Post by thread:[SX]: IREAD instruction

Hello, I have found a strange thing with the IREAD instruction in an SX52 chip. When the IREAD is set up to read the word at address $802 + the address of the IREAD instruction itself, it allways returns $cff. Could someone please test this and verify my results. Here is a code snippet that demonstrates this: DEVICE OSCXT2,BOR42,DRT18MS FREQ 10_000_000 RESET Startup org $0a ROM_L DS 1 ROM_H DS 1 org 0 Startup string_test mov ROM_L,#(string & $ff) mov ROM_H,#(string >> 8) loop mov w,ROM_H mov m,w mov w,ROM_L iread test w snz jmp $ ; doesn't do anything usefull with w. inc ROM_L snz inc ROM_H jmp loop org $800 string dw 'ABCDEFGHIJKLMNOPQRSTUVWXYZ',0 This is assmebled, programmed and single stepped with the SX- Key Rev E. The IREAD fails when it is reading the 'J' from the string. The IREAD instruction is at address $007 and the 'J' is at address $809. ============================== Ruben Jvnsson AB Liros Electronic Box 9124, 200 39 Malmv, Sweden TEL INT +46 40142078 FAX INT +46 40947388 spam_OUTrubenTakeThisOuTpp.sbbs.se ============================== -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads

source= http://www.piclist.com/postbot.asp?id=piclist\2002\05\27\070808a What is the date code on the SX52? Some older versions are not supported with the SX-Key Rev E. http://www.sxlist.com/techref/ubicom/sx48-52.htm Is the failure reliable? If not, it may be a communications failure between the SX-Key and the PC or excessive noise or bad connection between the key and 52. I've seen a lot of "strange" things with SX-Keys. Try a test program that counts up a register from "A" and compairs it with the data from the IREAD and turns on an LED if they don't match, then run it off the SX-Key. If it works, consider replaceing the SX-Key with rev F (latest) from Parallax Inc or switch to the SX-DEV. http://www.sxlist.com/techref/ubicom/debuggers.htm --- James Newton: PICList.com webmaster, former Admin #3 .....jamesnewtonKILLspam@spam@piclist.com 1-619-652-0593 phone http://www.piclist.com/member/JMN-EFP-786 PIC/PICList FAQ: http://www.piclist.com -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads