights should read "061" octal. ~
4. Now set the sense switches for the task to be done:
A15 Down to transfer from PROM to RAM.
A14 Up for a7K transfer.
A13 Down
To begin transfer from the PROM 1K higher
A12 Down
A11 Up in memory
than the Bytemover program.
A10 Down
All down for storage to begin at location
A9 Down
A8 Down zero in RAM.
5. Push
the run switch. In less than one second BASIC will be
loaded into
RAM (it sure beats paper tape!). Now raise the
stop switch.
Example 4: If you
do not have Bytemover in PROM, you can
program aPROM with Bytemover that is stored in RAM. The
Bytemover software (see listing) must first be loaded into
RAM
beginning at location zero in memory. The Bytemover software
can
then be burned into aPROM using the following procedure:
1. Raise the reset switch.
2. Depress
the unprotect switch (on the Altair front panel).
3. Insert an erased PROM
into PROM location zero.
4. Examine location 000 240 in memory.
5. Raise
the program power switch on the Bytesaver board.
6.
Set the sense switches with A15. A14 and A13 up. .
7. Push
the run switch. When light A9 stops blinking, the pro- ~
gramming is complete. The INTE light will be on.
8. Turn off PROM program power by depressing the switch on
the Bytesaver.
•
'.

I I
Unprotect position (PROM can be programmed).
Protect
Switch
Protect position (PROM cannot be programmed).
I
¢:J Increasing memory address.
FIGURE 3: Bytesaver phsicallayout.
I
BYTEMOVER SOFTWARE
-
- -~ ... ~ ~--- ....... --- --
- -- --
- ---------~----
- -- ------ -------
----- ------- ---- ._-
-------------------------..-..;= =' ~ =:~ ===-~~
Erasing PROMS: The 2704 and 2708 PROMs are erased by
shining intense U.V. light through their quartz windows. One
such U.V. source is available for $125 from Prometrics, 5345
North Kedzie Av., Chicago, IL 60625.
B~temover 3.~ Oetal Listing
061 000
000 301 321 0:56 311
363 34:5 34:5 000 000 000 061
004 000
31:5 000 000 061 002
000
341
061
004
000 325 30:5 371
016 000
131
1:51 _:?33
377
127
346 007 007 007
107 172 346 070
017
000
147 071
056 000 172 353 346
200 017 017
306
055
041 000 000 157 071
351
371 041 013 000
071 353 371 353
021
000 000 073
361 002
003 023
172 346 004 007 007
000 205 157
351
000
000
076
126 205 157
351
000 151 174 140 371
147 056 153
001
000 000 073
361 022
023 003
170 376 374
077
037
037
346
100 056 175 205 157 351
056 153 170
346 004 007 007
007 205 157
351 000 000 000
174 041 000
374 071
371 041
000' 374
031
353 147 056
153 170 346
370 306-010
107
351
333 377
107 346 340 036 000
113 127 170 346 037 107 147 056
140
35i~66 032 157
::p3 377 346
100 017 017 205 157 351 174
041 000
374 071
371 056 315
147 351 000 000 000 000 373 351
174 041 000
374 031
353 056 361 147 001
000 000 351
000 326
220 157 172
306
004 127 376 070 077 076 000
037
205
157 351 000 000 373
351 351
''-'
351 073
361 353 276 353 027 346
001
057 074
205 157 073 073
361
057 353
206 353 306 007 077 027
346 001 057 074 205 157
003 023
170 346 004 057 074
205
157
351 000 000
000
000 000 000 000 000
..
5

