That's an awesome find Don, thanks! Rich
Sent from my iPhone > On Mar 13, 2016, at 3:23 AM, Don North <no...@alum.mit.edu> wrote: > > Ok, filed as: https://github.com/simh/simh/issues/285 > >> On 3/12/2016 11:14 PM, Don North wrote: >> Fixed! >> >> sim> set cpu 11/34 256K fpp >> sim> set tdc enable >> sim> attach tdc0 tu58.dsk >> sim> b tdc0 >> >> BOOTING UP XXDP-XM EXTENDED MONITOR >> >> XXDP-XM EXTENDED MONITOR - XXDP V2.5 >> REVISION: F0 >> BOOTED FROM DD0 >> 124KW OF MEMORY >> UNIBUS SYSTEM >> >> RESTART ADDRESS: 152000 >> TYPE "H" FOR HELP ! >> >> In file pdp11_td.c, comment out/delete line 1023 (red) "ctlr->rx_buf = >> ctlr->obuf[ctlr->obptr++]; /* get first byte */" >> >> This would seem to be priming the read routine, but in fact it is discarding >> the first byte of the block zero bootstrap. >> >> Don >> >> >> case TD_OPBOO: >> if (ctlr->ibptr < 2) { /* whole packet read? >> */ >> ctlr->ilen = 2; >> ctlr->o_state = TD_GETDATA; /* get rest of packet >> */ >> return; >> } >> else { >> int8 *fbuf; >> int i; >>
