From: wa2ise@cbnewsb.cb.att.com (robert.f.casey) Newsgroups: rec.radio.amateur.misc Subject: ICxx71 ram adaptor for use with eprom programmer Keywords: mod Message-ID: <1991Nov3.211340.28400@cbfsb.att.com> Date: 3 Nov 91 21:13:40 GMT Sender: news@cbfsb.att.com Organization: AT&T Bell Laboratories Lines: 41 copied from packet: Msg# TSF Size #Rd Date Time From MsgID To 63934 BN 2638 0 24-Oct 0027 DG8FZ 91A211DG8FZ ICOM@WW (NONE) Sb: IC-xx71-ram-adapter (1. update) de DG8FZ @ DB0SIF how to read/programm the ICOM-battery-RAM by EPROMER: Adapter ICOM-RAM <==> 2764-Programmer socket 12.dez.89 .................... . R 5V 20.------ 28 +5V the factory programs Q4-7 16-19 -+ . A CS 19.---(*) the lower 255 Nibbels... 0V 14 ----+-- 1 E M AD 9 18.------ 24 A 9 .2 AD 8 17.------ 25 A 8 you find the frequency- +5V 28 --o..o- 3 WP U AD 7 16.------ 3 A 7 range reading the 'hexdump' Q3 15 -------.4 D3 N AD 6 15.------ 4 A 6 backwards. Q2 13 -------.5 D2 I AD 5 14.------ 5 A 5 Q1 12 -------.6 D1 T AD 4 13.------ 6 A 4 my tnx to dl8scu @ db0aaa, Q0 11 -------.7 D0 AD 3 12.------ 7 A 3 df8wu @ db0lj , Prog 27 -------.8 WR' AD 2 11.------ 8 A 2 dc4fe & testet with: . AD 1 10.------ 9 A 1 dl8zaw @ db0sif IC-751 , 271h, . upside AD 0 9.------ 10 A 0 471e,1271a. .................... CE--20-inv.-- OE--22- nand--(*) use a 4011 for the nand's and the inverter. nand-- dont forget to set the unused 4011 inputs high. PGM-27- if your eprommer cancels operation with a 'no eprom inside'-error contact each eprommer-pin to a normal 2764 but dont connect the pins 11,12,13,15,27 of the normal eprom, dont connect the pins 16-19 to 0V as shown above, program the 2764 to all bytes = low before. 73's de Karl (dg8fz @ db0sao.deu.eu) 12.Dez.89, 21.Okt.91 =========================================================================== Note: I haven't tried or verified this, proceed at your own risk. Please direct questions to DG8FZ@db0sao.deu.eu on packet. WA2ISE