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Split Intel 8755 documentation out

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README.md
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This is a simple EEPROM programmer and reader that can be assembled using an Arduino and a This is a simple EEPROM programmer and reader that can be assembled using an Arduino and a
few additional parts. The original code was specific to the 28C256 32Kx8 EEPROM, but it few additional parts. The original code was specific to the 28C256 32Kx8 EEPROM, but it
has been extended to also support Intel 8755A EPROMS and some 29C010 Flash. has been extended to also support SST39SF040 Flash, many other EEPROMs and flash, and even
Intel 8755A EPROMS.
See the [documentation pages](https://tomnisbet.github.io/TommyPROM/) for the full
documentation with software, schematics, and troubleshooting tips.
Features include: Features include:
* Simple hardware design that can be assembled on a breadboard. * Simple hardware design that can be assembled on a breadboard.
* ROM images transfers using XMODEM - no special host client needed. * ROM images transfers using XMODEM - no special host client needed.
* Support for fast block EEPROM writes - a 32K EEPROM will program in just a few seconds. * Support for fast block EEPROM writes - a 32K EEPROM will program in just a few seconds.
* Optimized code that supports the timing requirements needed to unlock the 28C series * Optimized code that supports the timing requirements needed to unlock the 28C series
Software Protection Algorithm. [Software Protection Algorithm](docs/28C256-notes).
* Modular software design to easily support other EEPROM and EPROM families. * Modular software design to easily support other EEPROM and EPROM families.
![TommyPROM Nano Hardware](docs/images/TommyPROM-nano.jpg) ![TommyPROM Nano Hardware](docs/_docs/images/TommyPROM-nano.jpg)
See the [documentation pages](https://tomnisbet.github.io/TommyPROM/) for the full documentation
with hardware, software, and troubleshooting tips.
## Further Work
* [ ] Add a new PromDevice class for 27 series EPROMS.
* [x] Additional error checking in the CmdLine code.

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docs/_data/navigation.yml
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url: /docs/pcb url: /docs/pcb
- title: "Adding Chip Families" - title: "Adding Chip Families"
url: /docs/extending url: /docs/extending
- title: "8755A Hardware"
url: /docs/8755A-hardware
- title: "References" - title: "References"
children: children:
- title: "28C256 and SDP" - title: "28C256 and SDP"

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docs/_docs/00-intro.md
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@ -63,10 +63,10 @@ files as well. The default code programs 28C series chips using Arduino Nano har
use this version, just compile and upload it to the Arduino. use this version, just compile and upload it to the Arduino.
**Note well** that this code has been optimized for the Aduino UNO and Nano hardware so **Note well** that this code has been optimized for the Aduino UNO and Nano hardware so
*that it can run quickly enough to meet 28C series chip timing requirements for SDP that it can run quickly enough to meet 28C series chip timing requirements for SDP
*unlocking. To use different Arduino hardware, like the Micro, the board-specific code in unlocking. To use different Arduino hardware, like the Micro, the board-specific code in
*PromDevice.cpp and PromAddressDriver.cpp must be changed to match the port mappings PromDevice.cpp and PromAddressDriver.cpp must be changed to match the port mappings
*between the ATmega chip and the Arduino I/O pins. between the ATmega chip and the Arduino I/O pins.
Because the Arduino has limited code and RAM space available, only one PROM driver is Because the Arduino has limited code and RAM space available, only one PROM driver is
compiled in at a time. To change drivers, uncomment the desired PROM_IS_xx line in compiled in at a time. To change drivers, uncomment the desired PROM_IS_xx line in

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docs/_docs/design-100-hardware.md
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--- ---
title: "Hardware Design" title: "Hardware Design"
permalink: /docs/hardware permalink: /docs/hardware
exerpt: "TommyPROM Arduino EEPROM programmer software design" exerpt: "TommyPROM Arduino EEPROM programmer hardware design"
--- ---
## Basic Hardware Version
The hardware uses an Arduino to write data and to toggle control lines with the The hardware uses an Arduino to write data and to toggle control lines with the
appropriate timing to access the PROM. A pair of 74LS164 serial to parallel shift appropriate timing to access the PROM. A pair of 74LS164 serial-to-parallel shift
registers latch the address lines. Use of the shift registers allows the Arduino to registers latch the address lines. Use of the shift registers allows the Arduino to
control up to 16 address lines using only 3 output ports. This design will read and control up to 16 address lines using only 3 output ports. This design will read and
program the 28C series chips and can read most other parallel ROM chip families. program the 28C series chips and can read most other parallel ROM chip families.
@ -100,20 +98,3 @@ down to D2..D9. Most of the ROM and shift register control lines move over to t
pins. The upper shift register is controlled directly from the Arduino instead of being pins. The upper shift register is controlled directly from the Arduino instead of being
connected to the overflow of the lower shift register. All of the connections are in the connected to the overflow of the lower shift register. All of the connections are in the
chart in the section above. chart in the section above.
## Intel 8755A Hardware Version
The Intel 8755A uses a multiplexed data and address bus, plus 3 additional address lines.
Most Arduino hardware has enough pins to support this directly, so no additional hardware
is needed for addressing. An Arduino pin is also used to drive the ALE latch pin.
The 8755A requires the Vdd pin to be be switched between 5V and 25V during the programming
of each byte. A simple transistor circuit is used for this. No voltage regulator circuit
is present here for the programming voltage. Because this is designed as a quickly
assembled hardware design, a triple output bench supply was used to provide the 25.5V,
5.5V and 5V outputs.
[![TommyPROM Nano Schematic](images/TommyPROM-8755A-sch.png)](images/TommyPROM-8755A-sch.png)
Eagle-format schematics can be downloaded from the
[hardware project page](https://github.com/TomNisbet/TommyPROM/tree/master/hardware).

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docs/_docs/design-700-8755A-hardware.md Normal file
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---
title: "8755A Hardware Design"
permalink: /docs/8755A-hardware
exerpt: "TommyPROM Arduino programmer for the Intel 8755A"
---
A special version of the TommyPROM hardware was developed to support the Intel 8755A
EPROM with IO chip. This is a 2Kx8 UV EPROM with additional I/O ports.
The Intel 8355 is a one-time programmable version of the 8755A. This design can be used
to read the 8355.
The Intel 8755A uses a multiplexed data and address bus, plus 3 additional address lines.
Most Arduino hardware has enough pins to support this directly, so no shift register
hardware is needed for addressing. An Arduino pin is also used to drive the ALE latch pin.
The 8755A requires the Vdd pin to be be switched between 5V and 25V during the programming
of each byte. A simple transistor circuit is used for this. No voltage regulator circuit
is present here for the programming voltage. Because this is designed as a quickly
assembled hardware design, a triple output bench supply was used to provide the 25.5V,
5.5V and 5V outputs.
[![TommyPROM Nano Schematic](images/TommyPROM-8755A-sch.png)](images/TommyPROM-8755A-sch.png)
Eagle-format schematics can be downloaded from the
[hardware project page](https://github.com/TomNisbet/TommyPROM/tree/master/hardware).