~-=.~--- - ---..=.~
...:B::..;y=--T::..:E::.M=O:....:V:....:E::.:R::....:.;A:.:S:..::S:::E:.:.M:=:B::.L=y....:L::.:I:.:S:...:T:...:I~N:...:G::..-:=;= -==- __: "= n _ -d ..::...
0000 0000
*
BYTEMOVER
<T. M. )
SOFTWARE FOR
,
0000
0001
*
CROMEMCO BK BYTESAVER
(T. M. )
"J
0000 0002
*VERSION
3. I
0000 0003
*SELF-RELOCATING
SOFTWARE LOCATABLE AT ANY
0000 0004
*
1024 BYTE
( I K)
B~UNDARY IN MEMORY
0000 0009
*ROUTINE
TO FIND ONESELF IN MEMORY
0000 0010
SP EGU 6
0000 0019 *DEFINE FIRST 4BYTES IN
MEMORY AS
STACII,
0000 31 00 00 0020
LXI SP,
0
0003 0029 * SAVE FIRST FOUR BYTES IN REGISTERS
0003 CI 0030 POP B
0004
DI
0040 POP D
0005
0049 * REPLACE BYTE o WITH A'RETURN' ,
0005 2E C9 0050
MVI L,
OC9H
J
0007
F3
0051
01
0008 E5 0060 PUSH H
0009 E5
0070 PUSH H
OOOA 00
0080 NOP
OOOB 00
0081 NOP
OOOC 00 0082
NOP
0000 31 04 00 0090
LXI SP. 4
0010 CD 00 00
0100 CALL 0
0013 0101 * ROM LOCATION
NOW IN BYTE 3
0013
31 02 00
0110
LXI SP,
2
0016 EI
0120 POP H
0017 0129 * RETURN BYTES
0-3
0017 31 04 00 0130
LXI SP.4
~
OOIA 05
0140 PUSH 0
OOIB C5
0150 PUSH B
OOIC 0159
* STORE
ROM
LOCATION IN SP
OOIC
F9
0160 SPHL
0010 OE 00
0170
MVI C, 0
OOIF
59
0180
MOV E,C
0020 69
0190 MOV L. C
0021
0199 *INPUT SENSE
SW COMMANDS
0021 DB FF
0200 IN 255
0023 57 0210
MQV D,A
0024 0219 * STRIP RAM ADDRESS
0024 E6 07 0220
ANI 7
0026 07
0230
RLC
0027 07 0240
RLC
0028 0249 *STORE RAM
ADDRESS IN BC
0028 47
0250 MOV B.A
0029 7A
0260 MOV A.D
002A
0269
* STfHP ROM
ADDRESS
002A E6 38
0270 ANI 56
J
002C OF
0280
RRC
0020 00
0290 NOP
,
002E 67
0300 MOV H.A
002F 39
0310 DAD SP
0030 2E 00
0320 MVI
L, 0
0032 7A
0330
MOV A,D
0033 EB
0340 XCHG
0034 0341
* ADDRESS OF ROM BEING PROCESSED IN DE
0034 0349
* BRANCH TO TRANSFER DR PROGRAM ROUTINE
6

-=B:..:Y:...:T:..:E::.:M=O~V-=E::R::..A:.=::::S.::S=E::.:M::B:::L::.:Y=-=L:=.'=.S.=.T::.:'N:..:..::G--.:=~- : =- ~ :::: = .: :: == ..: -=-
ANI 128
RRC
RRC
ADI 45
LXI H. 0
MOV L.A
DAD SP
PCHL
* ROUTINE TO TRANSFER ROM TO RAM
SPHL
LX I H. 11
DAD SP
XCHG
SPHL STACK CONTAINS ROM LOCATION
XCHG H&L CONTAIN LOOP ADDRESS
LXI D. 0
*START OF TRANSFER LOOP
* INCREMENT ROM ADDRESS
DCX SP
* MOVE DATA FROM ROM TO RAM
POP 6
STAX B
* INCREMENT RAM ADDRESS
INX B
* INCREMENT BYTE COUNT
INX D
MOV A.D
ANI 4
RLC
RLC
NoP
ADD L
MoV L.A
PCHL
NoP
NoP
JUMP TO OOBI FROM TRANSFER ROUTINE
MVI A. 56H
ADD L
MOV L. A
PCHL
* ROUTINE TO PROGRAM ROM
NDP
* MOVE RAM ADDRESS INTO HL
MOV L,e
MDV A.H
MDV H. B
*MOVE RAM ADDRESS INTO SP
SPHL
MDV H.A
MVI L. 107
* INCREMENT RAM ADDRESS
LXI B. 0
* INCREMENT RAM ADDRESS
DCX SP
* USE STAX AND POP 6(PSW)
0350
0360
0370
0380
0390
0400
0410
0420
0500
0510
0520
0530
0550
0560
0570
0580
0588
0589
0590
0599
0600
0610
0619
0620
0629
0630
0640
0650
0660
0670
0680
0690
0700
0710
0716
0717
0719 *
0720
0725
0730
0740
1000
1010
1019
1020
1030
1040
1049
1050
1060
1070
1079
1080
1089
1090
1098
0034 E6 80
0036 OF
0037 OF
0038 C6 2D
003A 21 00 00
003D 6F
003E 39
003F E9
0040
0040
F9
0041 21 OB 00
0044 39
0045 EB
0046 F9
0047 EB
0048 11 00 00
004B
004B
004B
3B
004C
004C
Fl
004D 02
004E
004E
03
004F
004F
13
0050 7A
0051 E6 04
0053 07
0054 07
0055 00
0056 85
0057 6F
0058 E9
0059 00
005A 00
005B
005B
3E 56
005D 85
005E 6F
005F E9
0060
0060
00
0061
0061
69
0062 7C
0063 60
0064
0064 F9
0065 67
0066 2E 6B
0068
0068
01 00 00
006B
006B
3B
006C
7

I
- .:._- - --- - --- --
..:B:..:Y:...:T:..:E::.:M=O~V..:E::B::....::A:.:S:..::S:..::E:::M.:.:B::.:L=.Y=---=L::':..::S:...:T:..::'.:.:N:...:G=----a-~- :- --==; =- === ~=-
•
•
•
VERSION
OVERFLOW
ROM ADDRESS
I
BYTE COUNT
TO 1090 UNLESS
TO 1380 FOR
SUBTRACTION
FOR QUITS
* TO MOVE DATA FROM ROM TO RAM
POP 6
STAX D
*INCREMENT
INX D
* INCREMENT
INX B
*BSTORES TWO CONSTANTS
*# COMPLETE PASSES &IN ROM CNT
MOV A.B
*#PASSES = 32 ?
CPI 252
CMC
RAR
RAR
*SET 64 TO 0 FOR TWO MINUTE TIMER
ANI 64
*A=64 IF COMPLETED 32 PASSES
MVI L. 7DH
ADD L
MOV L.A
PCHL
MVI L. 6BH
MOV A.B
ANI 4
*A=4 IF END OF 1024 BYTE PASS
RLC
RLC
RLC
ADD L
MOV L. A
* GO BACK
* THEN GO
* ADDRESS
* DR 2135
PCHL
NOP
NOP
NOP
* ANOTHER PROGRAM PASS TO BE DONE
*ADJUST ROM AND RAM ADDRESSES
MOV A.H
LXI H; 64512
* SUBTRACT 1024 FROM ROM ADDRESS
DAD SP
SPHL
LXI
H. 64512
* SUBTRACT 1024 FROM RAM ADDRESS
DAD D
XCHG
MOV H.A
MVI L. 107
MOV A,B
ANI 248
* INCREMENT PASS CONTER BY ONE
ADI 8
1099
1100
1110
1119
1120
1129
1130
1138
1139
1140
1149
!l50
1160
1170
1180
1198
1200
1201
1205
1210
1220
1225
1226
1230
1240
1241
1250
1260
1270
1280
1290
1291
1292
1293
1294
1300
1350
1360
1370
1378
1379
1380
1390
1399
1400
1410
1420
1429
1430
1440
1450
1460
1470
1480
1489
1490
006C
006C
Fl
006D 12
006E
DObE 13
006F
006F
03
0070
0070
0070
78
0071
0071
FE FC
0073 3F
0074 IF
0075 IF
0076
0076
E6 40
0078
0078
2E 7D
007A 85
007B 6F
007C E9
007D 2E 6B
007F 78
0080 E6 04
0082
0082
07
0083 07
0084 07
0085 85
0086 6F
0087
0087
0087
0087
0087
E9
0088 00
0089 00
008A 00
008B
008B
008B
7C
008C 21 00 FC
008F
008F
39
0090 F9
0091 21 00 FC
0094
0094 19
0095 EB
0096 67
0097 2E 6B
0099 78
009A E6 F8
009C
009C
C6 08
8

