30-pin, proprietary Apple 68-pin, and 72-pin SIMMs
- Apple Airport Extender
- Laptop Memory Extender
- Apple Store Wifi Extender
- Apple Memory Extender Wifi
- Apple Extender Routers
A SIMM (single in-line memory module) is a type of memory module containing random-access memory used in computers from the early 1980s to the late 1990s. It differs from a dual in-line memory module (DIMM), the most predominant form of memory module since the late 1990s, in that the contacts on a SIMM are redundant on both sides of the module. SIMMs were standardised under the JEDEC JESD-21C standard. Drama korea dr stranger sub indo.
Apple Three-prong AC Wall Plug Adapter Recall Program April 25, 2019. 13-inch MacBook Pro (non Touch Bar) Solid-State Drive Service Program November 9, 2018. IPhone X Display Module Replacement Program for Touch Issues November 9, 2018. IPhone 8 Logic Board Replacement Program. 1-16 of 800 results for 'apple wireless range extender' NETGEAR WiFi Range Extender EX3700 - Coverage up to 1000 sq.ft. And 15 Devices with AC750 Dual Band Wireless Signal Booster & Repeater (up to 750Mbps Speed), and Compact Wall Plug Design. 3.8 out of 5 stars 33,382. Mac Pro Memory for Model 6.1: Mac Pro Late 2013 4 slots DDR3-1866Mhz. The latest model of the Mac Pro takes DDR3-1866Mhz RAM. The machine has four slots that can take up to 32GB. per slot for. Mac Pro Memory for Model 5.1 12-Core and 6-Core: Mac Pro Mid 2010 8 slot and 4 slot versions DDR3-1333Mhz. If you’d like to upgrade the memory in one of these models, an Apple Authorised Service Provider can help. Before you schedule an appointment, confirm that the specific Apple Authorised Service Provider offers memory upgrade services. Memory in iMac (21.5-inch, Late 2015) and iMac (Retina 4K, 21.5-inch, Late 2015) is not upgradeable.
Most early PC motherboards (8088-based PCs, XTs, and early ATs) used socketed DIP chips for DRAM. As computer memory capacities grew, memory modules were used to save motherboard space and ease memory expansion. Instead of plugging in eight or nine single DIP chips, only one additional memory module was needed to increase the memory of the computer.
History[edit]
SIMMs were invented in 1982 by James J. Parker at Zenith Microcircuits and the first Zenith Microcircuits customer was Wang Laboratories. Wang Laboratories tried to patent it and were granted a patent in April 1987.[1] That patent was later voided when Wang Laboratories sued multiple companies for infringement and it was then publicized that they were the prior invention of Parker at Zenith Microcircuits (the Elk Grove Village, Illinois subsidiary of Zenith Electronics Corporation). The lawsuit was then dropped and the patent was vacated. The original memory modules were built upon ceramic substrates with 64K Hitachi 'flip chip' parts and had pins, i.e. single in-line package (SIP) packaging.[2] There was an 8-bit part and a 9-bit part both at 64K. The pins were the costliest part of the assembly process and Zenith Microcircuits, in conjunction with Wang and Amp, soon developed an easy insertion, pinless connector. 1989 fleetwood southwind service manual. Later the modules were built on ceramic substrates with Fujitsu plastic J-lead chips and still later, they were made on standard PCB material. SIMMs using pins are usually called SIP or SIPP memory modules to distinguish them from the more common modules using edge connectors.
The first variant of SIMMs has 30 pins and provides 8 bits of data (plus a 9th error-detection bit in parity SIMMs). They were used in AT-compatible (286-based, e.g., Wang APC[3]), 386-based, 486-based, Macintosh Plus, Macintosh II, Quadra, Atari STE microcomputers, Wang VS minicomputers and Roland Electronic Samplers.
The second variant of SIMMs has 72 pins and provides 32 bits of data (36 bits in parity and ECC versions). These appeared first in the early 1990s in later models of the IBM PS/2, and later in systems based on the 486, Pentium, Pentium Pro, early Pentium II, and contemporary/competing chips of other brands. By the mid-90s, 72-pin SIMMs had replaced 30-pin SIMMs in new-build computers, and were starting to themselves be replaced by DIMMs.
