29th January 2021

Almost February already - gee I'm getting slack with the blog updates! All the PCB's on order arrived quite a while ago - some are shown below, but also there was the assembly jig parts, and programming adapters.

We assembled a ROMXe board, and the programming adapter. This is pretty much what the production ROMXe PCB will look like :

This is the DIP programming adapter and assembly jig. The SMT carrier tape on the assembly jig is to help level the PCB's when they are placed on the jig, due to the components on the rear of the board. This helps it sit nice and level while the pins are installed. The carrier tape was just the right height :

The DIP programming adapter is used to put the initial flash image onto the board during production programming :

ROMXe only needs the one socket when programming - the EF adapter part of the board just hangs out there.

And ROMXe with initial firmware running in a IIe! :

We're still working on the firmware and finalising the CPLD code, but getting there. Jeffs working on the RTC support at present.

In other news I managed to secure a Rev 4 board to use for testing the 2513 character ROM board sets without having to pull my Apple II apart. The Rev 4 board and case was donated by David O'Sullivan - thanks David!

David had removed all IC's from the board as he was restoring another Rev 4 (which we managed to get up and running last weekend) and needed the chips for spares.

Fortunately I was able to secure a Rev 7 pre-RFI board as a chip donor. Thank you Sean McNamara for organising that board for me, and to David Wilson who generously donated the board to Sean along with a bunch of other equipment which has been distributed to various tinkerers around the country. Thank you David - its come to a good home :)

I was able to get all the chips swapped over and eventually got the board up and running with a ROMX board set installed.

Had a few hurdles along the way - mostly from poor socket contact (dirty leads on the chips). I had an issue with no clock - busted out the scope and traced the issue right back to this fellow :

The lead had rusted right through! Swapped the crystal out and after cleaning a few chip leads it was running so thanks again to everyone who helped me get this machine together :) I am still chasing a power supply for it - 240V if anyone has a spare that they would sell me.

Next we'll assemble a ROMXc board and give that a quick test using the ROMXe firmware which will be sufficient for some inital ROM switching tests. We'll also assemble a character ROM for the IIe.

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