Addition to my article "The effect of the OUTD command on the carry flag"

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From Ivan Roshin To All 20 April 2003

Hello, All! ═══════════════════ add.t Addition to my article "The effect of the OUTD command on the carry flag" ──────────────────────────────── ──────────────────────────────── Unfortunately, the installation algorithm outlined in this article The transfer flag turned out to be not entirely accurate. I found out about this having read [1] - the most complete, in my opinion, review undocumented features of the Z80. It says that the flag transfer when executing a command, OUTD is formed based on the result adding the number issued to the port and the value of the L register (after decrease HL). Those. if the result of addition is greater 255, the carry flag is set, otherwise it is reset. Having checked this information on a real Z80, I was convinced of its correctness. Sources ───────── 1.Sean Young. "The Undocumented Z80 Documented". This document is available at www.z80.info (full address document - http://www.z80.info/zip/z80-documented.pdf), and also on its author's website - www.msxnet.org (in the "MSX" section Technical" contains pdf and LATEX versions of the document). ════════════════════════ ════════════════════════ Best regards, Ivan Roshchin.