HP9845 communiation with ext. interfaces

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William
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Joined: Thu Jul 27, 2023 5:56 am

HP9845 communiation with ext. interfaces

Post by William »

Hi to all,
I have created detailed schematic diagram of backplane at HP9845B. The backplane has part number 09845-66502. It has four slots for external interfaces. On the board are TTL buffers for inputs- / outputs data. I would like know a communication between the data buffers and CPU.
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HP9845B
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Joined: Mon Sep 23, 2024 6:36 pm

Re: HP9845 communiation with ext. interfaces

Post by HP9845B »

find manual for RTC clock 98035. In this manual you find schematics. First page of the schematic is the interface. This interface is important for you. It comply with the backplane 09845-66502.
How to control your interface:
you need to use standard I/O HP Basic commands. If your interface uses a MCU, the MCU needs to decode the HP Basic commands. The I/O HP Basic commands are described in the I/O programming manual.
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Antonov
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Re: HP9845 communiation with ext. interfaces

Post by Antonov »

I have bought on eBay an 16-bit interface for HP9845B. Unlike, it has a 50-pin cable without connector. What of connector is suitable for that?
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OneDollar
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Joined: Thu Oct 31, 2024 7:34 pm

Re: HP9845 communiation with ext. interfaces

Post by OneDollar »

Use any 50-pin connector as you need. HP used different connectors to match the peripheral.
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