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Last modified by Max on 2025/03/02 15:18
From version 2.13
edited by Max
on 2025/02/25 12:51
Change comment: (Autosaved)
To version 2.14
edited by Max
on 2025/02/25 12:56
Change comment: (Autosaved)

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... ... @@ -375,11 +375,13 @@
375 375  
376 376  
377 377  There are PDP-11 operating systems that support such disks - RSX-11, DIAMS, and some others. However, the most common OS - RT-11 - uses a WORD (16 bits) for the block number, and the code 0177777 is used in some places for special purposes and is not suitable as a disk size, so disks with a maximum number of blocks of 0177776, i.e. 65534 blocks (33553408 bytes or 32767 K bytes), can be used for RT-11. Therefore, there are two commands for setting the block number: to set the low-order bits of the block number - code 002 and to set the high-order bits of the block number - code 012. If the block number fits into 16 bits (for RT-11 - always), it is enough to use the command to set the low-order bits of the block number, the high-order bits are cleared. If the number does not fit into 16 digits, then first the lower bits must be output, and then the higher ones. If you try to immediately transmit the higher bits without first transmitting the lower ones, an error is returned. If the transmitted address goes beyond the file-image boundary, an error is also returned, no matter at what stage - either when transmitting the lower 16 bits of the block number, or when transmitting the higher ones.
378 -\\Для выполнения этих действий следует переслать требуемую часть битов номера блока в DR и затем переслать в CSR код команды, после чего следует проверить на ошибку. Команды мгновенные, т.е. выполняются за один цикл обращения по МПИ.
378 +\\To perform these actions, you should send the required part of the block number bits to DR and then send the command code to CSR, after which you should check for an error. The commands are instantaneous, i.e. they are executed in one cycle of access via MPI.
379 379  
380 -== **013: Прочитать запись оглавления HFS** ==
380 +== 013: Read HFS TOC entry ==
381 381  
382 -Код команды 013, команда читает запись оглавления во внутреннюю область памяти и переключает на нее указатель для передачи данных через DR. Оглавление перед этим должно быть открыто. Порядок действий следующий:
382 +Command code 013, the command reads the TOC record into the internal memory area and switches the pointer to it for data transfer via DR. The TOC must be open before this.
383 +
384 +The procedure is as follows:
383 383  • Сбросить контроллер.
384 384  • Выдать в CSR команду "Прочитать запись оглавления" и дождаться ее окончания.
385 385  • Выдать в CSR команду "Прочитать из памяти контроллера"