Free video effects software. Non-IBM PC computers such as UNIX workstations may use proprietary non-standard SIMMs. The Macintosh IIfx uses proprietary non-standard SIMMs with 64 pins.
DRAM technologies used in SIMMs include FPM (Fast Page Mode memory, used in all 30-pin and early 72-pin modules), and the higher-performance EDO DRAM (used in later 72-pin modules).
Due to the differing data bus widths of the memory modules and some processors, sometimes several modules must be installed in identical pairs or in identical groups of four to fill a memory bank. The rule of thumb is a 286, 386SX, 68000 or low-end 68020 / 68030 (e.g. Atari Falcon, Mac LC) system (using a 16 bit wide data bus) would require two 30-pin SIMMs for a memory bank. On 386DX, 486, and full-spec 68020 through 68060 (e.g. Atari TT, Amiga 4000, Mac II) systems (32 bit data bus), either four 30-pin SIMMs or one 72-pin SIMM are required for one memory bank. On Pentium systems (data bus width of 64 bits), two 72-pin SIMMs are required. However, some Pentium systems have support for a 'half bank mode', in which the data bus would be shortened to only 32 bits to allow operation of a single SIMM. Conversely, some 386 and 486 systems use what is known as 'memory interleaving', which requires twice as many SIMMs and effectively doubles the bandwidth.
The earliest SIMM sockets were conventional push-type sockets. These were soon replaced by ZIF sockets in which the SIMM was inserted at an angle, then tilted into an upright position. To remove one, the two metal or plastic clips at each end must be pulled to the side, then the SIMM must be tilted back and pulled out (low-profile sockets reversed this convention somewhat, like SODIMMs - the modules are inserted at a 'high' angle, then pushed down to become more flush with the motherboard). The earlier sockets used plastic retainer clips which were found to break, so steel clips replaced them.
Some SIMMs support presence detect (PD). Connections are made to some of the pins that encode the capacity and speed of the SIMM, so that compatible equipment can detect the properties of the SIMM. PD SIMMs can be used in equipment which does not support PD; the information is ignored. Standard SIMMs can easily be converted to support PD by fitting jumpers, if the SIMMs have solder pads to do so, or by soldering wires on.[4]
30-pin SIMMs[edit]
30-pin SIMM, 256 KB capacity
Two 30-pin SIMM slots on an IBM PS/2 model 50 motherboard
Standard sizes: 256 KB, 1 MB, 4 MB, 16 MB
Apple Airport Extender
30-pin SIMMS have 12 address lines, which can provide a total of 24 address bits. With an 8 bit data width, this leads to an absolute maximum capacity of 16 MB for both parity and non-parity modules (the additional redundancy bit chip usually does not contribute to the usable capacity).
Pin # | Name | Signal Description | Pin # | Name | Signal Description |
---|---|---|---|---|---|
1 | VCC | +5 VDC | 16 | DQ4 | Data 4 |
2 | /CAS | Column Address Strobe | 17 | A8 | Address 8 |
3 | DQ0 | Data 0 | 18 | A9 | Address 9 |
4 | A0 | Address 0 | 19 | A10 | Address 10 |
5 | A1 | Address 1 | 20 | DQ5 | Data 5 |
6 | DQ1 | Data 1 | 21 | /WE | Write Enable |
7 | A2 | Address 2 | 22 | VSS | Ground |
8 | A3 | Address 3 | 23 | DQ6 | Data 6 |
9 | VSS | Ground | 24 | A11 | Address 11 |
10 | DQ2 | Data 2 | 25 | DQ7 | Data 7 |
11 | A4 | Address 4 | 26 | QP* | Data parity out |
12 | A5 | Address 5 | 27 | /RAS | Row Address Strobe |
13 | DQ3 | Data 3 | 28 | /CASP* | Parity Column Address Strobe |
14 | A6 | Address 6 | 29 | DP* | Data parity in |
15 | A7 | Address 7 | 30 | VCC | +5 VDC |
* Pins 26, 28 and 29 are not connected on non-parity SIMMs.
