Posted by: Admin
CF for Apple II, etc - 11/07/15 05:00 AM
Prototype Hardware for older v1.x cards
My first prototype used no discrete 74HCTxxx series parts, all logic was in the CPLD. Due to several unrelated problems with construction and the consumption of all PLD resources, I decided to build a second prototype with using some HCT parts, this time paying more attention to power distribution. I still believe it would be easy to eliminate the discrete 74HCT series parts if you used a larger PLD, like the EPM70128S. Although it might not be very cost effective.
Here is the schematic I developed AFTER completing my prototype. That means this schematic has not been tested. If you decide to build this project from scratch, you should use the schematic from the production board. If you just want a quick look at the schematic click here to view a 640kB jpeg image of the schematic.
1 - SanDisk CompactFlash 64Meg or 32Meg
1 - CompactFlash to IDE conversion board - Adtron SDDA-03 available from EMJ Embedded
1 - ISA bus prototype board (trimmed to fit into the apple bus) Jameco part #21531
1 - 44pin PLCC socket. Jameco part #71618
1 - 44pin PLCC wire-wrap socket. (http://smt-adapter.com/ - part #44PG-W or similar)
1 - Altera EPM7064SLC44-10F
1 - 27128 EPROM
2 - 74HCT373 transparent latch
2 - 74HCT245 bus transceiver
7 - 22ohm 1/8w resistors
5 - 0.1uf capacitors non-polarized (used for power supply bypass)
3 - 1.0uf capacitors non-polarized (used for power supply bypass)
10 - 30 pin wire wrap SIPP sockets. Jameco part #104053 (there were some leftover)
misc wire wrap tools and wire
My prototype was built on a board made from a PC's ISA bus prototyping card that was modified to fit into the Apple II's bus. These prototyping cards are relatively easy to find. I purchased mine through Jameco Electronics. I did the modifications using a utility knife and a straight edge. To know where to cut I used another Apple Peripheral card as a guide. Just score each side of the board deeply and snap along the score line.
My first prototype used no discrete 74HCTxxx series parts, all logic was in the CPLD. Due to several unrelated problems with construction and the consumption of all PLD resources, I decided to build a second prototype with using some HCT parts, this time paying more attention to power distribution. I still believe it would be easy to eliminate the discrete 74HCT series parts if you used a larger PLD, like the EPM70128S. Although it might not be very cost effective.
Here is the schematic I developed AFTER completing my prototype. That means this schematic has not been tested. If you decide to build this project from scratch, you should use the schematic from the production board. If you just want a quick look at the schematic click here to view a 640kB jpeg image of the schematic.
1 - SanDisk CompactFlash 64Meg or 32Meg
1 - CompactFlash to IDE conversion board - Adtron SDDA-03 available from EMJ Embedded
1 - ISA bus prototype board (trimmed to fit into the apple bus) Jameco part #21531
1 - 44pin PLCC socket. Jameco part #71618
1 - 44pin PLCC wire-wrap socket. (http://smt-adapter.com/ - part #44PG-W or similar)
1 - Altera EPM7064SLC44-10F
1 - 27128 EPROM
2 - 74HCT373 transparent latch
2 - 74HCT245 bus transceiver
7 - 22ohm 1/8w resistors
5 - 0.1uf capacitors non-polarized (used for power supply bypass)
3 - 1.0uf capacitors non-polarized (used for power supply bypass)
10 - 30 pin wire wrap SIPP sockets. Jameco part #104053 (there were some leftover)
misc wire wrap tools and wire
My prototype was built on a board made from a PC's ISA bus prototyping card that was modified to fit into the Apple II's bus. These prototyping cards are relatively easy to find. I purchased mine through Jameco Electronics. I did the modifications using a utility knife and a straight edge. To know where to cut I used another Apple Peripheral card as a guide. Just score each side of the board deeply and snap along the score line.