GoSDC-Atom Guide

# Installation | ## ↖

## General information

1) Be aware of which GoSDC-Atom you have :

- The 'OSR' version plugs into IC20, the OS/BASIC ROM socket
- The 'PRO' version plugs into IC22, the 6502 processor socket

2) Take note of GoSDC's 6-pin configuration header (the one with the red jumper on it), in the following picture :

Its pins (in the orientation shown in the picture) are numbered :

5 | 6
3 | 4
1 | 2

So, in this example, there's a red jumper on 4+6 (note that your jumper may be a different colour). There's always a jumper on either 2+4 (selecting the secondary copy of the software) or 4+6 (selecting the primary copy of the software). The 'adapter', if installed (see below), connects to 3+5. (PRO differs)

3) Take note of the 'extra' that was supplied with your GoSDC : a 'socket-to-wire-to-jumper' adapter. (PRO differs)

## Atom installation

1) Separate the two 'halves' of your Atom by removing the relevant screws.

2) Looking at the PCB with the keyboard face down, take note of the IC sockets marked 'IC20', 'IC21', 'IC22' and 'IC24'.

3) About the 'socket-to-wire-to-jumper' adapter (henceforth called 'the adapter') that came with your GoSDC. Only with the adapter installed, GoSDC can act as the utility or extension ROM. (PRO differs)

4) Choose one of the following configuration options :

Option | GoSDC version | Adapter socket | GoSDC can act as utility or extension ROM
--- | --- | --- | ---
A | OSR | - | Neither
B | OSR | IC24 | Utility ROM
C | OSR | IC21 | Extension ROM
D | PRO | n/a | Both

### Option A

- Power down your machine.
- Remove the OS/BASIC ROM from socket IC20.
- Gently but firmly insert GoSDC into socket IC20 (refer to the picture for the correct orientation).

You should have (had) something resembling these pictures ('before' towards the left, 'after' towards the right) :

| → |  | → |

Ready.

### Option B

- Power down your machine.
- If there is a ROM in socket IC24, remove it.
- Gently but firmly insert the adapter into socket IC24 (refer to the picture for the correct orientation).
- Remove the OS/BASIC ROM from socket IC20.
- Gently but firmly insert GoSDC into socket IC20 (refer to the picture for the correct orientation).
- Push the adapter jumper on pin 3+5 of GoSDC's configuration header.

You should have (had) something resembling these pictures ('before' towards the left, 'after' towards the right) :

| → |  | → |

Ready.

### Option C

- Power down your machine.
- If there is a ROM in socket IC21, remove it.
- Gently but firmly insert the adapter into socket IC21 (refer to the picture for the correct orientation).
- Remove the OS/BASIC ROM from socket IC20.
- Gently but firmly insert GoSDC into socket IC20 (refer to the picture for the correct orientation).
- Push the adapter jumper on pin 3+5 of GoSDC's configuration header.

You should have (had) something resembling these pictures ('before' towards the left, 'after' towards the right) :

| → |  | → |

Ready.

### Option D

- Power down your machine.
- Remove the OS/BASIC ROM from socket IC20.
- Move the 6502 processor from socket IC22 to the socket on GoSDC.
- Gently but firmly insert GoSDC into socket IC22 (refer to the picture for the correct orientation).

You should have (had) something resembling these pictures ('before' towards the left, 'after' towards the right) :

| → |  | → |

Ready.

(PRO differs) The PRO version of GoSDC-Atom does not need an adapter, so it does not come with one, and there is no pin 1, 3 or 5 on its configuration header (only 2, 4 and 6).