not really specifically tested at other addresses but initially I found that my code was working or not working simply by editing the code, it was a long process to reduce the code to 2 instructions I can try at several addresses in anycase the chip is always at the same address. it's decoded by a 74LS138 + 74LS04 as the ch376 is faster than the 6502 I was thinking that the data could be removed from the bus by the ch376 before the 6502 got them... but why do I find a difference when the code doing the read is placed at odd or even addresses... the ch376 as 2 ports DATA and COMMAND/STATUS this code read the directory of usb key if the read is at odd addreses I get the right directory content if the read is at even addresses I get 00 the commands works, reading the directory involves several commands all working On 30/03/2016 10:37, A. Fachat wrote: > > > Am 30. März 2016 10:15:24 schrieb didier derny <didier@aida.org>: > >> I have a problem with a read with a 6502 >> >> I read a data on a register (from a CH376S) >> >> I have the following code: >> >> *= 2000 >> readdata LDA CH376data >> RTS >> >> >> this code always get the wrong value >> >> *= 2001 >> readdata LDA CH376data >> RTS >> >> >> now with this code I get the right value... > > That could be a broken address line to the IO chip or a timing issue > in the address decode depending on the addresses. > > André > > > > Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2016-03-30 10:00:02
Archive generated by hypermail 2.2.0.