72-pin SIMMs[edit]
72-pin EDO DRAM SIMM
Standard sizes: 1 MB, 2 MB, 4 MB, 8 MB, 16 MB, 32 MB, 64 MB, 128 MB (the standard also defines 3.3 V modules with additional address lines and up to 2 GB)
With 12 address lines, which can provide a total of 24 address bits, two ranks of chips, and 32 bit data output, the absolute maximum capacity is 227 = 128 MB.
Pin # | Name | Signal Description | Pin # | Name | Signal Description |
---|---|---|---|---|---|
1 | VSS | Ground | 37 | MDP1* | Data Parity 1 (MD8.15) |
2 | MD0 | Data 0 | 38 | MDP3* | Data Parity 3 (MD24.31) |
3 | MD16 | Data 16 | 39 | VSS | Ground |
4 | MD1 | Data 1 | 40 | /CAS0 | Column Address Strobe 0 |
5 | MD17 | Data 17 | 41 | /CAS2 | Column Address Strobe 2 |
6 | MD2 | Data 2 | 42 | /CAS3 | Column Address Strobe 3 |
7 | MD18 | Data 18 | 43 | /CAS1 | Column Address Strobe 1 |
8 | MD3 | Data 3 | 44 | /RAS0 | Row Address Strobe 0 |
9 | MD19 | Data 19 | 45 | /RAS1† | Row Address Strobe 1 |
10 | VCC | +5 VDC | 46 | NC | Not Connected |
11 | NU [PD5#] | Not Used [Presence Detect 5 (3v3)] | 47 | /WE | Read/Write Enable |
12 | MA0 | Address 0 | 48 | NC [/ECC#] | Not Connected [ECC presence (if grounded) (3v3)] |
13 | MA1 | Address 1 | 49 | MD8 | Data 8 |
14 | MA2 | Address 2 | 50 | MD24 | Data 24 |
15 | MA3 | Address 3 | 51 | MD9 | Data 9 |
16 | MA4 | Address 4 | 52 | MD25 | Data 25 |
17 | MA5 | Address 5 | 53 | MD10 | Data 10 |
18 | MA6 | Address 6 | 54 | MD26 | Data 26 |
19 | MA10 | Address 10 | 55 | MD11 | Data 11 |
20 | MD4 | Data 4 | 56 | MD27 | Data 27 |
21 | MD20 | Data 20 | 57 | MD12 | Data 12 |
22 | MD5 | Data 5 | 58 | MD28 | Data 28 |
23 | MD21 | Data 21 | 59 | VCC | +5 VDC |
24 | MD6 | Data 6 | 60 | MD29 | Data 29 |
25 | MD22 | Data 22 | 61 | MD13 | Data 13 |
26 | MD7 | Data 7 | 62 | MD30 | Data 30 |
27 | MD23 | Data 23 | 63 | MD14 | Data 14 |
28 | MA7 | Address 7 | 64 | MD31 | Data 31 |
29 | MA11 | Address 11 | 65 | MD15 | Data 15 |
30 | VCC | +5 VDC | 66 | NC [/EDO#] | Not Connected [EDO presence (if grounded) (3v3)] |
31 | MA8 | Address 8 | 67 | PD1x | Presence Detect 1 |
32 | MA9 | Address 9 | 68 | PD2x | Presence Detect 2 |
33 | /RAS3† | Row Address Strobe 3 | 69 | PD3x | Presence Detect 3 |
34 | /RAS2 | Row Address Strobe 2 | 70 | PD4x | Presence Detect 4 |
35 | MDP2* | Data Parity 2 (MD16.23) | 71 | NC [PD (ref)#] | Not Connected [Presence Detect (ref) (3v3)] |
36 | MDP0* | Data Parity 0 (MD0.7) | 72 | VSS | Ground |
* Pins 35, 36, 37 and 38 are not connected on non-parity SIMMs.[5]
†/RAS1 and /RAS3 are only used on two-rank SIMMS: 2, 8, 32, and 128 MB.
# These lines are only defined on 3.3V modules.
x Presence Detect signals are detailed in JEDEC Standard.
