082 Cart Sorter Arrival

We received an 082 card sorter from Chicago, IL. The 082 has been cleaned and adjusted and is sorting cards. While Fred, Gary and Jack worked on building a 1442 interface, Bill worked up changes to the math expression solving software to provide hierarchy of math operators, ie. multiply and divide execute in preference to add and subtract. This change was developed as changes to the existing program which was still in the 1441 memory. Nice feature of magnetic core memory, it remembers what is in memory when the power is turned off. These changes were not tried as the 1442 interface became ready to debug. With the 1442 interface board design complete, Gary built it using a PC AT expansion board, 2 Arduino microprocessors, opto isolators and other components. Gary programmed one Arduino and Jack programmed the other one. Debugging this interface led to having to adjust the card read hardware and due to an early microprogram bug, one read attempt caused all 8000 1441 memory locations to be cleared to blanks! It was as if the reader had read a card that was 8000 long! With problems corrected, we have actually read a card correctly into the 1441 memory, although the 1441 indicated that there was an error. A problem to investigate when we aren't working on our other devices.