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mg_notes:general:hardware_probing [2018/09/28 14:57] M.G. [How to Probe for Hardware] |
mg_notes:general:hardware_probing [2018/10/01 12:44] M.G. [How to Probe for Hardware] |
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| There's a big exception to the above paragraph: The Apple %%//%%c. Several companies produced Microsoft-compatible Z80 cards for the %%//%%c, including the popular AE Z-RAM series. These respond to appropriate writes, but also contain the machines built-in firmware in the "slot." So if the machine is a %%//%%c, it is safe to probe all slots for the Z80. | There's a big exception to the above paragraph: The Apple %%//%%c. Several companies produced Microsoft-compatible Z80 cards for the %%//%%c, including the popular AE Z-RAM series. These respond to appropriate writes, but also contain the machines built-in firmware in the "slot." So if the machine is a %%//%%c, it is safe to probe all slots for the Z80. | ||
| - | Finally, the Mockingboard and clones don't have slot firmware, instead having two or more 6522 VIAs present in the space normally used for slot firmware. For a two-VIA card, the VIAs are at $C400 and $C480 and have 16 registers each. Cards exist with more VIAs present on further $10-byte divisions. | + | Finally, the Mockingboard and clones don't have slot firmware, instead having two or more 6522 VIAs present in the space normally used for slot firmware. For a two-VIA card, the VIAs are at $Cs00 and $Cs80 and have 16 registers each. Cards exist with more VIAs present on further $10-byte divisions. |
| - | In this case, the Mockingboard is probably not going to look like a standard slot card when ID bytes are checked. Since it's I/O is in the firmware space, it won't work in a IIgs slot that isn't set to "your card," nor in slot 3 of a %%//e%% same as the Softcard. So probe for it under the same conditions of the Softcard. | + | In this case, the Mockingboard is probably not going to look like a standard slot card when ID bytes are checked. Since it's I/O is in the firmware space, it won't work in a IIgs slot that isn't set to "your card," nor in slot 3 of a %%//e%%, basically the same constraints as the Softcard. So probe for it under the same conditions of the Softcard. |
| ===== Recommendations for Slot Card Designers ===== | ===== Recommendations for Slot Card Designers ===== | ||