Proprietary SIMMs[edit]
GVP 64-pin[edit]
Several CPU cards from Great Valley Products for the CommodoreAmiga used special 64-pin SIMMs (32 bits wide, 1, 4 or 16 MB, 60 ns).
Apple 64-pin[edit]
Dual-ported 64-pin SIMMs were used in AppleMacintosh IIfx computers to allow overlapping read/write cycles (1, 4, 8, 16 MB, 80 ns).[6][7]
Pin # | Name | Signal Description | Pin # | Name | Signal Description |
---|---|---|---|---|---|
1 | GND | Ground | 33 | Q4 | Data output bus, bit 4 |
2 | NC | Not connected | 34 | /W4 | Write-enable input for RAM IC 4 |
3 | +5V | +5 volts | 35 | A8 | Address bus, bit 8 |
4 | +5V | +5 volts | 36 | NC | Not connected |
5 | /CAS | Column address strobe | 37 | A9 | Address bus, bit 9 |
6 | D0 | Data input bus, bit 0 | 38 | A10 | Address bus, bit 10 |
7 | Q0 | Data output bus, bit 0 | 39 | A11 | Address bus, bit 11 |
8 | /W0 | Write-enable input for RAM IC 0 | 40 | D5 | Data input bus, bit 5 |
9 | A0 | Address bus, bit 0 | 41 | Q5 | Data output bus, bit 5 |
10 | NC | Not connected | 42 | /W5 | Write-enable input for RAM IC 5 |
11 | A1 | Address bus, bit 1 | 43 | NC | Not connected |
12 | D1 | Data input bus, bit 1 | 44 | NC | Not connected |
13 | Q1 | Data output bus, bit 1 | 45 | GND | Ground |
14 | /W1 | Write-enable input for RAM IC 1 | 46 | D6 | Data input bus, bit 6 |
15 | A2 | Address bus, bit 2 | 47 | Q6 | Data output bus, bit 6 |
16 | NC | Not connected | 48 | /W6 | Write-enable input for RAM IC 6 |
17 | A3 | Address bus, bit 3 | 49 | NC | Not connected |
18 | GND | Ground | 50 | D7 | Data input bus, bit 7 |
19 | GND | Ground | 51 | Q7 | Data output bus, bit 7 |
20 | D2 | Data input bus, bit 2 | 52 | /W7 | Write-enable input for RAM IC 7 |
21 | Q2 | Data output bus, bit 2 | 53 | /QB | Reserved (parity) |
22 | /W2 | Write-enable input for RAM IC 2 | 54 | NC | Not connected |
23 | A4 | Address bus, bit 4 | 55 | /RAS | Row address strobe |
24 | NC | Not connected | 56 | NC | Not connected |
25 | A5 | Address bus, bit 5 | 57 | NC | Not connected |
26 | D3 | Data input bus, bit 3 | 58 | Q | Parity-check output |
27 | Q3 | Data output bus, bit 3 | 59 | /WWP | Write wrong parity |
28 | /W3 | Write-enable input for RAM IC 3 | 60 | PDCI | Parity daisy-chain input |
29 | A6 | Address bus, bit 6 | 61 | +5V | +5 volts |
30 | NC | Not connected | 62 | +5V | +5 volts |
31 | A7 | Address bus, bit 7 | 63 | PDCO | Parity daisy-chain output |
32 | D4 | Data input bus, bit 4 | 64 | GND | Ground |
HP LaserJet[edit]
72-pin SIMMs with non-standardPresence Detect (PD) connections.
![Apple airport extender Apple airport extender](https://www.jake-morgan.com/wp-content/uploads/2013/07/RAMFactor.jpeg)
See also[edit]
- Dual in-line package (DIP)
- Single in-line package (SIP)
- Zig-zag in-line package (ZIP)
- Dual in-line memory module (DIMM)
References[edit]
- ^U.S. Patent 4,656,605 - Single in-line memory module
- ^Clayton, James E. (1983). Low-cost, high-density memory packaging: A 64K X 9 DRAM SIP module, The International journal for hybrid microelectronics.
