In SX Microcontrollers, SX/B Compiler and SX-Key Tool, John Kauffman wrote:

[3]Variable's Nibbles Copied Onto Pins[/3]

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[3]I am trying to get the Parallax LCD AppMod to work with an SX (Tech Tool). The SX/B help example uses 8 wire bus, but the AppMod is supposed to work on 4 wire bus as well. An earlier post helped with the masking technique.[/3]

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[3]I built a cable/adaptor that connects equivalent number pins from AppMod header to the SX RB pins. [/3]

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[3]In the SX/B program the character to display is held in a byte variable named Char as an ASCII value. The LCD AppMod expects to get that a byte across a 4-wire bus (RB.4-RB.7) in two reads: one read for the high nib and then a second read to get the low nib.[/3]

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[3]I see the masking <SPAN style="mso-spacerun: yes"> / swap trick to get the nibbles, but I don't see how to copy that value from the variable onto the four bus pins. It seems there should be a way to set the top four pins of RB to be equal to the masked value in Char. Is the syntax something like the lines that start with ???[/3]

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[3]Char<SPAN style="mso-tab-count: 2">                 var<SPAN style="mso-tab-count: 1">       byte[/3]

[3]??? LcdBusOut<SPAN style="mso-tab-count: 1">            var<SPAN style="mso-tab-count: 1">       RB.high[/3]

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[3]Char = %10000001<SPAN style="mso-tab-count: 1">     ' = 65 = "A"[/3]

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[3]??? LcdBusOut = Char &amp; $F0<SPAN style="mso-tab-count: 1"> ' put value of Char high nibble into bus pins[/3]

[3]PULSOUT LcdEnable, 3 <SPAN style="mso-tab-count: 1">        <SPAN style="mso-tab-count: 1">            ' Tell the AppMod to read the data bus[/3]

[3]SWAP Char<SPAN style="mso-tab-count: 3">                             <SPAN style="mso-tab-count: 1">            ' swap low &amp; high nib [/3]

[3]??? LcdBusOut = Char &amp; $F0<SPAN style="mso-tab-count: 1"> ' put value of Char low nibble into bus pins[/3]

[3]PULSOUT LcdEnable, 3 <SPAN style="mso-tab-count: 1">        <SPAN style="mso-tab-count: 1">            ' Tell the AppMod to read the data bus[/3]

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THanks.

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