--'-
BYTEMOVER ASSEMBLY LISTING
=-;=-:- ===~:::.:
009E 47
1495 MOV B,A
009F
1499
* GO BACK TO 1090
.'V
009F E9
1500
PCHL
OOAO
2000
*ROUTINE
TO LOAD BYEMOVER
INTO ROM
OOAO DB FF
2010 IN 255
00A2 47
2020
MOV B.A
00A3 E6 EO
2030
ANI 224
00A5 IE 00
2040 MVI
E. 0
00A7 4B
2050 MOV C.E
00A8 57
2060 MOV D.A
00A9 78
2070 MOV A.B
IOOAA E6
IF
2080 ANI 31
OOAC 47
2090 MOV B.A
I
OOAD 67
2100 MOV H.A
OOAE 2E 60
2110 MVI L. 96
OOBO
E9
2120 PCHL
OOBI
2121
* CHECK FOR 7K TRANSFER OF ROM TO RAM
OOBI C6 lA
2122 ADI lAH
00B3 6F
2123 MOV L.A
00B4 DB FF
2124 IN 255
00B6
E6 40
2125 ANI 64
00B8
OF
2126 RRC
00B9 OF
2127 RRC
OOBA
85
2128 ADD L
OOBe 6F
2129 MOV L. A
ooec E9
2130 PCHL
OOeD
2133
* PROGRAMMER VERIFICATION
ROUTINE
OOeD
2134
* PART
1
OOeD 7C
2135 MOV A.H
OOeE 21 00
FC
2145 LXI H.
64512
OOCI
39
2155
DAD SP
00C2 F9
2165 SPHL
00C3 2E CD
2175 MVI L.
OCDH
00C5 67
2185 MOV H.A
00C6
E9
2195 PCHL
00C7 00
2205 NOP
00C8 00
2210 NOP
00C9 00
2215 NOP
OOCA 00
2220 NOP
OOCB
2229
*ROM
TO RAM
TRANSFER STOP ROUTINE
ooce Fe
2230 EI
OOCC E9
2240 PCHL
OOCD
2248
* PROGRAMMER VERIFICATION ROUTINE
OOCD
2249
* PART 2
OOCD
7C
2250
MOV A.H
OOCE 21 00 FC
2260 LXI H.64512
0001 19
2270 DAD 0
0002 Ee
2280 XCHG
0003 2E Fl
2290 MVI L. OFIH
0005 67
2300 MOV H.A
0006 01
00 00
2310 LXI e.
0
0009
E9
2320 PCHL
OODA 00
2625 NOP
OODe
2629
* 7K
TRANSFER COMPLETI ON CHECK
OODe 06 90
2630 SUI 90H
0000 6F
2640 MOV L.A
9

--'-
BYTEMOVER ASSEMBLY LISTING
-------- ---- --
5-= === -:-- ~--
- ----------
OODE 7A
2650 MOV
A,D
OODF C6 04
2660 ADI 4
00E1 57
2670 MOV
D,A
00E2 FE
38 2680 CPI 56
00E4 3F 2685 CMC
00E5 3E 00 2690 MVI
A,
0
00E7 IF
2700 RAR
00E8 85 2710
ADD L
00E9 6F 2720 MOV L,A
OOEA E9
2730 PCHL
OOEB 2879
* ROM
PROGRAMMER
STOP ROUTINE
OOEB 00
2880 NOP
OOEC 00
2881 NOP
•
OOED FB
2885 EI
OOEE E9
2890 PCHL
OOEF E9 2900 PCHL
OOFO E9 2906
PCHL
OOFl 2918
* PROGRAMMER
VERIFICATION ROUTINE
00F1 2919
*PART 3
00F1 3B
2920 DCX SP
00F2 F1
2930 PDP 6
00F3 EB 2940
XCHG
00F4 2949
* COMPARE
FOR GREATER
00F4 BE 2950 CMP M
00F5
EB 2960 XCHG
00F6 17 2970 RAL
00F7 E6 01
3000 ANI 1
00F9 2F 3010
CMA
OOFA 3C 3011 INR A
OOFB 85
3015 ADD L
OOFC
6F 3020 MOV LA
OOFD 3B 3030
DCX SP
OOFE 3B
3040 DCX SP •
OOFF
3050
* COMPARE
FOR LESSER
OOFF F1
3055 PDP 6
0100 2F 3056 CMA
0101 EB
3058 XCHG
0102 86 3059 ADD M
0103 EB
3060 XCHG
0104 C6 07
3061
ADI A. 1
0106 3F
3065 CMC
0107 17
3070 RAL
0108 E6 01
3090 ANI 1
010A 2F
3100 CMA
010B 3C
3101 INR
A
010C 85
3105 AOD L
010D 6F 3110 MOV LA
010E 03 3130 INX B
010F 13 3140 INX D
0110 78
3150 MOV
A, B
0111 E6 04
3180 ANI 4
0113 2F
3190 CMA
0114 3C
3191
INR
A
~
0115 85
3195 ADD L
0116 6F
3200 MDV L. A
0117 E9 3210 PCHL
10