- ^Wang Plays A Strong PC-Compatible Hand, PC Magazine, October 1, 1985
- ^Making Standard SIMMs Work – Memory Upgrade on the HP LaserJet 6MP/5MP Article on fitting jumpers to add Presence Detect to standard SIMMs
- ^JEDEC Standard No. 21-C, Section 4.4.2 '72 pin SIMM DRAM Module Family'
- ^Macintosh IIfx
- ^Apple Computer, Inc. (1990). Guide to the Macintosh Family Hardware (2nd ed.). Addison-Wesley, Inc. p. 230.
- ^Apple Computer, Inc. (1990). Guide to the Macintosh Family Hardware (2nd ed.). Addison-Wesley, Inc. pp. 214–222.
External links[edit]
Wikimedia Commons has media related to SIMM. |
Laptop Memory Extender
Retrieved from 'https://en.wikipedia.org/w/index.php?title=SIMM&oldid=986099683'
Let's face it, 16 GB of iPhone storage just doesn't cut it anymore.
With all the photos, videos, apps and music that we load onto our phones, filling up 16 GB doesn't take much effort.
The two ways people generally combat the storage crunch -- deleting or splurging -- are unsavory choices. Constantly deleting all those files is a pain, and paying $100 for an extra 48 GB is an enormous ripoff.
Unfortunately, the iPhone doesn't have expandable storage like some other smartphones. But there are ways to expand your iPhone's storage without breaking the bank or deleting everything.
1) Plug in a flash drive. Even though you can't expand your iPhone's internal storage, you can grow its external storage. Flash storage works for your iPhone just like adding an external hard drive for your PC -- except this one comes along for the ride wherever your iPhone goes.
Flash storage devices like the $60 Leef iBridge plug right into your Lightning port and instantly boost your phone's storage. The iBridge has a J-shape so it bends around your iPhone, but it's a lot of money to spend on just another 16 GB of storage. There are plenty of other options, including a $42 SanDisk iExpand, which has 32 GB of storage.
Apple Store Wifi Extender
Macbook air no storage space. Mophie makes a combination battery and 32 GB external storage case called the Space Pack. It costs $149, but you were probably going to throw down some money on a case anyway.
And the $38 TFZ i-Flash Drive lets you add as much storage as you want with an SD card. (If you don't have any lying around from your old digital camera, you can buy a 128 GB micro SD card on Amazon for about $60).
2) Keep a wireless hard drive in your pocket. If you're not keen on wires or having something constantly plugged into your phone, there are wireless storage options too.
By connecting them to the same Wi-Fi network, your iPhone can sync with a wireless storage device in your pocket or purse. With a corresponding app, you can set your phone to automatically store stuff on the wireless drive instead of storing it internally.
Apple Memory Extender Wifi
The $36 RAVPower Filehub is a great example. You can stick any flash drive or SD card into it. And if you plug it into your phone, it doubles as an external battery. The $47 SanDisk Connect comes with 32 GB of on-board storage (no need for an SD card).
3) Keep your files at home. If you need a lot of extra storage, you can build your own personal cloud. The $159 Western Digital MyCloud network storage device lets you store up to 4 terabytes (that's 4,000 GB) worth of files.
You keep the MyCloud at home, but you can access the files from wherever you're using the corresponding app. As an added bonus, you can also use the MyCloud to back up all the files from your home PC or Mac.
4) Use the cloud. Why store your files on your own hard drive when you can store them on someone else's servers? You can use DropBox, Amazon Cloud Drive, Google Drive, Microsoft(MSFT) OneDrive or Apple(AAPL) iCloud to manage your files in the cloud. Depending on how much you store, you might have to pay a monthly subscription fee.
Google(GOOGL) Photos will give you free, unlimited photo storage, albeit in a somewhat smaller file size. And Google Play Music Manager and Amazon(AMZN) Cloud Drive will allow you to upload your entire music library to the cloud, and stream it to your phone.
5) Clean your phone. If you use apps such as DU Speedbooster for Android or PhoneClean for iPhones, you can clear out unnecessary files that accumulate on your phone. But you'll only reclaim so much space -- a couple gigabytes at most.
If that's all you need, cleaning your phone is a free and easy solution.
Apple Extender Routers
CNNMoney (New York) First published February 17, 2016: 10:38 AM ET