<\/p>\n\r\n;\r\n; doing [g] [1\/x] (15 74)\r\n; S=...3.5...9.....F\r\n;\r\n03003: if c[m] = 0 then goto 01034 ; Divide by zero\r\n03034: delayed rom 2 ;\r\n03035: if n\/c goto 0374 ;\r\n01374: if n\/c goto 0231 ;\r\n\r\nerror:\r\n01231: 0 -> a[w] ; A=00000000000000\r\n01232: 0 -> c[w] ;\r\n01233: 0 -> s 1 ;\r\n01234: 0 -> s 2 ;\r\n01235: p <- 13 ; P=13\r\n01236: load constant 14 ; C=E0000000000000 P=12\r\n01237: load constant 10 ; C=EA000000000000 P=11\r\n01240: load constant 10 ; C=EAA00000000000 P=10\r\n01241: load constant 12 ; C=EAAC0000000000 P= 9\r\n01242: load constant 10 ; C=EAACA000000000 P= 8 \"Error\"\r\n01243: binary ;\r\n01244: c - 1 -> c[wp] ; C=EAACAFFFFFFFFF\r\n01245: a exchange c[w] ; A=EAACAFFFFFFFFF C=00000000000000\r\n01246: b exchange c[w] ;\r\n01247: display off ;\r\n01250: display toggle ; \"Error \"\r\n;\r\n; for i=0x400 to -1 step -1\r\n01251: p <- 2 ; P= 2\r\n01252: load constant 4 ; C=00000000000400 P= 1\r\n01253: c - 1 -> c[x] ; C=000000000003FF\r\n01254: if n\/c goto 0253 ;\r\n01253: c - 1 -> c[x] ; C=000000000003FE\r\n01254: if n\/c goto 0253 ;\r\n...\r\n01253: c - 1 -> c[x] ; C=00000000000001\r\n01254: if n\/c goto 0253 ;\r\n01253: c - 1 -> c[x] ; C=00000000000000\r\n01254: if n\/c goto 0253 ;\r\n01253: c - 1 -> c[x] ; C=00000000000FFF\r\n01254: if n\/c goto 0253 ;\r\n; next i\r\n;\r\n01255: display toggle ; (display off) \r\n;\r\n; for i=255 to -1 step -1\r\n01256: c - 1 -> c[wp] ; C=00000000000FFE\r\n01257: if n\/c goto 0256 ;\r\n01256: c - 1 -> c[wp] ; C=00000000000FFD\r\n01257: if n\/c goto 0256 ;\r\n01256: c - 1 -> c[wp] ; C=00000000000FFC\r\n01257: if n\/c goto 0256 ;\r\n...\r\n01256: c - 1 -> c[wp] ; C=00000000000F01\r\n01257: if n\/c goto 0256 ;\r\n01256: c - 1 -> c[wp] ; C=00000000000F00\r\n01257: if n\/c goto 0256 ;\r\n01256: c - 1 -> c[wp] ; C=00000000000FFF\r\n01257: if n\/c goto 0256 ;\r\n; next i\r\n;\r\n01260: display toggle ; display on again\r\n;\r\n01261: 0 -> s 15 ; S=...3.5...9......\r\n01262: if 1 = s 15 then goto 01261 ; if key down, wait for up\r\n;\r\n01264: 0 -> s 3 ; if RUN mode\r\n01265: if 1 = s 3 then goto 01271 ;\r\n;\r\n; while RUN mode and not key press\r\n01271: if 1 = s 15 then goto 01276 ;\r\n01273: 0 -> s 3 ;\r\n01274: if 1 = s 3 then goto 01271 ;\r\n; endwhile\r\n;\r\n<\/pre>\n<\/code><\/p>\n
It displays Error for 4 time periods, blanks the display for 1 time period – to get your attention, and then sits there with Error displayed.<\/p>\n
Both loops use up 2 opcodes. Per the HP Journal article on the HP-67, there are about 3000 woodstock opcodes per second. The 0x400 loop is 1024×2 opcodes, about 2\/3 of a second. The blanked out period is a quarter of that, just 1\/6 of a second.<\/p>\n
You have to let go of the key that you pressed. Then you can press a key to clear the Error display, or switch to PRGM mode.<\/p>\n
Here’s what happens next (on pressing a key, so s 15 gets set):
\n<\/p>\n\r\n\r\n; S=...3.5...9.....F\r\n01274: if 1 = s 3 then goto 01271 ;\r\n01271: if 1 = s 15 then goto 01276 ;\r\n01276: display toggle ;\r\n01277: delayed rom 0 ;\r\n01300: if n\/c goto 0062 ;\r\n00062: 0 -> s 12 ;\r\n00063: jsb 0323 ;\r\n00323: p <- 1 ;\r\n00324: load constant 2 ; C=00000000000F2F P= 0\r\n00325: c -> addr ;\r\n00326: data register -> c 15 ; C=00000000000000\r\n00327: b exchange c[w] ;\r\n00330: return ;\r\n00064: if n\/c goto 0114 ;\r\n00114: jsb 0315 ;\r\n00315: if 1 = s 2 then goto 00321 ;\r\n00317: if 0 = s 1 then goto 00322 ;\r\n00322: return ;\r\n00115: binary ;\r\n00116: delayed rom 2 ;\r\n00117: jsb 0167 ;\r\n01167: ... ; 0 -> s 0,4,6-8,10,13,14\r\n01177: return ;\r\n00120: b -> c[w] ;\r\n00121: if 1 = s 2 then goto 00223 ;\r\n00123: 0 -> s 1 ;\r\n00124: 0 -> s 11 ;\r\n00125: 0 -> c[s] ;\r\n00126: m1 exch c ; C=0000000000006B M1=00000000000000\r\n00127: b -> c[w] ; C=00000000000000\r\n00130: 0 -> s 3 ;\r\n00131: if 0 = s 3 then goto 00232 ;\r\n00133: if 0 = s 12 then goto 00140 ;\r\n00140: delayed rom 4 ;\r\n00141: jsb 0000 ;\r\n02000: ... ; get last x\r\n02172: return ;\r\n00142: delayed rom 2 ;\r\n00143: jsb 0371 ;\r\n01371: ... ; format x in A and B\r\n01107: return ; A=0000FFFFFFFF00 B=29000000000000\r\n00144: cpu woodstock ;\r\n00145: display off ;\r\n00146: display toggle ; \"0.00\"\r\n00147: 0 -> s 15 ; S=...3.5...9......\r\n00150: if 1 = s 15 then goto 00147 ;\r\n00152: 0 -> s 1 ;\r\n00153: 0 -> s 3 ;\r\n00154: if 0 = s 3 then goto 00163 ;\r\n00156: if 0 = s 11 then goto 00165 ;\r\n00165: 0 -> s 5 ;\r\n00166: if 1 = s 5 then goto 00173 ;\r\n00173: if 0 = s 15 then goto 00152 ;\r\n00152: ...\r\n<\/pre>\n<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"
Here’s how “Error” gets displayed by the HP-29C.<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[16,5,66],"tags":[32],"_links":{"self":[{"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/posts\/1932"}],"collection":[{"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/comments?post=1932"}],"version-history":[{"count":8,"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/posts\/1932\/revisions"}],"predecessor-version":[{"id":1949,"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/posts\/1932\/revisions\/1949"}],"wp:attachment":[{"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/media?parent=1932"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/categories?post=1932"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sydneysmith.com\/wordpress\/wp-json\/wp\/v2\/tags?post=1932"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}