2708-2704 PROM DATA
-
=: -.:.:.-=.. ~-- - -- - -=-~
=--=====.=====.:=-
-------------------------------- ..... ;;;;::: - ~ --- ~ ~ ~ ...... ~ ~
BLOCK DIAGRAM
DATA OUTPUT
0, .Os
I
-
-
CsIWE-
AO·Ag
ADDRESS
INPUTS
CHIP SELECT
LOGIC OUTPUT BUFFERS
Y
DECODER YGATING
.
X
64 X128
DECODER
ROM ARRAY
IPIN NAMES
ADDRESS INPUTS
DATA OUTPUTS
CHIP SELECTIWRITE ENABLE INPUT
READ OPERATION
DC €:I Operating Charaeteristies
TA = o°c to 70°C, Vee = +5V ±5%, Voo = +12V ±5%, VBB = -5V ±5%, Vss = OV, Unless Otherwise Noted.
Symbol Parameter Min. Typ.l1] Max.
Unit
Conditions
III
Address and Chip Select Input Load Current 10
fJA
VIN =5.25V
ILO
Output Leakage Current 10
fJA
V
OUT
=5.25V, CS/WE =5V
100
Voo Supply Current 50
65 rnA Worst
Case Supply Currents:
lee Vee Supply Current 610 rnA
All Inputs High
IB
BV
BB
Supply Current 30 45 rnA CS/WE =5V; TA = O°C
V
1L
Input Low Voltage Vss 0.65 V
V1H
Input High Voltage 3.0 Vee+1 V
VOL
Output Low Voltage 0.45 V
IOL =1.6rnA
VOH1
Output High Voltage 3.7 V
IOH =-100fJA
VOH2
Output High Voltage 2.4 V
·IOH = -lrnA
Po Power Dissipation 800
rnW TA =70°C
NOTES: 1. Typical values are for TA =250eand nominal supply voltages.
2. The program input (Pin 18) may be tied to VSS or Vee during the read mode.
11

2708-2704 PROM DATA
I
II
'I
Ii
I
!
i
--- ... ~~-- -- - --
- -- -- --
- ------~----
=--== ====== ===.5.:::=
--------------------------------....;::;:;:::' ---- - ~ --- ~ ~
Waveforms
(Logic levels and timing reference levels same as in the Read Mode unless noted otherwise.)
Program Mode
CS/WE = +12V
ADDRESS 0
I----------------ONE PROGRAM LOOP ------------ --- 1
x
'-------_w-
. ~DDRESS 1023 A.....-
26V
ADDRESS
PROGRAM
PULSE
OV------...II
""" '
Read/Program/Read Transitions
ADDRESS
CSIWE
o
26V
PROGRAM
PULSE
0--+---------'1
DATA
o,-Os
DATA OUT
VALID
I--
ilOS
DATA IN
VALID
DATA IN
VALID
DATA OUT
VALID
12

2708-2704 PROM DATA
-
----....-..._-- ---- --
- -- -- --
=-===-==-====~=
-------------------------------- ......... ;::::- ----- ~ --- ~ ~
AC Charaeteristies
TA = O°C to 70°C, V
CC
= +5V ±5%, VO
O=
+12V ±5%. VBB = -5V ±5%, VSS =OV. Unless Otherwise Noted.
Symbol Parameter
Min.
Typ.
Max. Unit
tACC Address
to Output Delay 280 450
ns
tco
Chip Select to Output Delay 120
ns
tOF Chip De-Select
to Output Float
0120 ns
tOH Address
to Output Hold 0
ns
Capacitance!1] TA=25°C. f= 1 MHz
Symbol Parameter Typ. Max. Unit
Conditions
CIN
I nput Capacitance 46pF VIN=OV
COUT
Output Capacitance 812 pF VOUT=OV
Waveforms
Note 1. This parameter is periodically sampled and not 100% tested.
ADDRESS -----X-----------------X----------
(Nominal supply voltages unless otherwise noted):
100
ALL POSSIBLE OPERATING
CONDITIONS:
Vee =5.25V
VOO =12.6V
V
BB
' -5.25V
RANGE OF SUPPLY CURRENTS
VS. TEMPERATURE
Or:::::::::·:···· ~~~
o20 40 60 80
80
,----,-----,----,------,-----,
C
E
~
2
w
a::
a::
::l
CJ
>
..J
...
...
::l
CIl
500
400300200
ACCESS TIME
VS. LOAD CAPACITANCE
100
TA• 2~OC
---
-
~
~
-
oo
400
100
300
~
-:, 200
u
.....
1.0.8
.6
--SPEC
Typieal Charaeteristies
I I
1 1--'oH-1
i \ ) :
I \,;,. -J. I 1
I ~ teo ------I II
,_t
OF _
1-010>----- tACC .. I I
1l1!i~~~Jii:i.;~ JEal
.4
DATA
OUT
C.S.fWE
OUTPUT SINK CURRENT
VS. OUTPUT VOLTAGE
.2
10
V
CC
=4.75V
8
TA=O°c
TA'25°C
6TA=70°C
C
E
1>
4
VOL (VQLTS) CL
(pF)
13

