Dave I am in the middle of bringing my board up. I have so far step by step assembly notes for everybody with tests at each step. I am bringing it up as a bus master first. Have monitor and onboard RAM working fine but for some reason all bus RAM is showing up as FF’s. Currently debugging!
There are a lot of jumpers each of which will require a detailed explanation. I’m am trying to get it debugged/ written up before others start into it so excuse the quick reply.
All the K’s have to do with master/slave switching. For a simple master, XFERI & XFERII just go to ground, K4 2-3 (slight bug, to have 68K LED active bend out pin 1 of U71 and wire wrap 1,2 & 3 together). JP13 is a carryover from the original Wilcox board and is basically now just a connection point in case one wants to hookup a external single step circuit as he had originally. Yes always closed.
See below for others
From: n8vem...@googlegroups.com [mailto:n8vem...@googlegroups.com] On Behalf Of yoda
I have some questions on the jumpers. I am not quite sure what the settings should be for K1, K2, and K4 as they are new and probably have something to do with the TMA stuff. Also it seems that JP13 must always be Closed or I don't understand the function of it.
Here is what I have come up with so far - I am going to start using as a bus master with no SMB currently in the system I have labeled some with ? Could you clarify or confirm them? Thanks
J9 Open Watch Dog Timer ------- Closed
J10 Closed Auto Vector enabled
J13 Open Enable Various Interrupts
J14 1-3, 2-4 ROM at XX8000
J15 Closed Enable Boot Feature
JB1 1-2, 3-4 Values for 28C256 eeprom
JB2 3-4, 7-8 Values for 62256 memory
JP1 Open OV_A
JP2 Open OV_B
JP3 Open OV_C
Do not add this circuit until later, it’s for DMA in slave mode will explain later.
JP4 1-2 Connect to SDSB*
JP5 Open S100 pin 65
Only if these signals are not generated by front panel or our SMB
JP6 1-2 Bus_RESET*
JP7 1-2 HOLD*
JP8 1-2 SLAVE_CLR*
JP9 1-2 POC*
JP10 1-2 BUS_RESET*
JP11 1-2 MWRT*
JP12 1-2 Clock*
JP13 1-2 ???? seems this needs to be always connected see above
Do not add this circuit until later it’s for DMA in slave mode will explain later.
JP14 Open BR* ???????
JP15 1-2 PHLDA*
JP16 Open S100 pin 66
These are fine
K1 1-3 XFERI ?????
K2 3-4 XFERII ?????
K3 1-2 NMI*
K4 2-3 XFERII
K5 2-3 DODSB*
K6 2-3 HALT
K7 2-3 bA20 ------- 1-2
P2 dependent Sets number of Wait States
The whole U2,U3 cascade is for handshaking on master to slave transition and DMA designation
In master mode this whole circuit can be ignored
P5 1-2 TMAXPU* ?????
P6 1-2, 5-6 Passes Master Reset through ???? For master P6 1-3 and 5-6 check pins carefully