68030 CPU Board REV7 Jumper Settings
Jumper Default Description J1 Shorted Reserved for future use J2 OPEN Reserved for future use J4 OPEN Connects 68882 FPU to oscillator US when shorted J5 SHORTED Connects 68882 FPU to oscillator U1 when shorted J6 OPEN Disables 68030 MMU when shorted J7 ---->> OPEN for 50MHz clock speed and SHORTED for lower clock speeds J9 SHORTED Remove this jumper to enable the 68030 Boot code EPROMS (U23 and U25) when these are installed J10 SHORTED A2000 Motherboard type. Shorted for A2000 motherboards REV4.0 and up (type B2000) Open for original 4-layer German motherboard. When this jumper is left open the 68000 CPU must be removed. J11 OPEN Disables 68030 CPU and bootup in 68000 mode when shorted J12 OPEN SHORT to change clocking mode for compatibility with old German A2000 motherboard J13 OPEN SHORT to change clocking mode for compatibility with old German A2000 motherboard J14 SHORTED OPEN to change clocking mode for compatibility with old German A2000 motherboard J15 SHORTED OPEN to DISABLE the code contained in the Autoboot EPROM (U34) J16 SHORTED Reserved for diagnostic use J17 SHORTED Set size of EPROM being used for "AT" Autoboot EPROM (U34) SHORTED for 27256 type and OPEN for 27128 type J18 SHORTED OPEN when an "AT" hard drive is connected to enable the "AT" driver code in the Autoboot EPROM (U34). This jumper is only relevant when using Autoboot EPROM v3 or later. NOTE: J10, J12, J13 and J14 are a set and must be changed over at the same time when installing into an A2000 with an old 4-layer German board. 68000 CPU must also be removed at the same time.32-bit Wide A2000-RAM32 Rev 3 Jumper Settings
Jumper Default Description J1 SHORTED Refresh rate J2 OPEN Refresh rate J3 ---->> Refresh rate, OPEN for 50MHz, Shorted for lower clock. J4 SHORTED Refresh rate J11 OPEN Refresh rate J8 SHORTED Refresh enable J6 SHORTED Reserved CN11 ---->> All pins OPEN for 50MHz clock speed. SHORT pins 2 and 3 for lower clock speeds. Pin 1 indicated by arrowhead. CN12 SHORT1-2 SHORT pins 1 and 2. Pein 1 indicated by arrowhead. CN13 ---->> SHORT for 50MHz clock speed OPEN for lower. J5 ---->> SHORTED when using only (up to 8) 1MB SIMMs. NOTE that this is the only option supported for speeds below 50MHz 50MHz clock speed option only: OPEN when using FOUR 1 MB SIMMs in sockets CN3-CN6 and up to FOUR 4 MB SIMMs in sockets CN7-CN10. Allows a maximum of 20MB 32-bit wide RAM.RAM Settings
RAM SIZE RAM Type Qty RAM Location Jumper J5 2 SIMM32-1MB 2 CN3-CN4 On 4 SIMM32-1MB 4 CN3-CN6 On 8 SIMM32-1MB 8 CN3-CN10 On 8* SIMM32-1MB 4 CN3-CN6 Off SIMM32-4MB 1 CN7 Off 12* SIMM32-1MB 4 CN3-CN6 Off SIMM32-4MB 2 CN7-CN8 Off 16* SIMM32-1MB 4 CN3-CN6 Off SIMM32-4MB 3 CN7-CN9 Off 20* SIMM32-1MB 4 CN3-CN6 Off SIMM32-4MB 4 CN7-CN10 Off * Note: These RAM settings require the use of the SIMM32-4MB which only fuction in the 50MHz version of the '030 accelerator. It also requires that jumper J5 be open.