Z708-Z704 PROM DATA
ACCESS TIME VS. TEMPERATURE
MAXIMUM JUNCTION TEMPERATURE
VS. AMBIENT TEMPERATURE
1TTL LOAD + 1JPF
.---
---
.----
-
--
500
400
300
200
100
o
-20 o
20 40 60 80
150,-----r----r----r----,
100 1----cJ....-'=----j-----j-----1
501----j-----j-----j-----1
O'-- L- -'-- L-----J
o20 40 60 70
PROGRAMMING OPERATION
Deseription
Initially, and after each erasure, all bits of the 2708/2704 are in the "1" state (Output High). Information is introduced by select-
ively programming
"0" into the desired bit locations.
The circuit is set up for programming operation by raising the CS/WE input (Pin 20) to +12V. The word address is selected in the
same manner as in the read mode. Data to be programmed are presented, 8-bits in parallel, to the data output lines (0
1
-08).
Logic levels for address and data lines and the supply voltages are the same as for the read mode. After address and data set up
one program pulse (Vp) per address is applied to the program input (Pin 18). One pass through all addresses to be programmed is
defined as aprogram loop. The number of loops (N) required is a function of the program pulse width {tpw) according to
N x tpw ~ 100 ms.
For program verification, program loops may be alternated as shown on page 12.
Program Charaeteristies
TA =25°C, Vcc =+5V ±5%, Voo =+12V ±5%, V
ss
= -5V ±5%, Vss = OV, CS/WE =+12V, Unless Otherwise Noted.
Symbol
Parameter Min. Typ. Max. Units
tAS Address
Setup Time 10
IJ.s
tcss
CS/WE Setup Time 10
IJ.s
tos
Data Setup Time 10
IJ.s
tAH
Address Hold Time 1
IJ.s
tCH
CS/WE Hold Time .5
IJ.s
tOH
Data Hold Time
1
IJ.s
tOF Chip Deselect
to Output Float Delay 0 120
ns
tOPR
Program To Read Delay
10
IJ.s
tpw Program Pulse Width .1 1.0 ms
tPR Program Pulse Rise
Time
.5 2.0
IJ.s
tpF Program Pulse Fall Time .5
2.0
IJ.s
Ip
Programming Current 10 20 mA
Vp
Program Pulse Amplitude
25
27 V
14
This manual produced by Laurel Publications [phone].

•
-
, --./
,
Warrant31
Your factory-built Bytesaver is warranted against defects in materials
and workmanship for aperiod
of 90 days from the date of delivery.
We will repair or replace products that prove to be defective during
the warranty period provided that they are returned to Cromemco.
No other warranty is expressed or implied. We are not liable for
consequential damages.
Should your factory-built Bytesaver fail after the warranty period it
will
be repaired, provided that it is returned to Cromemco, for a
fixed service fee.
We reserve the right to refuse to repair any product
that in our opinion has been subject to abnormal electrical or
mechanical abuse. The service fee is currently $35 and is subject
to change.
Your assembled Bytesaver kit will be repaired, provided
that it is re-
turned to Cromemco, for afixed service fee. We reserve the right to
refuse repair of any kit that in our opinion has not been assembled
in aworkmanlike manner or has been subject to abnormal electrical
or mechanical abuse. Payment of the service fee must accompany
the returned merchandise. The service fee is currently $35 and is
subject to change.

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