Paper tape Utilities/Images

Dave, Most of the serial PTR/PTP I used were not unlike the ASR33, The only protocal was the usual; start and stop bits of serial comms. So for every byte read by the reader you got a byte in serial form. It's just a stream of chars (7 or 8bit) as punched on the tape. Reminder, leader on most of those will be read as zeros so the average tape will have a long line of zeros preceeding the content. There was one I'd used (deep memory test ca1977) that used the CTS line on the serial output to a corospnding line on the serial input (both for punch and reader) as hardware flow control (their manual called it hardware restraint). For that case CTS gated read(send bytes) no read and for the punch case CTS gated the hosts ability to send the next byte until the punch was ready for the next character. This was only needed for slow (read case) hosts that could not accept the 300cps read or a fast (relative) host that could over run the 75cps punch. Oddly enough the unit (punch reader was Remex with custom third party board) only had 4800 baud serial rate! Only saw one like it and the closest Remex model was parallel only. That's the hardware.. The tapes them selves could be Intel hex format, Moto S records, binary, ASCI text or some vendors format (relocatable binary or hex in some cases). Never minding DEC BIN and RIM formats. The oddest and is old Intel BNPF! FYI: for those not familiar that was a ROM submission format and Xasm output format. Each byte was recorded on Ptape as example: 11000011 C3h BPPNNNNPPF (yes 10 chars on tape!) 00000000 00h BNNNNNNNNF 00010000 10h BNNNPNNNNF The small advanatage is human readable. It was self cehcking at the char level as anything other than BNPF was invalid. I was wasy to do a simple reader needed only to sense three holes (sprocket and two bits) to discern if the character was B,N,P or F making it very easy to serialize. I had to do that back in '74 as a lab EE for a controller (8008 based) project. Allison